- tmp/tmp9aiw4xbu/{from.md → to.md} +2765 -985
tmp/tmp9aiw4xbu/{from.md → to.md}
RENAMED
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@@ -5,29 +5,41 @@
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This Clause describes components that C++programs may use to perform
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seminumerical operations.
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The following subclauses describe components for complex number types,
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random number generation, numeric ( *n*-at-a-time) arrays, generalized
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numeric algorithms, and
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summarized in Table [[tab:numerics.lib.summary]].
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**Table: Numerics library summary** <a id="tab:numerics.lib.summary">[tab:numerics.lib.summary]</a>
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| Subclause | | Header |
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| ------------------------ | ------------------------------ | ------------ |
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| [[numeric.requirements]] | Requirements | |
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| [[cfenv]] | Floating-
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| [[complex.numbers]] | Complex
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| [[rand]] | Random number generation | `<random>` |
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| [[numarray]] | Numeric arrays | `<valarray>` |
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| [[numeric.ops]] | Generalized numeric operations | `<numeric>` |
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| [[c.math]] |
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| | | `<tgmath.h>` |
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| | | `<cstdlib>` |
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## Numeric type requirements <a id="numeric.requirements">[[numeric.requirements]]</a>
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The `complex` and `valarray` components are parameterized by the type of
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information they contain and manipulate. A C++program shall instantiate
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these components only with a type `T` that satisfies the following
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- If `T` is a class, it has a public destructor;
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- If `T` is a class, it has a public assignment operator whose signature
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is either `T& T::operator=(const T&)` or `T& T::operator=(T)`
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- If `T` is a class, its assignment operator, copy and default
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constructors, and destructor shall correspond to each other in the
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following sense:
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differences in the semantics of initialization versus assignment. This
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gives an implementation considerable flexibility in how arrays are
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initialized.
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- If `T` is a class, it does not overload unary `operator&`.
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If any operation on `T` throws an exception the effects are undefined.
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In addition, many member and related functions of `valarray<T>` can be
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successfully instantiated and will exhibit well-defined behavior if and
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only if `T` satisfies additional requirements specified for each such
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member or related function.
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It is valid to instantiate `valarray<complex>`, but
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not be successfully instantiated for
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`complex` does not have any ordering
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## The floating-point environment <a id="cfenv">[[cfenv]]</a>
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### Header `<cfenv>` synopsis <a id="cfenv.syn">[[cfenv.syn]]</a>
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``` cpp
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namespace std {
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// types
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-
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-
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// functions
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int feclearexcept(int except);
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int fegetexceptflag(fexcept_t* pflag, int except);
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int feraiseexcept(int except);
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int fesetexceptflag(const fexcept_t* pflag, int except);
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int fetestexcept(int except);
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int fegetround(
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int fesetround(int mode);
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int fegetenv(fenv_t* penv);
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int feholdexcept(fenv_t* penv);
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int fesetenv(const fenv_t* penv);
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int feupdateenv(const fenv_t* penv);
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}
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```
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The header
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FE_TOWARDZERO
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FE_UPWARD
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FE_DFL_ENV
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```
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The header defines all functions, types, and macros the same as Clause
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7.6 of the C standard.
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The floating-point environment has thread storage duration (
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[[basic.stc.thread]]). The initial state for a thread’s floating-point
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environment is the state of the floating-point environment of the thread
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that constructs the corresponding `
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[[thread.thread.class]]) at the time it constructed the object.
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A separate floating-point environment shall be maintained for each
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thread. Each function accesses the environment corresponding to its
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calling thread.
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## Complex numbers <a id="complex.numbers">[[complex.numbers]]</a>
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The header `<complex>` defines a class template, and numerous functions
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for representing and manipulating complex numbers.
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`complex<long double>` are literal types ([[basic.types]]).
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If the result of a function is not mathematically defined or not in the
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range of representable values for its type, the behavior is undefined.
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If `z` is an lvalue expression of type
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- the expression `reinterpret_cast<cv T(&)[2]>(z)` shall be well-formed,
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- `reinterpret_cast<cv T(&)[2]>(z)[0]` shall designate the real part of
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`z`, and
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- `reinterpret_cast<cv T(&)[2]>(z)[1]` shall designate the imaginary
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part of `z`.
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Moreover, if `a` is an expression of type
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expression `a[i]` is well-defined for an integer expression `i`, then:
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- `reinterpret_cast<cv T*>(a)[2*i]` shall designate the real part of
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`a[i]`, and
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- `reinterpret_cast<cv T*>(a)[2*i + 1]` shall designate the imaginary
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template<class T> class complex;
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template<> class complex<float>;
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template<> class complex<double>;
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template<> class complex<long double>;
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// [complex.ops], operators
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template<class T>
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complex<T> operator+(const complex<T>&, const complex<T>&);
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template<class T> complex<T> operator+(const complex<T>&, const T&);
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template<class T> complex<T> operator+(const T&, const complex<T>&);
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@@ -212,11 +245,11 @@ namespace std {
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template<class T, class charT, class traits>
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basic_ostream<charT, traits>&
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operator<<(basic_ostream<charT, traits>&, const complex<T>&);
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// [complex.value.ops], values
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template<class T> constexpr T real(const complex<T>&);
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template<class T> constexpr T imag(const complex<T>&);
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template<class T> T abs(const complex<T>&);
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template<class T> T arg(const complex<T>&);
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template<class T> complex<T> conj(const complex<T>&);
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template<class T> complex<T> proj(const complex<T>&);
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template<class T> complex<T> polar(const T&, const T& = 0);
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// [complex.transcendentals], transcendentals
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template<class T> complex<T> acos(const complex<T>&);
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template<class T> complex<T> asin(const complex<T>&);
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template<class T> complex<T> atan(const complex<T>&);
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template<class T> complex<T> acosh(const complex<T>&);
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template<class T> complex<T> sinh (const complex<T>&);
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template<class T> complex<T> sqrt (const complex<T>&);
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template<class T> complex<T> tan (const complex<T>&);
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template<class T> complex<T> tanh (const complex<T>&);
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// [complex.literals], complex literals
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inline namespace literals {
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inline namespace complex_literals {
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constexpr complex<long double> operator""il(long double);
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constexpr complex<long double> operator""il(unsigned long long);
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constexpr complex<double> operator""i(long double);
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``` cpp
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namespace std {
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template<class T>
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class complex {
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public:
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-
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constexpr complex(const T& re = T(), const T& im = T());
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constexpr complex(const complex&);
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template<class X> constexpr complex(const complex<X>&);
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``` cpp
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namespace std {
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template<> class complex<float> {
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public:
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-
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constexpr complex(float re = 0.0f, float im = 0.0f);
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constexpr explicit complex(const complex<double>&);
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constexpr explicit complex(const complex<long double>&);
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template<class X> complex<float>& operator/=(const complex<X>&);
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};
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template<> class complex<double> {
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public:
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-
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constexpr complex(double re = 0.0, double im = 0.0);
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constexpr complex(const complex<float>&);
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constexpr explicit complex(const complex<long double>&);
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template<class X> complex<double>& operator/=(const complex<X>&);
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};
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template<> class complex<long double> {
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public:
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-
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constexpr complex(long double re = 0.0L, long double im = 0.0L);
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constexpr complex(const complex<float>&);
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constexpr complex(const complex<double>&);
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template<class T> constexpr complex(const T& re = T(), const T& im = T());
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```
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*Effects:* Constructs an object of class `complex`.
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`real() == re && imag() == im`.
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``` cpp
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constexpr T real() const;
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```
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``` cpp
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template<class T> complex<T> operator+(const complex<T>& lhs);
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```
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*Remarks:* unary operator.
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-
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*Returns:* `complex<T>(lhs)`.
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``` cpp
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template<class T>
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complex<T> operator+(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> complex<T> operator+(const complex<T>& lhs, const T& rhs);
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template<class T> complex<T> operator+(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `complex<T>(lhs) += rhs`.
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``` cpp
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template<class T> complex<T> operator-(const complex<T>& lhs);
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```
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*Remarks:* unary operator.
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-
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*Returns:* `complex<T>(-lhs.real(),-lhs.imag())`.
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``` cpp
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-
template<class T>
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complex<T> operator-(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> complex<T> operator-(const complex<T>& lhs, const T& rhs);
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template<class T> complex<T> operator-(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `complex<T>(lhs) -= rhs`.
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``` cpp
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template<class T>
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complex<T> operator*(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> complex<T> operator*(const complex<T>& lhs, const T& rhs);
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template<class T> complex<T> operator*(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `complex<T>(lhs) *= rhs`.
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``` cpp
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-
template<class T>
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complex<T> operator/(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> complex<T> operator/(const complex<T>& lhs, const T& rhs);
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template<class T> complex<T> operator/(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `complex<T>(lhs) /= rhs`.
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``` cpp
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-
template<class T>
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constexpr bool operator==(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> constexpr bool operator==(const complex<T>& lhs, const T& rhs);
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template<class T> constexpr bool operator==(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `lhs.real() == rhs.real() && lhs.imag() == rhs.imag()`.
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*Remarks:* The imaginary part is assumed to be `T()`, or 0.0, for the
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`T` arguments.
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``` cpp
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template<class T>
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constexpr bool operator!=(const complex<T>& lhs, const complex<T>& rhs);
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template<class T> constexpr bool operator!=(const complex<T>& lhs, const T& rhs);
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template<class T> constexpr bool operator!=(const T& lhs, const complex<T>& rhs);
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```
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*Returns:* `rhs.real() != lhs.real() || rhs.imag() != lhs.imag()`.
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template<class T, class charT, class traits>
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basic_istream<charT, traits>&
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operator>>(basic_istream<charT, traits>& is, complex<T>& x);
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```
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*Effects:* Extracts a complex number `x` of the form: `u`, `(u)`, or
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`(u,v)`, where `u` is the real part and `v` is the imaginary
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part ([[istream.formatted]]).
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*Requires:* The input values shall be convertible to `T`.
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-
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If bad input is encountered, calls `is.setstate(ios_base::failbit)`
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(which may throw `ios::failure` ([[iostate.flags]])).
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*Returns:* `is`.
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@@ -599,31 +626,27 @@ the same for each of the simpler extractions.
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template<class T, class charT, class traits>
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basic_ostream<charT, traits>&
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operator<<(basic_ostream<charT, traits>& o, const complex<T>& x);
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```
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*Effects:*
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were implemented as follows:
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``` cpp
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-
template<class T, class charT, class traits>
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-
basic_ostream<charT, traits>&
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operator<<(basic_ostream<charT, traits>& o, const complex<T>& x) {
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basic_ostringstream<charT, traits> s;
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s.flags(o.flags());
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s.imbue(o.getloc());
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s.precision(o.precision());
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s << '(' << x.real() << "," << x.imag() << ')';
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return o << s.str();
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-
}
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```
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*Note
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the use of comma as a field separator can be ambiguous.
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`
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explicit decimal point character; as a result, all inserted sequences
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complex numbers can be extracted unambiguously.
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### `complex` value operations <a id="complex.value.ops">[[complex.value.ops]]</a>
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``` cpp
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template<class T> constexpr T real(const complex<T>& x);
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@@ -672,10 +695,13 @@ template<class T> complex<T> proj(const complex<T>& x);
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``` cpp
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template<class T> complex<T> polar(const T& rho, const T& theta = 0);
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```
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*Returns:* The `complex` value corresponding to a complex number whose
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magnitude is `rho` and whose phase angle is `theta`.
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### `complex` transcendentals <a id="complex.transcendentals">[[complex.transcendentals]]</a>
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@@ -741,44 +767,42 @@ template<class T> complex<T> cosh(const complex<T>& x);
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``` cpp
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| 743 |
template<class T> complex<T> exp(const complex<T>& x);
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```
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| 745 |
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*Returns:* The complex base
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``` cpp
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| 749 |
template<class T> complex<T> log(const complex<T>& x);
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```
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*
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*
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| 755 |
-
of a strip mathematically unbounded along the real axis and in the
|
| 756 |
-
interval \[`-i times pi`, `i times pi`\] along the imaginary axis. When
|
| 757 |
-
`x` is a negative real number, `imag(log(x))` is pi.
|
| 758 |
|
| 759 |
``` cpp
|
| 760 |
template<class T> complex<T> log10(const complex<T>& x);
|
| 761 |
```
|
| 762 |
|
| 763 |
-
*
|
| 764 |
-
|
| 765 |
-
*Returns:* The complex common (base 10) logarithm of `x`, defined as
|
| 766 |
`log(x) / log(10)`.
|
| 767 |
|
|
|
|
|
|
|
| 768 |
``` cpp
|
| 769 |
-
template<class T>
|
| 770 |
-
complex<T> pow(const complex<T>& x, const complex<T>& y);
|
| 771 |
template<class T> complex<T> pow(const complex<T>& x, const T& y);
|
| 772 |
template<class T> complex<T> pow(const T& x, const complex<T>& y);
|
| 773 |
```
|
| 774 |
|
| 775 |
-
*
|
| 776 |
-
|
| 777 |
-
*Returns:* The complex power of base `x` raised to the `y`-th power,
|
| 778 |
defined as `exp(y * log(x))`. The value returned for `pow(0, 0)` is
|
| 779 |
-
implementation-defined.
|
|
|
|
|
|
|
| 780 |
|
| 781 |
``` cpp
|
| 782 |
template<class T> complex<T> sin(const complex<T>& x);
|
| 783 |
```
|
| 784 |
|
|
@@ -792,16 +816,16 @@ template<class T> complex<T> sinh (const complex<T>& x);
|
|
| 792 |
|
| 793 |
``` cpp
|
| 794 |
template<class T> complex<T> sqrt(const complex<T>& x);
|
| 795 |
```
|
| 796 |
|
| 797 |
-
*Remarks:* the branch cuts are along the negative real axis.
|
| 798 |
-
|
| 799 |
*Returns:* The complex square root of `x`, in the range of the right
|
| 800 |
half-plane. If the argument is a negative real number, the value
|
| 801 |
returned lies on the positive imaginary axis.
|
| 802 |
|
|
|
|
|
|
|
| 803 |
``` cpp
|
| 804 |
template<class T> complex<T> tan(const complex<T>& x);
|
| 805 |
```
|
| 806 |
|
| 807 |
*Returns:* The complex tangent of `x`.
|
|
@@ -870,29 +894,27 @@ constexpr complex<float> operator""if(long double d);
|
|
| 870 |
constexpr complex<float> operator""if(unsigned long long d);
|
| 871 |
```
|
| 872 |
|
| 873 |
*Returns:* `complex<float>{0.0f, static_cast<float>(d)}`.
|
| 874 |
|
| 875 |
-
### Header `<ccomplex>` <a id="ccmplx">[[ccmplx]]</a>
|
| 876 |
-
|
| 877 |
-
The header behaves as if it simply includes the header `<complex>`.
|
| 878 |
-
|
| 879 |
## Random number generation <a id="rand">[[rand]]</a>
|
| 880 |
|
| 881 |
This subclause defines a facility for generating (pseudo-)random
|
| 882 |
numbers.
|
| 883 |
|
| 884 |
In addition to a few utilities, four categories of entities are
|
| 885 |
-
described: *uniform random
|
| 886 |
*random number engine adaptors*, and *random number distributions*.
|
| 887 |
These categorizations are applicable to types that satisfy the
|
| 888 |
corresponding requirements, to objects instantiated from such types, and
|
| 889 |
-
to templates producing such types when instantiated.
|
| 890 |
-
|
| 891 |
-
|
| 892 |
-
|
| 893 |
-
|
|
|
|
|
|
|
| 894 |
|
| 895 |
Each of the entities specified via this subclause has an associated
|
| 896 |
arithmetic type ([[basic.fundamental]]) identified as `result_type`.
|
| 897 |
With `T` as the `result_type` thus associated with such an entity, that
|
| 898 |
entity is characterized:
|
|
@@ -914,75 +936,78 @@ Throughout this subclause [[rand]], the effect of instantiating a
|
|
| 914 |
template:
|
| 915 |
|
| 916 |
Throughout this subclause [[rand]], phrases of the form “`x` is an
|
| 917 |
iterator of a specific kind” shall be interpreted as equivalent to the
|
| 918 |
more formal requirement that “`x` is a value of a type satisfying the
|
| 919 |
-
requirements of the specified iterator type
|
| 920 |
|
| 921 |
Throughout this subclause [[rand]], any constructor that can be called
|
| 922 |
with a single argument and that satisfies a requirement specified in
|
| 923 |
this subclause shall be declared `explicit`.
|
| 924 |
|
| 925 |
#### Seed sequence requirements <a id="rand.req.seedseq">[[rand.req.seedseq]]</a>
|
| 926 |
|
| 927 |
A *seed sequence* is an object that consumes a sequence of
|
| 928 |
integer-valued data and produces a requested number of unsigned integer
|
| 929 |
-
values i, 0 ≤ i < 2³², based on the consumed data.
|
| 930 |
-
|
| 931 |
-
|
| 932 |
-
of random
|
|
|
|
|
|
|
| 933 |
|
| 934 |
A class `S` satisfies the requirements of a seed sequence if the
|
| 935 |
expressions shown in Table [[tab:SeedSequence]] are valid and have the
|
| 936 |
indicated semantics, and if `S` also satisfies all other requirements of
|
| 937 |
this section [[rand.req.seedseq]]. In that Table and throughout this
|
| 938 |
section:
|
| 939 |
|
| 940 |
-
#### Uniform random
|
| 941 |
|
| 942 |
-
A *uniform random
|
| 943 |
returning unsigned integer values such that each value in the range of
|
| 944 |
-
possible results has (ideally) equal probability of being returned.
|
| 945 |
-
degree to which `g`’s results approximate the ideal is often determined
|
| 946 |
-
statistically.
|
| 947 |
|
| 948 |
-
|
|
|
|
|
|
|
|
|
|
| 949 |
generator* if the expressions shown in Table
|
| 950 |
-
[[tab:
|
| 951 |
semantics, and if `G` also satisfies all other requirements of this
|
| 952 |
section [[rand.req.urng]]. In that Table and throughout this section:
|
| 953 |
|
| 954 |
The following relation shall hold: `G::min() < G::max()`.
|
| 955 |
|
| 956 |
#### Random number engine requirements <a id="rand.req.eng">[[rand.req.eng]]</a>
|
| 957 |
|
| 958 |
A *random number engine* (commonly shortened to *engine*) `e` of type
|
| 959 |
-
`E` is a uniform random
|
| 960 |
-
requirements (
|
| 961 |
-
|
| 962 |
|
| 963 |
At any given time, `e` has a state eᵢ for some integer i ≥ 0. Upon
|
| 964 |
construction, `e` has an initial state e₀. An engine’s state may be
|
| 965 |
established via a constructor, a `seed` function, assignment, or a
|
| 966 |
suitable `operator>>`.
|
| 967 |
|
| 968 |
`E`’s specification shall define:
|
| 969 |
|
| 970 |
-
A class `E` that satisfies the requirements of a uniform random
|
| 971 |
generator ([[rand.req.urng]]) also satisfies the requirements of a
|
| 972 |
*random number engine* if the expressions shown in Table
|
| 973 |
[[tab:RandomEngine]] are valid and have the indicated semantics, and if
|
| 974 |
`E` also satisfies all other requirements of this section
|
| 975 |
[[rand.req.eng]]. In that Table and throughout this section:
|
| 976 |
|
| 977 |
where `charT` and `traits` are constrained according to Clause
|
| 978 |
[[strings]] and Clause [[input.output]].
|
| 979 |
|
| 980 |
`E` shall meet the requirements of `CopyConstructible` (Table
|
| 981 |
-
[[copyconstructible]]) and `CopyAssignable` (Table
|
| 982 |
-
types. These operations shall each be of
|
| 983 |
-
𝑂(\mbox{size of state}).
|
| 984 |
|
| 985 |
#### Random number engine adaptor requirements <a id="rand.req.adapt">[[rand.req.adapt]]</a>
|
| 986 |
|
| 987 |
A *random number engine adaptor* (commonly shortened to *adaptor*) `a`
|
| 988 |
of type `A` is a random number engine that takes values produced by some
|
|
@@ -1014,11 +1039,11 @@ A::A(result_type s);
|
|
| 1014 |
```
|
| 1015 |
|
| 1016 |
*Effects:* The base engine is initialized with `s`.
|
| 1017 |
|
| 1018 |
``` cpp
|
| 1019 |
-
template<class Sseq>
|
| 1020 |
```
|
| 1021 |
|
| 1022 |
*Effects:* The base engine is initialized with `q`.
|
| 1023 |
|
| 1024 |
``` cpp
|
|
@@ -1066,12 +1091,12 @@ In that Table and throughout this section,
|
|
| 1066 |
|
| 1067 |
where `charT` and `traits` are constrained according to Clauses
|
| 1068 |
[[strings]] and [[input.output]].
|
| 1069 |
|
| 1070 |
`D` shall satisfy the requirements of `CopyConstructible` (Table
|
| 1071 |
-
[[copyconstructible]]) and `CopyAssignable` (Table
|
| 1072 |
-
types.
|
| 1073 |
|
| 1074 |
The sequence of numbers produced by repeated invocations of `d(g)` shall
|
| 1075 |
be independent of any invocation of `os << d` or of any `const` member
|
| 1076 |
function of `D` between any of the invocations `d(g)`.
|
| 1077 |
|
|
@@ -1085,12 +1110,13 @@ It is unspecified whether `D::param_type` is declared as a (nested)
|
|
| 1085 |
`class` or via a `typedef`. In this subclause [[rand]], declarations of
|
| 1086 |
`D::param_type` are in the form of `typedef`s for convenience of
|
| 1087 |
exposition only.
|
| 1088 |
|
| 1089 |
`P` shall satisfy the requirements of `CopyConstructible` (Table
|
| 1090 |
-
[[copyconstructible]]), `CopyAssignable` (Table
|
| 1091 |
-
and `EqualityComparable` (Table
|
|
|
|
| 1092 |
|
| 1093 |
For each of the constructors of `D` taking arguments corresponding to
|
| 1094 |
parameters of the distribution, `P` shall have a corresponding
|
| 1095 |
constructor subject to the same requirements and taking arguments
|
| 1096 |
identical in number, type, and default values. Moreover, for each of the
|
|
@@ -1099,20 +1125,19 @@ of the distribution, `P` shall have a corresponding member function with
|
|
| 1099 |
the identical name, type, and semantics.
|
| 1100 |
|
| 1101 |
`P` shall have a declaration of the form
|
| 1102 |
|
| 1103 |
``` cpp
|
| 1104 |
-
|
| 1105 |
```
|
| 1106 |
|
| 1107 |
### Header `<random>` synopsis <a id="rand.synopsis">[[rand.synopsis]]</a>
|
| 1108 |
|
| 1109 |
``` cpp
|
| 1110 |
#include <initializer_list>
|
| 1111 |
|
| 1112 |
namespace std {
|
| 1113 |
-
|
| 1114 |
// [rand.eng.lcong], class template linear_congruential_engine
|
| 1115 |
template<class UIntType, UIntType a, UIntType c, UIntType m>
|
| 1116 |
class linear_congruential_engine;
|
| 1117 |
|
| 1118 |
// [rand.eng.mers], class template mersenne_twister_engine
|
|
@@ -1137,30 +1162,31 @@ namespace std {
|
|
| 1137 |
// [rand.adapt.shuf], class template shuffle_order_engine
|
| 1138 |
template<class Engine, size_t k>
|
| 1139 |
class shuffle_order_engine;
|
| 1140 |
|
| 1141 |
// [rand.predef], engines and engine adaptors with predefined parameters
|
| 1142 |
-
|
| 1143 |
-
|
| 1144 |
-
|
| 1145 |
-
|
| 1146 |
-
|
| 1147 |
-
|
| 1148 |
-
|
| 1149 |
-
|
| 1150 |
-
|
| 1151 |
-
|
|
|
|
| 1152 |
|
| 1153 |
// [rand.device], class random_device
|
| 1154 |
class random_device;
|
| 1155 |
|
| 1156 |
// [rand.util.seedseq], class seed_seq
|
| 1157 |
class seed_seq;
|
| 1158 |
|
| 1159 |
// [rand.util.canonical], function template generate_canonical
|
| 1160 |
-
|
| 1161 |
-
|
| 1162 |
|
| 1163 |
// [rand.dist.uni.int], class template uniform_int_distribution
|
| 1164 |
template<class IntType = int>
|
| 1165 |
class uniform_int_distribution;
|
| 1166 |
|
|
@@ -1236,12 +1262,11 @@ namespace std {
|
|
| 1236 |
class piecewise_constant_distribution;
|
| 1237 |
|
| 1238 |
// [rand.dist.samp.plinear], class template piecewise_linear_distribution
|
| 1239 |
template<class RealType = double>
|
| 1240 |
class piecewise_linear_distribution;
|
| 1241 |
-
|
| 1242 |
-
} // namespace std
|
| 1243 |
```
|
| 1244 |
|
| 1245 |
### Random number engine class templates <a id="rand.eng">[[rand.eng]]</a>
|
| 1246 |
|
| 1247 |
Each type instantiated from a class template specified in this section
|
|
@@ -1252,25 +1277,30 @@ Except where specified otherwise, the complexity of each function
|
|
| 1252 |
specified in this section [[rand.eng]] is constant.
|
| 1253 |
|
| 1254 |
Except where specified otherwise, no function described in this section
|
| 1255 |
[[rand.eng]] throws an exception.
|
| 1256 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1257 |
Descriptions are provided in this section [[rand.eng]] only for engine
|
| 1258 |
-
operations that are not described in [[rand.req.eng]] or for
|
| 1259 |
-
|
| 1260 |
-
|
| 1261 |
-
|
| 1262 |
-
|
| 1263 |
|
| 1264 |
Each template specified in this section [[rand.eng]] requires one or
|
| 1265 |
more relationships, involving the value(s) of its non-type template
|
| 1266 |
parameter(s), to hold. A program instantiating any of these templates is
|
| 1267 |
ill-formed if any such required relationship fails to hold.
|
| 1268 |
|
| 1269 |
For every random number engine and for every random number engine
|
| 1270 |
-
adaptor `X` defined in this
|
| 1271 |
-
|
| 1272 |
|
| 1273 |
- if the constructor
|
| 1274 |
``` cpp
|
| 1275 |
template <class Sseq> explicit X(Sseq& q);
|
| 1276 |
```
|
|
@@ -1299,15 +1329,14 @@ algorithm is a modular linear function of the form
|
|
| 1299 |
TA(xᵢ) = (a ⋅ xᵢ + c) mod m; the generation algorithm is
|
| 1300 |
GA(xᵢ) = xᵢ₊₁.
|
| 1301 |
|
| 1302 |
``` cpp
|
| 1303 |
template<class UIntType, UIntType a, UIntType c, UIntType m>
|
| 1304 |
-
|
| 1305 |
-
{
|
| 1306 |
public:
|
| 1307 |
// types
|
| 1308 |
-
|
| 1309 |
|
| 1310 |
// engine characteristics
|
| 1311 |
static constexpr result_type multiplier = a;
|
| 1312 |
static constexpr result_type increment = c;
|
| 1313 |
static constexpr result_type modulus = m;
|
|
@@ -1327,11 +1356,14 @@ public:
|
|
| 1327 |
};
|
| 1328 |
```
|
| 1329 |
|
| 1330 |
If the template parameter `m` is 0, the modulus m used throughout this
|
| 1331 |
section [[rand.eng.lcong]] is `numeric_limits<result_type>::max()` plus
|
| 1332 |
-
1.
|
|
|
|
|
|
|
|
|
|
| 1333 |
|
| 1334 |
If the template parameter `m` is not 0, the following relations shall
|
| 1335 |
hold: `a < m` and `c < m`.
|
| 1336 |
|
| 1337 |
The textual representation consists of the value of xᵢ.
|
|
@@ -1366,11 +1398,11 @@ sequence X of n values of the type delivered by `x`; all subscripts
|
|
| 1366 |
applied to X are to be taken modulo n.
|
| 1367 |
|
| 1368 |
The transition algorithm employs a twisted generalized feedback shift
|
| 1369 |
register defined by shift values n and m, a twist value r, and a
|
| 1370 |
conditional xor-mask a. To improve the uniformity of the result, the
|
| 1371 |
-
bits of the raw shift register are additionally *tempered* (
|
| 1372 |
scrambled) according to a bit-scrambling matrix defined by values
|
| 1373 |
u, d, s, b, t, c, and ℓ.
|
| 1374 |
|
| 1375 |
The state transition is performed as follows:
|
| 1376 |
|
|
@@ -1383,15 +1415,14 @@ z₁, z₂, z₃, z₄ as follows, then delivers z₄ as its result:
|
|
| 1383 |
``` cpp
|
| 1384 |
template<class UIntType, size_t w, size_t n, size_t m, size_t r,
|
| 1385 |
UIntType a, size_t u, UIntType d, size_t s,
|
| 1386 |
UIntType b, size_t t,
|
| 1387 |
UIntType c, size_t l, UIntType f>
|
| 1388 |
-
|
| 1389 |
-
{
|
| 1390 |
public:
|
| 1391 |
// types
|
| 1392 |
-
|
| 1393 |
|
| 1394 |
// engine characteristics
|
| 1395 |
static constexpr size_t word_size = w;
|
| 1396 |
static constexpr size_t state_size = n;
|
| 1397 |
static constexpr size_t shift_size = m;
|
|
@@ -1468,24 +1499,23 @@ all subscripts applied to X are to be taken modulo r. The state xᵢ
|
|
| 1468 |
additionally consists of an integer c (known as the *carry*) whose value
|
| 1469 |
is either 0 or 1.
|
| 1470 |
|
| 1471 |
The state transition is performed as follows:
|
| 1472 |
|
| 1473 |
-
This algorithm corresponds to a modular linear function of
|
| 1474 |
-
TA(xᵢ) = (a ⋅ xᵢ) mod b, where b is of the form mʳ - mˢ + 1
|
| 1475 |
-
a = b - (b-1) / m.
|
| 1476 |
|
| 1477 |
The generation algorithm is given by GA(xᵢ) = y, where y is the value
|
| 1478 |
produced as a result of advancing the engine’s state as described above.
|
| 1479 |
|
| 1480 |
``` cpp
|
| 1481 |
template<class UIntType, size_t w, size_t s, size_t r>
|
| 1482 |
-
|
| 1483 |
-
{
|
| 1484 |
public:
|
| 1485 |
// types
|
| 1486 |
-
|
| 1487 |
|
| 1488 |
// engine characteristics
|
| 1489 |
static constexpr size_t word_size = w;
|
| 1490 |
static constexpr size_t short_lag = s;
|
| 1491 |
static constexpr size_t long_lag = r;
|
|
@@ -1547,19 +1577,24 @@ X₋₁ is then 0, sets c to 1; otherwise sets c to 0.
|
|
| 1547 |
### Random number engine adaptor class templates <a id="rand.adapt">[[rand.adapt]]</a>
|
| 1548 |
|
| 1549 |
#### In general <a id="rand.adapt.general">[[rand.adapt.general]]</a>
|
| 1550 |
|
| 1551 |
Each type instantiated from a class template specified in this section
|
| 1552 |
-
[[rand.
|
| 1553 |
adaptor ([[rand.req.adapt]]) type.
|
| 1554 |
|
| 1555 |
Except where specified otherwise, the complexity of each function
|
| 1556 |
specified in this section [[rand.adapt]] is constant.
|
| 1557 |
|
| 1558 |
Except where specified otherwise, no function described in this section
|
| 1559 |
[[rand.adapt]] throws an exception.
|
| 1560 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1561 |
Descriptions are provided in this section [[rand.adapt]] only for
|
| 1562 |
adaptor operations that are not described in section [[rand.req.adapt]]
|
| 1563 |
or for operations where there is additional semantic information. In
|
| 1564 |
particular, declarations for copy constructors, for copy assignment
|
| 1565 |
operators, for streaming operators, and for equality and inequality
|
|
@@ -1587,15 +1622,14 @@ state eⱼ to eⱼ₊₁.
|
|
| 1587 |
The generation algorithm yields the value returned by the last
|
| 1588 |
invocation of `e()` while advancing `e`’s state as described above.
|
| 1589 |
|
| 1590 |
``` cpp
|
| 1591 |
template<class Engine, size_t p, size_t r>
|
| 1592 |
-
|
| 1593 |
-
{
|
| 1594 |
public:
|
| 1595 |
// types
|
| 1596 |
-
|
| 1597 |
|
| 1598 |
// engine characteristics
|
| 1599 |
static constexpr size_t block_size = p;
|
| 1600 |
static constexpr size_t used_block = r;
|
| 1601 |
static constexpr result_type min() { return Engine::min(); }
|
|
@@ -1642,11 +1676,12 @@ state eᵢ of its base engine `e`; the size of the state is the size of
|
|
| 1642 |
e’s state.
|
| 1643 |
|
| 1644 |
The transition and generation algorithms are described in terms of the
|
| 1645 |
following integral constants:
|
| 1646 |
|
| 1647 |
-
The relation w = n₀ w₀ + (n - n₀)(w₀ + 1) always
|
|
|
|
| 1648 |
|
| 1649 |
The transition algorithm is carried out by invoking `e()` as often as
|
| 1650 |
needed to obtain n₀ values less than y₀ + `e.min()` and n - n₀ values
|
| 1651 |
less than y₁ + `e.min()` .
|
| 1652 |
|
|
@@ -1666,15 +1701,14 @@ for (k = n₀; k \neq n; k += 1) {
|
|
| 1666 |
}
|
| 1667 |
```
|
| 1668 |
|
| 1669 |
``` cpp
|
| 1670 |
template<class Engine, size_t w, class UIntType>
|
| 1671 |
-
class independent_bits_engine
|
| 1672 |
-
{
|
| 1673 |
public:
|
| 1674 |
// types
|
| 1675 |
-
|
| 1676 |
|
| 1677 |
// engine characteristics
|
| 1678 |
static constexpr result_type min() { return 0; }
|
| 1679 |
static constexpr result_type max() { return 2^w - 1; }
|
| 1680 |
|
|
@@ -1722,15 +1756,14 @@ transition is performed as follows:
|
|
| 1722 |
The generation algorithm yields the last value of `Y` produced while
|
| 1723 |
advancing `e`’s state as described above.
|
| 1724 |
|
| 1725 |
``` cpp
|
| 1726 |
template<class Engine, size_t k>
|
| 1727 |
-
|
| 1728 |
-
{
|
| 1729 |
public:
|
| 1730 |
// types
|
| 1731 |
-
|
| 1732 |
|
| 1733 |
// engine characteristics
|
| 1734 |
static constexpr size_t table_size = k;
|
| 1735 |
static constexpr result_type min() { return Engine::min(); }
|
| 1736 |
static constexpr result_type max() { return Engine::max(); }
|
|
@@ -1752,12 +1785,12 @@ public:
|
|
| 1752 |
// property functions
|
| 1753 |
const Engine& base() const noexcept { return e; };
|
| 1754 |
|
| 1755 |
private:
|
| 1756 |
Engine e; // exposition only
|
| 1757 |
-
result_type Y; // exposition only
|
| 1758 |
result_type V[k]; // exposition only
|
|
|
|
| 1759 |
};
|
| 1760 |
```
|
| 1761 |
|
| 1762 |
The following relation shall hold: `0 < k`.
|
| 1763 |
|
|
@@ -1770,124 +1803,121 @@ each constructor that is not a copy constructor initializes
|
|
| 1770 |
successive invocations of `e()`.
|
| 1771 |
|
| 1772 |
### Engines and engine adaptors with predefined parameters <a id="rand.predef">[[rand.predef]]</a>
|
| 1773 |
|
| 1774 |
``` cpp
|
| 1775 |
-
|
| 1776 |
-
|
| 1777 |
```
|
| 1778 |
|
| 1779 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1780 |
default-constructed object of type `minstd_rand0` shall produce the
|
| 1781 |
value 1043618065.
|
| 1782 |
|
| 1783 |
``` cpp
|
| 1784 |
-
|
| 1785 |
-
|
| 1786 |
```
|
| 1787 |
|
| 1788 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1789 |
default-constructed object of type `minstd_rand` shall produce the value
|
| 1790 |
399268537.
|
| 1791 |
|
| 1792 |
``` cpp
|
| 1793 |
-
|
| 1794 |
-
|
| 1795 |
-
|
| 1796 |
```
|
| 1797 |
|
| 1798 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1799 |
default-constructed object of type `mt19937` shall produce the value
|
| 1800 |
4123659995.
|
| 1801 |
|
| 1802 |
``` cpp
|
| 1803 |
-
|
|
|
|
| 1804 |
64,312,156,31,0xb5026f5aa96619e9,29,
|
| 1805 |
0x5555555555555555,17,
|
| 1806 |
0x71d67fffeda60000,37,
|
| 1807 |
0xfff7eee000000000,43,
|
| 1808 |
-
6364136223846793005>
|
| 1809 |
-
mt19937_64;
|
| 1810 |
```
|
| 1811 |
|
| 1812 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1813 |
default-constructed object of type `mt19937_64` shall produce the value
|
| 1814 |
9981545732273789042.
|
| 1815 |
|
| 1816 |
``` cpp
|
| 1817 |
-
|
| 1818 |
-
|
| 1819 |
```
|
| 1820 |
|
| 1821 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1822 |
default-constructed object of type `ranlux24_base` shall produce the
|
| 1823 |
value 7937952.
|
| 1824 |
|
| 1825 |
``` cpp
|
| 1826 |
-
|
| 1827 |
-
|
| 1828 |
```
|
| 1829 |
|
| 1830 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1831 |
default-constructed object of type `ranlux48_base` shall produce the
|
| 1832 |
value 61839128582725.
|
| 1833 |
|
| 1834 |
``` cpp
|
| 1835 |
-
|
| 1836 |
-
ranlux24;
|
| 1837 |
```
|
| 1838 |
|
| 1839 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1840 |
default-constructed object of type `ranlux24` shall produce the value
|
| 1841 |
9901578.
|
| 1842 |
|
| 1843 |
``` cpp
|
| 1844 |
-
|
| 1845 |
-
ranlux48;
|
| 1846 |
```
|
| 1847 |
|
| 1848 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1849 |
default-constructed object of type `ranlux48` shall produce the value
|
| 1850 |
249142670248501.
|
| 1851 |
|
| 1852 |
``` cpp
|
| 1853 |
-
|
| 1854 |
-
knuth_b;
|
| 1855 |
```
|
| 1856 |
|
| 1857 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1858 |
default-constructed object of type `knuth_b` shall produce the value
|
| 1859 |
1112339016.
|
| 1860 |
|
| 1861 |
``` cpp
|
| 1862 |
-
|
| 1863 |
-
default_random_engine;
|
| 1864 |
```
|
| 1865 |
|
| 1866 |
-
The choice of engine type named by this `typedef` is
|
| 1867 |
-
implementation-defined.
|
| 1868 |
-
|
| 1869 |
-
|
| 1870 |
-
|
| 1871 |
-
|
| 1872 |
-
|
| 1873 |
-
|
|
|
|
|
|
|
| 1874 |
|
| 1875 |
### Class `random_device` <a id="rand.device">[[rand.device]]</a>
|
| 1876 |
|
| 1877 |
-
A `random_device` uniform random
|
| 1878 |
-
|
| 1879 |
|
| 1880 |
-
If implementation limitations prevent generating
|
| 1881 |
-
|
| 1882 |
|
| 1883 |
``` cpp
|
| 1884 |
-
class random_device
|
| 1885 |
-
{
|
| 1886 |
public:
|
| 1887 |
// types
|
| 1888 |
-
|
| 1889 |
|
| 1890 |
// generator characteristics
|
| 1891 |
static constexpr result_type min() { return numeric_limits<result_type>::min(); }
|
| 1892 |
static constexpr result_type max() { return numeric_limits<result_type>::max(); }
|
| 1893 |
|
|
@@ -1908,15 +1938,15 @@ public:
|
|
| 1908 |
|
| 1909 |
``` cpp
|
| 1910 |
explicit random_device(const string& token = implementation-defined);
|
| 1911 |
```
|
| 1912 |
|
| 1913 |
-
*Effects:* Constructs a `random_device`
|
| 1914 |
-
|
| 1915 |
-
parameter are implementation-defined.[^3]
|
| 1916 |
|
| 1917 |
-
*Throws:* A value of an implementation-defined type derived from
|
| 1918 |
`exception` if the `random_device` could not be initialized.
|
| 1919 |
|
| 1920 |
``` cpp
|
| 1921 |
double entropy() const noexcept;
|
| 1922 |
```
|
|
@@ -1927,27 +1957,26 @@ returned by `operator()`, in the range `min()` to log₂( `max()`+1).
|
|
| 1927 |
|
| 1928 |
``` cpp
|
| 1929 |
result_type operator()();
|
| 1930 |
```
|
| 1931 |
|
| 1932 |
-
*Returns:* A
|
| 1933 |
-
between `min()` and `max()`, inclusive. It is implementation-defined
|
| 1934 |
-
these values are generated.
|
| 1935 |
|
| 1936 |
-
*Throws:* A value of an implementation-defined type derived from
|
| 1937 |
`exception` if a random number could not be obtained.
|
| 1938 |
|
| 1939 |
### Utilities <a id="rand.util">[[rand.util]]</a>
|
| 1940 |
|
| 1941 |
#### Class `seed_seq` <a id="rand.util.seedseq">[[rand.util.seedseq]]</a>
|
| 1942 |
|
| 1943 |
``` cpp
|
| 1944 |
-
class seed_seq
|
| 1945 |
-
{
|
| 1946 |
public:
|
| 1947 |
// types
|
| 1948 |
-
|
| 1949 |
|
| 1950 |
// constructors
|
| 1951 |
seed_seq();
|
| 1952 |
template<class T>
|
| 1953 |
seed_seq(initializer_list<T> il);
|
|
@@ -1957,11 +1986,11 @@ public:
|
|
| 1957 |
// generating functions
|
| 1958 |
template<class RandomAccessIterator>
|
| 1959 |
void generate(RandomAccessIterator begin, RandomAccessIterator end);
|
| 1960 |
|
| 1961 |
// property functions
|
| 1962 |
-
|
| 1963 |
template<class OutputIterator>
|
| 1964 |
void param(OutputIterator dest) const;
|
| 1965 |
|
| 1966 |
// no copy functions
|
| 1967 |
seed_seq(const seed_seq& ) = delete;
|
|
@@ -2011,12 +2040,11 @@ for( InputIterator s = begin; s != end; ++s)
|
|
| 2011 |
template<class RandomAccessIterator>
|
| 2012 |
void generate(RandomAccessIterator begin, RandomAccessIterator end);
|
| 2013 |
```
|
| 2014 |
|
| 2015 |
*Requires:* `RandomAccessIterator` shall meet the requirements of a
|
| 2016 |
-
mutable random access iterator
|
| 2017 |
-
(Table [[tab:iterator.random.access.requirements]]) type. Moreover,
|
| 2018 |
`iterator_traits<RandomAccessIterator>::value_type` shall denote an
|
| 2019 |
unsigned integer type capable of accommodating 32-bit quantities.
|
| 2020 |
|
| 2021 |
*Effects:* Does nothing if `begin == end`. Otherwise, with
|
| 2022 |
s = `v.size()` and n = `end` - `begin`, fills the supplied range
|
|
@@ -2027,29 +2055,26 @@ $x \, \xor \, (x \, \rightshift \, 27)$:
|
|
| 2027 |
|
| 2028 |
*Throws:* What and when `RandomAccessIterator` operations of `begin` and
|
| 2029 |
`end` throw.
|
| 2030 |
|
| 2031 |
``` cpp
|
| 2032 |
-
size_t size() const;
|
| 2033 |
```
|
| 2034 |
|
| 2035 |
*Returns:* The number of 32-bit units that would be returned by a call
|
| 2036 |
to `param()`.
|
| 2037 |
|
| 2038 |
-
*Throws:* Nothing.
|
| 2039 |
-
|
| 2040 |
*Complexity:* Constant time.
|
| 2041 |
|
| 2042 |
``` cpp
|
| 2043 |
template<class OutputIterator>
|
| 2044 |
void param(OutputIterator dest) const;
|
| 2045 |
```
|
| 2046 |
|
| 2047 |
*Requires:* `OutputIterator` shall satisfy the requirements of an output
|
| 2048 |
-
iterator
|
| 2049 |
-
|
| 2050 |
-
`result_type`.
|
| 2051 |
|
| 2052 |
*Effects:* Copies the sequence of prepared 32-bit units to the given
|
| 2053 |
destination, as if by executing the following statement:
|
| 2054 |
|
| 2055 |
``` cpp
|
|
@@ -2060,22 +2085,23 @@ copy(v.begin(), v.end(), dest);
|
|
| 2060 |
|
| 2061 |
#### Function template `generate_canonical` <a id="rand.util.canonical">[[rand.util.canonical]]</a>
|
| 2062 |
|
| 2063 |
Each function instantiated from the template described in this section
|
| 2064 |
[[rand.util.canonical]] maps the result of one or more invocations of a
|
| 2065 |
-
supplied uniform random
|
| 2066 |
-
|
| 2067 |
-
|
| 2068 |
-
|
| 2069 |
|
| 2070 |
-
Obtaining a value in this way can be a useful step in the
|
| 2071 |
-
transforming a value generated by a uniform random
|
| 2072 |
-
a value that can be delivered by a random number
|
|
|
|
| 2073 |
|
| 2074 |
``` cpp
|
| 2075 |
-
template<class RealType, size_t bits, class
|
| 2076 |
-
RealType generate_canonical(
|
| 2077 |
```
|
| 2078 |
|
| 2079 |
*Complexity:* Exactly k = max(1, ⌈ b / log₂ R ⌉) invocations of `g`,
|
| 2080 |
where b[^5] is the lesser of `numeric_limits<RealType>::digits` and
|
| 2081 |
`bits`, and R is the value of `g.max()` - `g.min()` + 1.
|
|
@@ -2103,11 +2129,11 @@ for operations where there is additional semantic information. In
|
|
| 2103 |
particular, declarations for copy constructors, for copy assignment
|
| 2104 |
operators, for streaming operators, and for equality and inequality
|
| 2105 |
operators are not shown in the synopses.
|
| 2106 |
|
| 2107 |
The algorithms for producing each of the specified distributions are
|
| 2108 |
-
implementation-defined.
|
| 2109 |
|
| 2110 |
The value of each probability density function p(z) and of each discrete
|
| 2111 |
probability function P(zᵢ) specified in this section is 0 everywhere
|
| 2112 |
outside its stated domain.
|
| 2113 |
|
|
@@ -2121,27 +2147,26 @@ probability function $$%
|
|
| 2121 |
P(i\,|\,a,b) = 1 / (b - a + 1)
|
| 2122 |
\; \mbox{.}$$
|
| 2123 |
|
| 2124 |
``` cpp
|
| 2125 |
template<class IntType = int>
|
| 2126 |
-
|
| 2127 |
-
{
|
| 2128 |
public:
|
| 2129 |
// types
|
| 2130 |
-
|
| 2131 |
-
|
| 2132 |
|
| 2133 |
// constructors and reset functions
|
| 2134 |
explicit uniform_int_distribution(IntType a = 0, IntType b = numeric_limits<IntType>::max());
|
| 2135 |
explicit uniform_int_distribution(const param_type& parm);
|
| 2136 |
void reset();
|
| 2137 |
|
| 2138 |
// generating functions
|
| 2139 |
-
|
| 2140 |
-
|
| 2141 |
-
|
| 2142 |
-
|
| 2143 |
|
| 2144 |
// property functions
|
| 2145 |
result_type a() const;
|
| 2146 |
result_type b() const;
|
| 2147 |
param_type param() const;
|
|
@@ -2180,29 +2205,31 @@ A `uniform_real_distribution` random number distribution produces random
|
|
| 2180 |
numbers x, a ≤ x < b, distributed according to the constant probability
|
| 2181 |
density function $$%
|
| 2182 |
p(x\,|\,a,b) = 1 / (b - a)
|
| 2183 |
\; \mbox{.}$$
|
| 2184 |
|
|
|
|
|
|
|
|
|
|
| 2185 |
``` cpp
|
| 2186 |
template<class RealType = double>
|
| 2187 |
-
|
| 2188 |
-
{
|
| 2189 |
public:
|
| 2190 |
// types
|
| 2191 |
-
|
| 2192 |
-
|
| 2193 |
|
| 2194 |
// constructors and reset functions
|
| 2195 |
explicit uniform_real_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 2196 |
explicit uniform_real_distribution(const param_type& parm);
|
| 2197 |
void reset();
|
| 2198 |
|
| 2199 |
// generating functions
|
| 2200 |
-
|
| 2201 |
-
|
| 2202 |
-
|
| 2203 |
-
|
| 2204 |
|
| 2205 |
// property functions
|
| 2206 |
result_type a() const;
|
| 2207 |
result_type b() const;
|
| 2208 |
param_type param() const;
|
|
@@ -2247,27 +2274,26 @@ values b distributed according to the discrete probability function $$%
|
|
| 2247 |
1-p & \mbox{if} & b = \tcode{false}
|
| 2248 |
\end{array}\right.
|
| 2249 |
\; \mbox{.}$$
|
| 2250 |
|
| 2251 |
``` cpp
|
| 2252 |
-
class bernoulli_distribution
|
| 2253 |
-
{
|
| 2254 |
public:
|
| 2255 |
// types
|
| 2256 |
-
|
| 2257 |
-
|
| 2258 |
|
| 2259 |
// constructors and reset functions
|
| 2260 |
explicit bernoulli_distribution(double p = 0.5);
|
| 2261 |
explicit bernoulli_distribution(const param_type& parm);
|
| 2262 |
void reset();
|
| 2263 |
|
| 2264 |
// generating functions
|
| 2265 |
-
|
| 2266 |
-
|
| 2267 |
-
|
| 2268 |
-
|
| 2269 |
|
| 2270 |
// property functions
|
| 2271 |
double p() const;
|
| 2272 |
param_type param() const;
|
| 2273 |
void param(const param_type& parm);
|
|
@@ -2301,27 +2327,26 @@ $$%
|
|
| 2301 |
= \binom{t}{i} \cdot p^i \cdot (1-p)^{t-i}
|
| 2302 |
\; \mbox{.}$$
|
| 2303 |
|
| 2304 |
``` cpp
|
| 2305 |
template<class IntType = int>
|
| 2306 |
-
|
| 2307 |
-
{
|
| 2308 |
public:
|
| 2309 |
// types
|
| 2310 |
-
|
| 2311 |
-
|
| 2312 |
|
| 2313 |
// constructors and reset functions
|
| 2314 |
explicit binomial_distribution(IntType t = 1, double p = 0.5);
|
| 2315 |
explicit binomial_distribution(const param_type& parm);
|
| 2316 |
void reset();
|
| 2317 |
|
| 2318 |
// generating functions
|
| 2319 |
-
|
| 2320 |
-
|
| 2321 |
-
|
| 2322 |
-
|
| 2323 |
|
| 2324 |
// property functions
|
| 2325 |
IntType t() const;
|
| 2326 |
double p() const;
|
| 2327 |
param_type param() const;
|
|
@@ -2363,27 +2388,26 @@ $$%
|
|
| 2363 |
= p \cdot (1-p)^{i}
|
| 2364 |
\; \mbox{.}$$
|
| 2365 |
|
| 2366 |
``` cpp
|
| 2367 |
template<class IntType = int>
|
| 2368 |
-
|
| 2369 |
-
{
|
| 2370 |
public:
|
| 2371 |
// types
|
| 2372 |
-
|
| 2373 |
-
|
| 2374 |
|
| 2375 |
// constructors and reset functions
|
| 2376 |
explicit geometric_distribution(double p = 0.5);
|
| 2377 |
explicit geometric_distribution(const param_type& parm);
|
| 2378 |
void reset();
|
| 2379 |
|
| 2380 |
// generating functions
|
| 2381 |
-
|
| 2382 |
-
|
| 2383 |
-
|
| 2384 |
-
|
| 2385 |
|
| 2386 |
// property functions
|
| 2387 |
double p() const;
|
| 2388 |
param_type param() const;
|
| 2389 |
void param(const param_type& parm);
|
|
@@ -2415,29 +2439,31 @@ random integers i ≥ 0 distributed according to the discrete probability
|
|
| 2415 |
function $$%
|
| 2416 |
P(i\,|\,k,p)
|
| 2417 |
= \binom{k+i-1}{i} \cdot p^k \cdot (1-p)^i
|
| 2418 |
\; \mbox{.}$$
|
| 2419 |
|
|
|
|
|
|
|
|
|
|
| 2420 |
``` cpp
|
| 2421 |
template<class IntType = int>
|
| 2422 |
-
|
| 2423 |
-
{
|
| 2424 |
public:
|
| 2425 |
// types
|
| 2426 |
-
|
| 2427 |
-
|
| 2428 |
|
| 2429 |
// constructor and reset functions
|
| 2430 |
explicit negative_binomial_distribution(IntType k = 1, double p = 0.5);
|
| 2431 |
explicit negative_binomial_distribution(const param_type& parm);
|
| 2432 |
void reset();
|
| 2433 |
|
| 2434 |
// generating functions
|
| 2435 |
-
|
| 2436 |
-
|
| 2437 |
-
|
| 2438 |
-
|
| 2439 |
|
| 2440 |
// property functions
|
| 2441 |
IntType k() const;
|
| 2442 |
double p() const;
|
| 2443 |
param_type param() const;
|
|
@@ -2487,23 +2513,23 @@ distribution’s *mean* .
|
|
| 2487 |
template<class IntType = int>
|
| 2488 |
class poisson_distribution
|
| 2489 |
{
|
| 2490 |
public:
|
| 2491 |
// types
|
| 2492 |
-
|
| 2493 |
-
|
| 2494 |
|
| 2495 |
// constructors and reset functions
|
| 2496 |
explicit poisson_distribution(double mean = 1.0);
|
| 2497 |
explicit poisson_distribution(const param_type& parm);
|
| 2498 |
void reset();
|
| 2499 |
|
| 2500 |
// generating functions
|
| 2501 |
-
|
| 2502 |
-
|
| 2503 |
-
|
| 2504 |
-
|
| 2505 |
|
| 2506 |
// property functions
|
| 2507 |
double mean() const;
|
| 2508 |
param_type param() const;
|
| 2509 |
void param(const param_type& parm);
|
|
@@ -2537,27 +2563,26 @@ $$%
|
|
| 2537 |
= \lambda e^{-\lambda x}
|
| 2538 |
\; \mbox{.}$$
|
| 2539 |
|
| 2540 |
``` cpp
|
| 2541 |
template<class RealType = double>
|
| 2542 |
-
|
| 2543 |
-
{
|
| 2544 |
public:
|
| 2545 |
// types
|
| 2546 |
-
|
| 2547 |
-
|
| 2548 |
|
| 2549 |
// constructors and reset functions
|
| 2550 |
explicit exponential_distribution(RealType lambda = 1.0);
|
| 2551 |
explicit exponential_distribution(const param_type& parm);
|
| 2552 |
void reset();
|
| 2553 |
|
| 2554 |
// generating functions
|
| 2555 |
-
|
| 2556 |
-
|
| 2557 |
-
|
| 2558 |
-
|
| 2559 |
|
| 2560 |
// property functions
|
| 2561 |
RealType lambda() const;
|
| 2562 |
param_type param() const;
|
| 2563 |
void param(const param_type& parm);
|
|
@@ -2570,11 +2595,11 @@ public:
|
|
| 2570 |
explicit exponential_distribution(RealType lambda = 1.0);
|
| 2571 |
```
|
| 2572 |
|
| 2573 |
*Requires:* 0 < `lambda`.
|
| 2574 |
|
| 2575 |
-
*Effects:* Constructs
|
| 2576 |
corresponds to the parameter of the distribution.
|
| 2577 |
|
| 2578 |
``` cpp
|
| 2579 |
RealType lambda() const;
|
| 2580 |
```
|
|
@@ -2592,27 +2617,26 @@ $$%
|
|
| 2592 |
\, \cdot \, x^{\, \alpha-1}
|
| 2593 |
\; \mbox{.}$$
|
| 2594 |
|
| 2595 |
``` cpp
|
| 2596 |
template<class RealType = double>
|
| 2597 |
-
|
| 2598 |
-
{
|
| 2599 |
public:
|
| 2600 |
// types
|
| 2601 |
-
|
| 2602 |
-
|
| 2603 |
|
| 2604 |
// constructors and reset functions
|
| 2605 |
explicit gamma_distribution(RealType alpha = 1.0, RealType beta = 1.0);
|
| 2606 |
explicit gamma_distribution(const param_type& parm);
|
| 2607 |
void reset();
|
| 2608 |
|
| 2609 |
// generating functions
|
| 2610 |
-
|
| 2611 |
-
|
| 2612 |
-
|
| 2613 |
-
|
| 2614 |
|
| 2615 |
// property functions
|
| 2616 |
RealType alpha() const;
|
| 2617 |
RealType beta() const;
|
| 2618 |
param_type param() const;
|
|
@@ -2656,27 +2680,26 @@ $$%
|
|
| 2656 |
\cdot \, \exp\left( -\left(\frac{x}{b}\right)^a\right)
|
| 2657 |
\; \mbox{.}$$
|
| 2658 |
|
| 2659 |
``` cpp
|
| 2660 |
template<class RealType = double>
|
| 2661 |
-
|
| 2662 |
-
{
|
| 2663 |
public:
|
| 2664 |
// types
|
| 2665 |
-
|
| 2666 |
-
|
| 2667 |
|
| 2668 |
// constructor and reset functions
|
| 2669 |
explicit weibull_distribution(RealType a = 1.0, RealType b = 1.0);
|
| 2670 |
explicit weibull_distribution(const param_type& parm);
|
| 2671 |
void reset();
|
| 2672 |
|
| 2673 |
// generating functions
|
| 2674 |
-
|
| 2675 |
-
|
| 2676 |
-
|
| 2677 |
-
|
| 2678 |
|
| 2679 |
// property functions
|
| 2680 |
RealType a() const;
|
| 2681 |
RealType b() const;
|
| 2682 |
param_type param() const;
|
|
@@ -2721,27 +2744,26 @@ function[^6] $$%
|
|
| 2721 |
\right)
|
| 2722 |
\; \mbox{.}$$
|
| 2723 |
|
| 2724 |
``` cpp
|
| 2725 |
template<class RealType = double>
|
| 2726 |
-
|
| 2727 |
-
{
|
| 2728 |
public:
|
| 2729 |
// types
|
| 2730 |
-
|
| 2731 |
-
|
| 2732 |
|
| 2733 |
// constructor and reset functions
|
| 2734 |
explicit extreme_value_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 2735 |
explicit extreme_value_distribution(const param_type& parm);
|
| 2736 |
void reset();
|
| 2737 |
|
| 2738 |
// generating functions
|
| 2739 |
-
|
| 2740 |
-
|
| 2741 |
-
|
| 2742 |
-
|
| 2743 |
|
| 2744 |
// property functions
|
| 2745 |
RealType a() const;
|
| 2746 |
RealType b() const;
|
| 2747 |
param_type param() const;
|
|
@@ -2791,27 +2813,26 @@ numbers x distributed according to the probability density function $$%
|
|
| 2791 |
\; \mbox{.}$$ The distribution parameters μ and σ are also known as this
|
| 2792 |
distribution’s *mean* and *standard deviation* .
|
| 2793 |
|
| 2794 |
``` cpp
|
| 2795 |
template<class RealType = double>
|
| 2796 |
-
|
| 2797 |
-
{
|
| 2798 |
public:
|
| 2799 |
// types
|
| 2800 |
-
|
| 2801 |
-
|
| 2802 |
|
| 2803 |
// constructors and reset functions
|
| 2804 |
explicit normal_distribution(RealType mean = 0.0, RealType stddev = 1.0);
|
| 2805 |
explicit normal_distribution(const param_type& parm);
|
| 2806 |
void reset();
|
| 2807 |
|
| 2808 |
// generating functions
|
| 2809 |
-
|
| 2810 |
-
|
| 2811 |
-
|
| 2812 |
-
|
| 2813 |
|
| 2814 |
// property functions
|
| 2815 |
RealType mean() const;
|
| 2816 |
RealType stddev() const;
|
| 2817 |
param_type param() const;
|
|
@@ -2859,27 +2880,26 @@ $$%
|
|
| 2859 |
}
|
| 2860 |
\; \mbox{.}$$
|
| 2861 |
|
| 2862 |
``` cpp
|
| 2863 |
template<class RealType = double>
|
| 2864 |
-
|
| 2865 |
-
{
|
| 2866 |
public:
|
| 2867 |
// types
|
| 2868 |
-
|
| 2869 |
-
|
| 2870 |
|
| 2871 |
// constructor and reset functions
|
| 2872 |
explicit lognormal_distribution(RealType m = 0.0, RealType s = 1.0);
|
| 2873 |
explicit lognormal_distribution(const param_type& parm);
|
| 2874 |
void reset();
|
| 2875 |
|
| 2876 |
// generating functions
|
| 2877 |
-
|
| 2878 |
-
|
| 2879 |
-
|
| 2880 |
-
|
| 2881 |
|
| 2882 |
// property functions
|
| 2883 |
RealType m() const;
|
| 2884 |
RealType s() const;
|
| 2885 |
param_type param() const;
|
|
@@ -2922,27 +2942,26 @@ $$%
|
|
| 2922 |
{\Gamma(n/2) \cdot 2^{n/2}}
|
| 2923 |
\; \mbox{.}$$
|
| 2924 |
|
| 2925 |
``` cpp
|
| 2926 |
template<class RealType = double>
|
| 2927 |
-
|
| 2928 |
-
{
|
| 2929 |
public:
|
| 2930 |
// types
|
| 2931 |
-
|
| 2932 |
-
|
| 2933 |
|
| 2934 |
// constructor and reset functions
|
| 2935 |
explicit chi_squared_distribution(RealType n = 1);
|
| 2936 |
explicit chi_squared_distribution(const param_type& parm);
|
| 2937 |
void reset();
|
| 2938 |
|
| 2939 |
// generating functions
|
| 2940 |
-
|
| 2941 |
-
|
| 2942 |
-
|
| 2943 |
-
|
| 2944 |
|
| 2945 |
// property functions
|
| 2946 |
RealType n() const;
|
| 2947 |
param_type param() const;
|
| 2948 |
void param(const param_type& parm);
|
|
@@ -2975,27 +2994,26 @@ numbers x distributed according to the probability density function $$%
|
|
| 2975 |
= \left( \pi b \left( 1 + \left( \frac{x-a}{b} \right)^2 \;\right)\right)^{-1}
|
| 2976 |
\; \mbox{.}$$
|
| 2977 |
|
| 2978 |
``` cpp
|
| 2979 |
template<class RealType = double>
|
| 2980 |
-
|
| 2981 |
-
{
|
| 2982 |
public:
|
| 2983 |
// types
|
| 2984 |
-
|
| 2985 |
-
|
| 2986 |
|
| 2987 |
// constructor and reset functions
|
| 2988 |
explicit cauchy_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 2989 |
explicit cauchy_distribution(const param_type& parm);
|
| 2990 |
void reset();
|
| 2991 |
|
| 2992 |
// generating functions
|
| 2993 |
-
|
| 2994 |
-
|
| 2995 |
-
|
| 2996 |
-
|
| 2997 |
|
| 2998 |
// property functions
|
| 2999 |
RealType a() const;
|
| 3000 |
RealType b() const;
|
| 3001 |
param_type param() const;
|
|
@@ -3044,27 +3062,26 @@ $$%
|
|
| 3044 |
{\left( 1 + \frac{m x}{n} \right)}^{-(m+n)/2}
|
| 3045 |
\; \mbox{.}$$
|
| 3046 |
|
| 3047 |
``` cpp
|
| 3048 |
template<class RealType = double>
|
| 3049 |
-
|
| 3050 |
-
{
|
| 3051 |
public:
|
| 3052 |
// types
|
| 3053 |
-
|
| 3054 |
-
|
| 3055 |
|
| 3056 |
// constructor and reset functions
|
| 3057 |
explicit fisher_f_distribution(RealType m = 1, RealType n = 1);
|
| 3058 |
explicit fisher_f_distribution(const param_type& parm);
|
| 3059 |
void reset();
|
| 3060 |
|
| 3061 |
// generating functions
|
| 3062 |
-
|
| 3063 |
-
|
| 3064 |
-
|
| 3065 |
-
|
| 3066 |
|
| 3067 |
// property functions
|
| 3068 |
RealType m() const;
|
| 3069 |
RealType n() const;
|
| 3070 |
param_type param() const;
|
|
@@ -3109,27 +3126,26 @@ numbers x distributed according to the probability density function $$%
|
|
| 3109 |
\cdot \left( 1+\frac{x^2}{n} \right) ^ {-(n+1)/2}
|
| 3110 |
\; \mbox{.}$$
|
| 3111 |
|
| 3112 |
``` cpp
|
| 3113 |
template<class RealType = double>
|
| 3114 |
-
|
| 3115 |
-
{
|
| 3116 |
public:
|
| 3117 |
// types
|
| 3118 |
-
|
| 3119 |
-
|
| 3120 |
|
| 3121 |
// constructor and reset functions
|
| 3122 |
explicit student_t_distribution(RealType n = 1);
|
| 3123 |
explicit student_t_distribution(const param_type& parm);
|
| 3124 |
void reset();
|
| 3125 |
|
| 3126 |
// generating functions
|
| 3127 |
-
|
| 3128 |
-
|
| 3129 |
-
|
| 3130 |
-
|
| 3131 |
|
| 3132 |
// property functions
|
| 3133 |
RealType n() const;
|
| 3134 |
param_type param() const;
|
| 3135 |
void param(const param_type& parm);
|
|
@@ -3171,16 +3187,15 @@ the values wₖ, commonly known as the *weights* , shall be non-negative,
|
|
| 3171 |
non-NaN, and non-infinity. Moreover, the following relation shall hold:
|
| 3172 |
0 < S = w₀ + ⋯ + wₙ₋₁.
|
| 3173 |
|
| 3174 |
``` cpp
|
| 3175 |
template<class IntType = int>
|
| 3176 |
-
|
| 3177 |
-
{
|
| 3178 |
public:
|
| 3179 |
// types
|
| 3180 |
-
|
| 3181 |
-
|
| 3182 |
|
| 3183 |
// constructor and reset functions
|
| 3184 |
discrete_distribution();
|
| 3185 |
template<class InputIterator>
|
| 3186 |
discrete_distribution(InputIterator firstW, InputIterator lastW);
|
|
@@ -3189,14 +3204,14 @@ public:
|
|
| 3189 |
discrete_distribution(size_t nw, double xmin, double xmax, UnaryOperation fw);
|
| 3190 |
explicit discrete_distribution(const param_type& parm);
|
| 3191 |
void reset();
|
| 3192 |
|
| 3193 |
// generating functions
|
| 3194 |
-
|
| 3195 |
-
|
| 3196 |
-
|
| 3197 |
-
|
| 3198 |
|
| 3199 |
// property functions
|
| 3200 |
vector<double> probabilities() const;
|
| 3201 |
param_type param() const;
|
| 3202 |
void param(const param_type& parm);
|
|
@@ -3208,19 +3223,22 @@ public:
|
|
| 3208 |
``` cpp
|
| 3209 |
discrete_distribution();
|
| 3210 |
```
|
| 3211 |
|
| 3212 |
*Effects:* Constructs a `discrete_distribution` object with n = 1 and
|
| 3213 |
-
p₀ = 1.
|
|
|
|
|
|
|
|
|
|
| 3214 |
|
| 3215 |
``` cpp
|
| 3216 |
template<class InputIterator>
|
| 3217 |
discrete_distribution(InputIterator firstW, InputIterator lastW);
|
| 3218 |
```
|
| 3219 |
|
| 3220 |
*Requires:* `InputIterator` shall satisfy the requirements of an input
|
| 3221 |
-
iterator
|
| 3222 |
`iterator_traits<InputIterator>::value_type` shall denote a type that is
|
| 3223 |
convertible to `double`. If `firstW == lastW`, let n = 1 and w₀ = 1.
|
| 3224 |
Otherwise, [`firstW`, `lastW`) shall form a sequence w of length n > 0.
|
| 3225 |
|
| 3226 |
*Effects:* Constructs a `discrete_distribution` object with
|
|
@@ -3281,34 +3299,34 @@ commonly known as the *weights* , shall be non-negative, non-NaN, and
|
|
| 3281 |
non-infinity. Moreover, the following relation shall hold:
|
| 3282 |
0 < S = w₀ + ⋯ + wₙ₋₁.
|
| 3283 |
|
| 3284 |
``` cpp
|
| 3285 |
template<class RealType = double>
|
| 3286 |
-
|
| 3287 |
-
{
|
| 3288 |
public:
|
| 3289 |
// types
|
| 3290 |
-
|
| 3291 |
-
|
| 3292 |
|
| 3293 |
// constructor and reset functions
|
| 3294 |
piecewise_constant_distribution();
|
| 3295 |
template<class InputIteratorB, class InputIteratorW>
|
| 3296 |
piecewise_constant_distribution(InputIteratorB firstB, InputIteratorB lastB,
|
| 3297 |
InputIteratorW firstW);
|
| 3298 |
template<class UnaryOperation>
|
| 3299 |
piecewise_constant_distribution(initializer_list<RealType> bl, UnaryOperation fw);
|
| 3300 |
template<class UnaryOperation>
|
| 3301 |
-
|
|
|
|
| 3302 |
explicit piecewise_constant_distribution(const param_type& parm);
|
| 3303 |
void reset();
|
| 3304 |
|
| 3305 |
// generating functions
|
| 3306 |
-
|
| 3307 |
-
|
| 3308 |
-
|
| 3309 |
-
|
| 3310 |
|
| 3311 |
// property functions
|
| 3312 |
vector<result_type> intervals() const;
|
| 3313 |
vector<result_type> densities() const;
|
| 3314 |
param_type param() const;
|
|
@@ -3421,16 +3439,15 @@ relation shall hold: $$%
|
|
| 3421 |
\cdot \sum_{k=0}^{n-1} (w_k + w_{k+1}) \cdot (b_{k+1} - b_k)
|
| 3422 |
\; \mbox{.}$$
|
| 3423 |
|
| 3424 |
``` cpp
|
| 3425 |
template<class RealType = double>
|
| 3426 |
-
|
| 3427 |
-
{
|
| 3428 |
public:
|
| 3429 |
// types
|
| 3430 |
-
|
| 3431 |
-
|
| 3432 |
|
| 3433 |
// constructor and reset functions
|
| 3434 |
piecewise_linear_distribution();
|
| 3435 |
template<class InputIteratorB, class InputIteratorW>
|
| 3436 |
piecewise_linear_distribution(InputIteratorB firstB, InputIteratorB lastB,
|
|
@@ -3441,14 +3458,14 @@ public:
|
|
| 3441 |
piecewise_linear_distribution(size_t nw, RealType xmin, RealType xmax, UnaryOperation fw);
|
| 3442 |
explicit piecewise_linear_distribution(const param_type& parm);
|
| 3443 |
void reset();
|
| 3444 |
|
| 3445 |
// generating functions
|
| 3446 |
-
|
| 3447 |
-
|
| 3448 |
-
|
| 3449 |
-
|
| 3450 |
|
| 3451 |
// property functions
|
| 3452 |
vector<result_type> intervals() const;
|
| 3453 |
vector<result_type> densities() const;
|
| 3454 |
param_type param() const;
|
|
@@ -3534,19 +3551,43 @@ vector<result_type> densities() const;
|
|
| 3534 |
|
| 3535 |
*Returns:* A `vector<result_type>` whose `size` member returns n and
|
| 3536 |
whose `operator[]` member returns ρₖ when invoked with argument k for
|
| 3537 |
k = 0, …, n.
|
| 3538 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 3539 |
## Numeric arrays <a id="numarray">[[numarray]]</a>
|
| 3540 |
|
| 3541 |
### Header `<valarray>` synopsis <a id="valarray.syn">[[valarray.syn]]</a>
|
| 3542 |
|
| 3543 |
``` cpp
|
| 3544 |
#include <initializer_list>
|
| 3545 |
|
| 3546 |
namespace std {
|
| 3547 |
-
|
| 3548 |
template<class T> class valarray; // An array of type T
|
| 3549 |
class slice; // a BLAS-like slice out of an array
|
| 3550 |
template<class T> class slice_array;
|
| 3551 |
class gslice; // a generalized slice out of an array
|
| 3552 |
template<class T> class gslice_array;
|
|
@@ -3685,11 +3726,11 @@ additional functions and operators as follows:
|
|
| 3685 |
identical functions taking every combination of `const valarray<T>&`
|
| 3686 |
and replacement types shall be added.
|
| 3687 |
|
| 3688 |
In particular, an implementation shall allow a `valarray<T>` to be
|
| 3689 |
constructed from such replacement types and shall allow assignments and
|
| 3690 |
-
|
| 3691 |
`gslice_array<T>`, `mask_array<T>` and `indirect_array<T>` objects.
|
| 3692 |
|
| 3693 |
These library functions are permitted to throw a `bad_alloc` (
|
| 3694 |
[[bad.alloc]]) exception if there are not sufficient resources available
|
| 3695 |
to carry out the operation. Note that the exception is not mandated.
|
|
@@ -3700,13 +3741,13 @@ to carry out the operation. Note that the exception is not mandated.
|
|
| 3700 |
|
| 3701 |
``` cpp
|
| 3702 |
namespace std {
|
| 3703 |
template<class T> class valarray {
|
| 3704 |
public:
|
| 3705 |
-
|
| 3706 |
|
| 3707 |
-
// [valarray.cons] construct/destroy
|
| 3708 |
valarray();
|
| 3709 |
explicit valarray(size_t);
|
| 3710 |
valarray(const T&, size_t);
|
| 3711 |
valarray(const T*, size_t);
|
| 3712 |
valarray(const valarray&);
|
|
@@ -3716,149 +3757,151 @@ namespace std {
|
|
| 3716 |
valarray(const mask_array<T>&);
|
| 3717 |
valarray(const indirect_array<T>&);
|
| 3718 |
valarray(initializer_list<T>);
|
| 3719 |
~valarray();
|
| 3720 |
|
| 3721 |
-
// [valarray.assign] assignment
|
| 3722 |
-
valarray
|
| 3723 |
-
valarray
|
| 3724 |
valarray& operator=(initializer_list<T>);
|
| 3725 |
-
valarray
|
| 3726 |
-
valarray
|
| 3727 |
-
valarray
|
| 3728 |
-
valarray
|
| 3729 |
-
valarray
|
| 3730 |
|
| 3731 |
-
// [valarray.access] element access
|
| 3732 |
const T& operator[](size_t) const;
|
| 3733 |
T& operator[](size_t);
|
| 3734 |
|
| 3735 |
-
// [valarray.sub] subset operations
|
| 3736 |
-
valarray
|
| 3737 |
slice_array<T> operator[](slice);
|
| 3738 |
-
valarray
|
| 3739 |
gslice_array<T> operator[](const gslice&);
|
| 3740 |
-
valarray
|
| 3741 |
mask_array<T> operator[](const valarray<bool>&);
|
| 3742 |
-
valarray
|
| 3743 |
indirect_array<T> operator[](const valarray<size_t>&);
|
| 3744 |
|
| 3745 |
-
// [valarray.unary] unary operators
|
| 3746 |
-
valarray
|
| 3747 |
-
valarray
|
| 3748 |
-
valarray
|
| 3749 |
valarray<bool> operator!() const;
|
| 3750 |
|
| 3751 |
-
// [valarray.cassign]
|
| 3752 |
-
valarray
|
| 3753 |
-
valarray
|
| 3754 |
-
valarray
|
| 3755 |
-
valarray
|
| 3756 |
-
valarray
|
| 3757 |
-
valarray
|
| 3758 |
-
valarray
|
| 3759 |
-
valarray
|
| 3760 |
-
valarray
|
| 3761 |
-
valarray
|
| 3762 |
|
| 3763 |
-
valarray
|
| 3764 |
-
valarray
|
| 3765 |
-
valarray
|
| 3766 |
-
valarray
|
| 3767 |
-
valarray
|
| 3768 |
-
valarray
|
| 3769 |
-
valarray
|
| 3770 |
-
valarray
|
| 3771 |
-
valarray
|
| 3772 |
-
valarray
|
| 3773 |
|
| 3774 |
-
// [valarray.members] member functions
|
| 3775 |
void swap(valarray&) noexcept;
|
| 3776 |
|
| 3777 |
size_t size() const;
|
| 3778 |
|
| 3779 |
T sum() const;
|
| 3780 |
T min() const;
|
| 3781 |
T max() const;
|
| 3782 |
|
| 3783 |
-
valarray
|
| 3784 |
-
valarray
|
| 3785 |
-
valarray
|
| 3786 |
-
valarray
|
| 3787 |
void resize(size_t sz, T c = T());
|
| 3788 |
};
|
|
|
|
|
|
|
| 3789 |
}
|
| 3790 |
```
|
| 3791 |
|
| 3792 |
The class template `valarray<T>` is a one-dimensional smart array, with
|
| 3793 |
elements numbered sequentially from zero. It is a representation of the
|
| 3794 |
-
mathematical concept of an ordered set of values.
|
| 3795 |
-
|
| 3796 |
-
|
| 3797 |
-
the
|
|
|
|
|
|
|
| 3798 |
|
| 3799 |
An implementation is permitted to qualify any of the functions declared
|
| 3800 |
in `<valarray>` as `inline`.
|
| 3801 |
|
| 3802 |
#### `valarray` constructors <a id="valarray.cons">[[valarray.cons]]</a>
|
| 3803 |
|
| 3804 |
``` cpp
|
| 3805 |
valarray();
|
| 3806 |
```
|
| 3807 |
|
| 3808 |
-
*Effects:* Constructs
|
| 3809 |
-
zero length.[^10]
|
| 3810 |
|
| 3811 |
``` cpp
|
| 3812 |
-
explicit valarray(size_t);
|
| 3813 |
```
|
| 3814 |
|
| 3815 |
-
|
| 3816 |
-
the
|
| 3817 |
-
value-initialized ([[dcl.init]]).
|
| 3818 |
|
| 3819 |
``` cpp
|
| 3820 |
-
valarray(const T&, size_t);
|
| 3821 |
```
|
| 3822 |
|
| 3823 |
-
|
| 3824 |
-
|
| 3825 |
-
the first argument.
|
| 3826 |
|
| 3827 |
``` cpp
|
| 3828 |
-
valarray(const T*, size_t);
|
| 3829 |
```
|
| 3830 |
|
| 3831 |
-
|
| 3832 |
-
|
| 3833 |
-
|
| 3834 |
-
|
| 3835 |
-
|
|
|
|
| 3836 |
|
| 3837 |
``` cpp
|
| 3838 |
-
valarray(const valarray
|
| 3839 |
```
|
| 3840 |
|
| 3841 |
-
|
| 3842 |
-
|
| 3843 |
-
|
| 3844 |
|
| 3845 |
``` cpp
|
| 3846 |
-
valarray(valarray
|
| 3847 |
```
|
| 3848 |
|
| 3849 |
-
|
| 3850 |
-
|
| 3851 |
-
|
| 3852 |
|
| 3853 |
*Complexity:* Constant.
|
| 3854 |
|
| 3855 |
``` cpp
|
| 3856 |
valarray(initializer_list<T> il);
|
| 3857 |
```
|
| 3858 |
|
| 3859 |
-
*Effects:*
|
| 3860 |
|
| 3861 |
``` cpp
|
| 3862 |
valarray(const slice_array<T>&);
|
| 3863 |
valarray(const gslice_array<T>&);
|
| 3864 |
valarray(const mask_array<T>&);
|
|
@@ -3870,101 +3913,103 @@ templates to a `valarray`.
|
|
| 3870 |
|
| 3871 |
``` cpp
|
| 3872 |
~valarray();
|
| 3873 |
```
|
| 3874 |
|
| 3875 |
-
The destructor is applied to every element of `*this`; an
|
| 3876 |
-
may return all allocated memory.
|
| 3877 |
|
| 3878 |
#### `valarray` assignment <a id="valarray.assign">[[valarray.assign]]</a>
|
| 3879 |
|
| 3880 |
``` cpp
|
| 3881 |
-
valarray
|
| 3882 |
```
|
| 3883 |
|
| 3884 |
-
Each element of the `*this` array is assigned the value of
|
| 3885 |
-
corresponding element of
|
| 3886 |
-
|
| 3887 |
-
|
| 3888 |
-
|
| 3889 |
|
| 3890 |
-
`size() == v.size()`.
|
|
|
|
|
|
|
| 3891 |
|
| 3892 |
``` cpp
|
| 3893 |
-
valarray
|
| 3894 |
```
|
| 3895 |
|
| 3896 |
*Effects:* `*this` obtains the value of `v`. The value of `v` after the
|
| 3897 |
assignment is not specified.
|
| 3898 |
|
|
|
|
|
|
|
| 3899 |
*Complexity:* Linear.
|
| 3900 |
|
| 3901 |
``` cpp
|
| 3902 |
valarray& operator=(initializer_list<T> il);
|
| 3903 |
```
|
| 3904 |
|
| 3905 |
-
*Effects:* `*this = valarray(il)`
|
| 3906 |
-
|
| 3907 |
-
*Returns:* `*this`.
|
| 3908 |
|
| 3909 |
``` cpp
|
| 3910 |
-
valarray
|
| 3911 |
```
|
| 3912 |
|
| 3913 |
-
|
| 3914 |
-
|
|
|
|
| 3915 |
|
| 3916 |
``` cpp
|
| 3917 |
-
valarray
|
| 3918 |
-
valarray
|
| 3919 |
-
valarray
|
| 3920 |
-
valarray
|
| 3921 |
```
|
| 3922 |
|
| 3923 |
*Requires:* The length of the array to which the argument refers equals
|
| 3924 |
-
`size()`.
|
|
|
|
|
|
|
| 3925 |
|
| 3926 |
These operators allow the results of a generalized subscripting
|
| 3927 |
operation to be assigned directly to a `valarray`.
|
| 3928 |
|
| 3929 |
-
If the value of an element in the left-hand side of a valarray
|
| 3930 |
-
assignment operator depends on the value of another element in that
|
| 3931 |
-
left-hand side, the resulting behavior is undefined.
|
| 3932 |
-
|
| 3933 |
#### `valarray` element access <a id="valarray.access">[[valarray.access]]</a>
|
| 3934 |
|
| 3935 |
``` cpp
|
| 3936 |
-
const T& operator[](size_t) const;
|
| 3937 |
-
T& operator[](size_t);
|
| 3938 |
```
|
| 3939 |
|
| 3940 |
-
|
| 3941 |
-
of the array.
|
| 3942 |
|
| 3943 |
-
|
| 3944 |
-
non-constant `valarray<T> a`, any `T q`, and for any `size_t i` such
|
| 3945 |
-
that the value of `i` is less than the length of `a`.
|
| 3946 |
|
| 3947 |
-
The expression `
|
| 3948 |
-
|
| 3949 |
-
|
|
|
|
| 3950 |
|
| 3951 |
-
|
| 3952 |
-
|
| 3953 |
-
|
| 3954 |
-
|
| 3955 |
-
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 3956 |
|
| 3957 |
The reference returned by the subscript operator for an array shall be
|
| 3958 |
valid until the member function
|
| 3959 |
`resize(size_t, T)` ([[valarray.members]]) is called for that array or
|
| 3960 |
until the lifetime of that array ends, whichever happens first.
|
| 3961 |
|
| 3962 |
-
If the subscript operator is invoked with a `size_t` argument whose
|
| 3963 |
-
value is not less than the length of the array, the behavior is
|
| 3964 |
-
undefined.
|
| 3965 |
-
|
| 3966 |
#### `valarray` subset operations <a id="valarray.sub">[[valarray.sub]]</a>
|
| 3967 |
|
| 3968 |
The member `operator[]` is overloaded to provide several ways to select
|
| 3969 |
sequences of elements from among those controlled by `*this`. Each of
|
| 3970 |
these operations returns a subset of the array. The const-qualified
|
|
@@ -3974,200 +4019,231 @@ the original array, working in conjunction with various overloads of
|
|
| 3974 |
`operator=` and other assigning operators to allow selective replacement
|
| 3975 |
(slicing) of the controlled sequence. In each case the selected
|
| 3976 |
element(s) must exist.
|
| 3977 |
|
| 3978 |
``` cpp
|
| 3979 |
-
valarray
|
| 3980 |
```
|
| 3981 |
|
| 3982 |
-
*Returns:*
|
| 3983 |
-
|
|
|
|
|
|
|
| 3984 |
|
| 3985 |
``` cpp
|
| 3986 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 3987 |
// v0[slice(2, 5, 3)] returns valarray<char>("cfilo", 5)
|
| 3988 |
```
|
| 3989 |
|
|
|
|
|
|
|
| 3990 |
``` cpp
|
| 3991 |
slice_array<T> operator[](slice slicearr);
|
| 3992 |
```
|
| 3993 |
|
| 3994 |
*Returns:* An object that holds references to elements of the controlled
|
| 3995 |
sequence selected by `slicearr`.
|
| 3996 |
|
|
|
|
|
|
|
| 3997 |
``` cpp
|
| 3998 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 3999 |
valarray<char> v1("ABCDE", 5);
|
| 4000 |
v0[slice(2, 5, 3)] = v1;
|
| 4001 |
// v0 == valarray<char>("abAdeBghCjkDmnEp", 16);
|
| 4002 |
```
|
| 4003 |
|
|
|
|
|
|
|
| 4004 |
``` cpp
|
| 4005 |
-
valarray
|
| 4006 |
```
|
| 4007 |
|
| 4008 |
-
*Returns:*
|
| 4009 |
-
|
|
|
|
|
|
|
| 4010 |
|
| 4011 |
``` cpp
|
| 4012 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4013 |
const size_t lv[] = { 2, 3 };
|
| 4014 |
const size_t dv[] = { 7, 2 };
|
| 4015 |
const valarray<size_t> len(lv, 2), str(dv, 2);
|
| 4016 |
// v0[gslice(3, len, str)] returns
|
| 4017 |
// valarray<char>("dfhkmo", 6)
|
| 4018 |
```
|
| 4019 |
|
|
|
|
|
|
|
| 4020 |
``` cpp
|
| 4021 |
gslice_array<T> operator[](const gslice& gslicearr);
|
| 4022 |
```
|
| 4023 |
|
| 4024 |
*Returns:* An object that holds references to elements of the controlled
|
| 4025 |
sequence selected by `gslicearr`.
|
| 4026 |
|
|
|
|
|
|
|
| 4027 |
``` cpp
|
| 4028 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4029 |
-
valarray<char> v1("
|
| 4030 |
const size_t lv[] = { 2, 3 };
|
| 4031 |
const size_t dv[] = { 7, 2 };
|
| 4032 |
const valarray<size_t> len(lv, 2), str(dv, 2);
|
| 4033 |
v0[gslice(3, len, str)] = v1;
|
| 4034 |
// v0 == valarray<char>("abcAeBgCijDlEnFp", 16)
|
| 4035 |
```
|
| 4036 |
|
|
|
|
|
|
|
| 4037 |
``` cpp
|
| 4038 |
-
valarray
|
| 4039 |
```
|
| 4040 |
|
| 4041 |
-
*Returns:*
|
| 4042 |
-
|
|
|
|
|
|
|
| 4043 |
|
| 4044 |
``` cpp
|
| 4045 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4046 |
const bool vb[] = { false, false, true, true, false, true };
|
| 4047 |
// v0[valarray<bool>(vb, 6)] returns
|
| 4048 |
// valarray<char>("cdf", 3)
|
| 4049 |
```
|
| 4050 |
|
|
|
|
|
|
|
| 4051 |
``` cpp
|
| 4052 |
mask_array<T> operator[](const valarray<bool>& boolarr);
|
| 4053 |
```
|
| 4054 |
|
| 4055 |
*Returns:* An object that holds references to elements of the controlled
|
| 4056 |
sequence selected by `boolarr`.
|
| 4057 |
|
|
|
|
|
|
|
| 4058 |
``` cpp
|
| 4059 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4060 |
valarray<char> v1("ABC", 3);
|
| 4061 |
const bool vb[] = { false, false, true, true, false, true };
|
| 4062 |
v0[valarray<bool>(vb, 6)] = v1;
|
| 4063 |
// v0 == valarray<char>("abABeCghijklmnop", 16)
|
| 4064 |
```
|
| 4065 |
|
|
|
|
|
|
|
| 4066 |
``` cpp
|
| 4067 |
-
valarray
|
| 4068 |
```
|
| 4069 |
|
| 4070 |
-
*Returns:*
|
| 4071 |
-
|
|
|
|
|
|
|
| 4072 |
|
| 4073 |
``` cpp
|
| 4074 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4075 |
const size_t vi[] = { 7, 5, 2, 3, 8 };
|
| 4076 |
// v0[valarray<size_t>(vi, 5)] returns
|
| 4077 |
// valarray<char>("hfcdi", 5)
|
| 4078 |
```
|
| 4079 |
|
|
|
|
|
|
|
| 4080 |
``` cpp
|
| 4081 |
indirect_array<T> operator[](const valarray<size_t>& indarr);
|
| 4082 |
```
|
| 4083 |
|
| 4084 |
*Returns:* An object that holds references to elements of the controlled
|
| 4085 |
sequence selected by `indarr`.
|
| 4086 |
|
|
|
|
|
|
|
| 4087 |
``` cpp
|
| 4088 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4089 |
valarray<char> v1("ABCDE", 5);
|
| 4090 |
const size_t vi[] = { 7, 5, 2, 3, 8 };
|
| 4091 |
v0[valarray<size_t>(vi, 5)] = v1;
|
| 4092 |
// v0 == valarray<char>("abCDeBgAEjklmnop", 16)
|
| 4093 |
```
|
| 4094 |
|
|
|
|
|
|
|
| 4095 |
#### `valarray` unary operators <a id="valarray.unary">[[valarray.unary]]</a>
|
| 4096 |
|
| 4097 |
``` cpp
|
| 4098 |
-
valarray
|
| 4099 |
-
valarray
|
| 4100 |
-
valarray
|
| 4101 |
valarray<bool> operator!() const;
|
| 4102 |
```
|
| 4103 |
|
| 4104 |
-
Each of these operators may only be instantiated for a type
|
| 4105 |
-
the indicated operator can be applied and for which the
|
| 4106 |
-
operator returns a value which is of type `T` (`bool` for
|
| 4107 |
-
or which may be unambiguously implicitly converted to type
|
| 4108 |
-
for `operator!`).
|
| 4109 |
|
| 4110 |
-
|
| 4111 |
-
|
| 4112 |
-
|
| 4113 |
-
element of the array.
|
| 4114 |
|
| 4115 |
-
#### `valarray`
|
| 4116 |
|
| 4117 |
``` cpp
|
| 4118 |
-
valarray
|
| 4119 |
-
valarray
|
| 4120 |
-
valarray
|
| 4121 |
-
valarray
|
| 4122 |
-
valarray
|
| 4123 |
-
valarray
|
| 4124 |
-
valarray
|
| 4125 |
-
valarray
|
| 4126 |
-
valarray
|
| 4127 |
-
valarray
|
| 4128 |
```
|
| 4129 |
|
| 4130 |
-
Each of these operators may only be
|
| 4131 |
-
the indicated operator can be applied
|
| 4132 |
-
|
| 4133 |
-
|
|
|
|
| 4134 |
|
| 4135 |
-
|
|
|
|
| 4136 |
|
| 4137 |
-
|
| 4138 |
-
behavior is undefined. The appearance of an array on the left-hand side
|
| 4139 |
-
of a computed assignment does `not` invalidate references or pointers.
|
| 4140 |
|
| 4141 |
-
|
| 4142 |
-
assignment
|
| 4143 |
-
hand side, the resulting behavior is undefined.
|
| 4144 |
|
| 4145 |
``` cpp
|
| 4146 |
-
valarray
|
| 4147 |
-
valarray
|
| 4148 |
-
valarray
|
| 4149 |
-
valarray
|
| 4150 |
-
valarray
|
| 4151 |
-
valarray
|
| 4152 |
-
valarray
|
| 4153 |
-
valarray
|
| 4154 |
-
valarray
|
| 4155 |
-
valarray
|
| 4156 |
```
|
| 4157 |
|
| 4158 |
-
Each of these operators may only be instantiated for a type
|
| 4159 |
-
the indicated operator can be applied
|
|
|
|
| 4160 |
|
| 4161 |
-
Each of these operators applies the indicated operation to
|
| 4162 |
-
|
| 4163 |
|
| 4164 |
-
|
| 4165 |
|
| 4166 |
-
The appearance of an array on the left-hand side of a
|
| 4167 |
-
assignment does
|
| 4168 |
-
of the array.
|
| 4169 |
|
| 4170 |
#### `valarray` member functions <a id="valarray.members">[[valarray.members]]</a>
|
| 4171 |
|
| 4172 |
``` cpp
|
| 4173 |
void swap(valarray& v) noexcept;
|
|
@@ -4188,55 +4264,81 @@ size_t size() const;
|
|
| 4188 |
|
| 4189 |
``` cpp
|
| 4190 |
T sum() const;
|
| 4191 |
```
|
| 4192 |
|
| 4193 |
-
This function may only be instantiated for a
|
| 4194 |
-
`operator+=` can be applied.
|
| 4195 |
-
elements of the array.
|
| 4196 |
|
| 4197 |
-
|
| 4198 |
-
length 1,
|
| 4199 |
-
|
| 4200 |
-
|
| 4201 |
-
unspecified order.
|
| 4202 |
|
| 4203 |
``` cpp
|
| 4204 |
T min() const;
|
| 4205 |
```
|
| 4206 |
|
| 4207 |
-
|
| 4208 |
-
|
| 4209 |
-
|
| 4210 |
-
|
|
|
|
| 4211 |
|
| 4212 |
``` cpp
|
| 4213 |
T max() const;
|
| 4214 |
```
|
| 4215 |
|
| 4216 |
-
|
| 4217 |
-
|
| 4218 |
-
|
| 4219 |
-
|
|
|
|
| 4220 |
|
| 4221 |
``` cpp
|
| 4222 |
-
valarray
|
| 4223 |
```
|
| 4224 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4225 |
``` cpp
|
| 4226 |
-
valarray
|
| 4227 |
```
|
| 4228 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4229 |
``` cpp
|
| 4230 |
-
valarray
|
| 4231 |
-
valarray
|
| 4232 |
```
|
| 4233 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4234 |
``` cpp
|
| 4235 |
void resize(size_t sz, T c = T());
|
| 4236 |
```
|
| 4237 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4238 |
### `valarray` non-member operations <a id="valarray.nonmembers">[[valarray.nonmembers]]</a>
|
| 4239 |
|
| 4240 |
#### `valarray` binary operators <a id="valarray.binary">[[valarray.binary]]</a>
|
| 4241 |
|
| 4242 |
``` cpp
|
|
@@ -4260,22 +4362,20 @@ template<class T> valarray<T> operator<<
|
|
| 4260 |
(const valarray<T>&, const valarray<T>&);
|
| 4261 |
template<class T> valarray<T> operator>>
|
| 4262 |
(const valarray<T>&, const valarray<T>&);
|
| 4263 |
```
|
| 4264 |
|
| 4265 |
-
Each of these operators may only be instantiated for a type
|
| 4266 |
-
the indicated operator can be applied and for which the
|
| 4267 |
-
operator returns a value which is of type `T` or which can be
|
| 4268 |
-
unambiguously implicitly converted to type `T`.
|
|
|
|
| 4269 |
|
| 4270 |
-
|
| 4271 |
-
|
| 4272 |
-
|
| 4273 |
-
|
| 4274 |
-
|
| 4275 |
-
If the argument arrays do not have the same length, the behavior is
|
| 4276 |
-
undefined.
|
| 4277 |
|
| 4278 |
``` cpp
|
| 4279 |
template<class T> valarray<T> operator* (const valarray<T>&, const T&);
|
| 4280 |
template<class T> valarray<T> operator* (const T&, const valarray<T>&);
|
| 4281 |
template<class T> valarray<T> operator/ (const valarray<T>&, const T&);
|
|
@@ -4296,19 +4396,19 @@ template<class T> valarray<T> operator<<(const valarray<T>&, const T&);
|
|
| 4296 |
template<class T> valarray<T> operator<<(const T&, const valarray<T>&);
|
| 4297 |
template<class T> valarray<T> operator>>(const valarray<T>&, const T&);
|
| 4298 |
template<class T> valarray<T> operator>>(const T&, const valarray<T>&);
|
| 4299 |
```
|
| 4300 |
|
| 4301 |
-
Each of these operators may only be instantiated for a type
|
| 4302 |
-
the indicated operator can be applied and for which the
|
| 4303 |
-
operator returns a value which is of type `T` or which can be
|
| 4304 |
unambiguously implicitly converted to type `T`.
|
| 4305 |
|
| 4306 |
-
|
| 4307 |
-
|
| 4308 |
-
|
| 4309 |
-
|
| 4310 |
|
| 4311 |
#### `valarray` logical operators <a id="valarray.comparison">[[valarray.comparison]]</a>
|
| 4312 |
|
| 4313 |
``` cpp
|
| 4314 |
template<class T> valarray<bool> operator==
|
|
@@ -4327,22 +4427,20 @@ template<class T> valarray<bool> operator&&
|
|
| 4327 |
(const valarray<T>&, const valarray<T>&);
|
| 4328 |
template<class T> valarray<bool> operator||
|
| 4329 |
(const valarray<T>&, const valarray<T>&);
|
| 4330 |
```
|
| 4331 |
|
| 4332 |
-
Each of these operators may only be instantiated for a type
|
| 4333 |
-
the indicated operator can be applied and for which the
|
| 4334 |
-
operator returns a value which is of type `bool` or which can
|
| 4335 |
-
unambiguously implicitly converted to type `bool`.
|
|
|
|
| 4336 |
|
| 4337 |
-
|
| 4338 |
-
|
| 4339 |
-
|
| 4340 |
-
|
| 4341 |
-
|
| 4342 |
-
If the two array arguments do not have the same length, the behavior is
|
| 4343 |
-
undefined.
|
| 4344 |
|
| 4345 |
``` cpp
|
| 4346 |
template<class T> valarray<bool> operator==(const valarray<T>&, const T&);
|
| 4347 |
template<class T> valarray<bool> operator==(const T&, const valarray<T>&);
|
| 4348 |
template<class T> valarray<bool> operator!=(const valarray<T>&, const T&);
|
|
@@ -4359,19 +4457,19 @@ template<class T> valarray<bool> operator&&(const valarray<T>&, const T&);
|
|
| 4359 |
template<class T> valarray<bool> operator&&(const T&, const valarray<T>&);
|
| 4360 |
template<class T> valarray<bool> operator||(const valarray<T>&, const T&);
|
| 4361 |
template<class T> valarray<bool> operator||(const T&, const valarray<T>&);
|
| 4362 |
```
|
| 4363 |
|
| 4364 |
-
Each of these operators may only be instantiated for a type
|
| 4365 |
-
the indicated operator can be applied and for which the
|
| 4366 |
-
operator returns a value which is of type `bool` or which can
|
| 4367 |
-
unambiguously implicitly converted to type `bool`.
|
| 4368 |
|
| 4369 |
-
|
| 4370 |
-
|
| 4371 |
-
|
| 4372 |
-
|
| 4373 |
|
| 4374 |
#### `valarray` transcendentals <a id="valarray.transcend">[[valarray.transcend]]</a>
|
| 4375 |
|
| 4376 |
``` cpp
|
| 4377 |
template<class T> valarray<T> abs (const valarray<T>&);
|
|
@@ -4396,22 +4494,22 @@ template<class T> valarray<T> sinh (const valarray<T>&);
|
|
| 4396 |
template<class T> valarray<T> sqrt (const valarray<T>&);
|
| 4397 |
template<class T> valarray<T> tan (const valarray<T>&);
|
| 4398 |
template<class T> valarray<T> tanh (const valarray<T>&);
|
| 4399 |
```
|
| 4400 |
|
| 4401 |
-
Each of these functions may only be instantiated for a type
|
| 4402 |
-
a unique function with the indicated name can be applied
|
| 4403 |
-
This function shall return a value which is of type `T`
|
| 4404 |
-
unambiguously implicitly converted to type `T`.
|
| 4405 |
|
| 4406 |
#### `valarray` specialized algorithms <a id="valarray.special">[[valarray.special]]</a>
|
| 4407 |
|
| 4408 |
``` cpp
|
| 4409 |
template <class T> void swap(valarray<T>& x, valarray<T>& y) noexcept;
|
| 4410 |
```
|
| 4411 |
|
| 4412 |
-
*Effects:* `x.swap(y)`.
|
| 4413 |
|
| 4414 |
### Class `slice` <a id="class.slice">[[class.slice]]</a>
|
| 4415 |
|
| 4416 |
#### Class `slice` overview <a id="class.slice.overview">[[class.slice.overview]]</a>
|
| 4417 |
|
|
@@ -4428,11 +4526,11 @@ namespace std {
|
|
| 4428 |
};
|
| 4429 |
}
|
| 4430 |
```
|
| 4431 |
|
| 4432 |
The `slice` class represents a BLAS-like slice from an array. Such a
|
| 4433 |
-
slice is specified by a starting index, a length, and a stride.[^
|
| 4434 |
|
| 4435 |
#### `slice` constructors <a id="cons.slice">[[cons.slice]]</a>
|
| 4436 |
|
| 4437 |
``` cpp
|
| 4438 |
slice();
|
|
@@ -4443,12 +4541,12 @@ slice(const slice&);
|
|
| 4443 |
The default constructor is equivalent to `slice(0, 0, 0)`. A default
|
| 4444 |
constructor is provided only to permit the declaration of arrays of
|
| 4445 |
slices. The constructor with arguments for a slice takes a start,
|
| 4446 |
length, and stride parameter.
|
| 4447 |
|
| 4448 |
-
`slice(3, 8, 2)` constructs a slice which selects
|
| 4449 |
-
17 from an array.
|
| 4450 |
|
| 4451 |
#### `slice` access functions <a id="slice.access">[[slice.access]]</a>
|
| 4452 |
|
| 4453 |
``` cpp
|
| 4454 |
size_t start() const;
|
|
@@ -4466,11 +4564,11 @@ size_t stride() const;
|
|
| 4466 |
|
| 4467 |
``` cpp
|
| 4468 |
namespace std {
|
| 4469 |
template <class T> class slice_array {
|
| 4470 |
public:
|
| 4471 |
-
|
| 4472 |
|
| 4473 |
void operator= (const valarray<T>&) const;
|
| 4474 |
void operator*= (const valarray<T>&) const;
|
| 4475 |
void operator/= (const valarray<T>&) const;
|
| 4476 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4500,13 +4598,14 @@ slice_array<T> valarray<T>::operator[](slice);
|
|
| 4500 |
```
|
| 4501 |
|
| 4502 |
It has reference semantics to a subset of an array specified by a
|
| 4503 |
`slice` object.
|
| 4504 |
|
| 4505 |
-
The expression `a[slice(1, 5, 3)] = b;` has the effect of
|
| 4506 |
-
elements of `b` to a slice of the elements in `a`. For the
|
| 4507 |
-
the elements selected from `a` are 1, 4, ...,
|
|
|
|
| 4508 |
|
| 4509 |
#### `slice_array` assignment <a id="slice.arr.assign">[[slice.arr.assign]]</a>
|
| 4510 |
|
| 4511 |
``` cpp
|
| 4512 |
void operator=(const valarray<T>&) const;
|
|
@@ -4515,11 +4614,11 @@ const slice_array& operator=(const slice_array&) const;
|
|
| 4515 |
|
| 4516 |
These assignment operators have reference semantics, assigning the
|
| 4517 |
values of the argument array elements to selected elements of the
|
| 4518 |
`valarray<T>` object to which the `slice_array` object refers.
|
| 4519 |
|
| 4520 |
-
#### `slice_array`
|
| 4521 |
|
| 4522 |
``` cpp
|
| 4523 |
void operator*= (const valarray<T>&) const;
|
| 4524 |
void operator/= (const valarray<T>&) const;
|
| 4525 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4530,11 +4629,11 @@ void operator&= (const valarray<T>&) const;
|
|
| 4530 |
void operator|= (const valarray<T>&) const;
|
| 4531 |
void operator<<=(const valarray<T>&) const;
|
| 4532 |
void operator>>=(const valarray<T>&) const;
|
| 4533 |
```
|
| 4534 |
|
| 4535 |
-
These
|
| 4536 |
indicated operation to the elements of the argument array and selected
|
| 4537 |
elements of the `valarray<T>` object to which the `slice_array` object
|
| 4538 |
refers.
|
| 4539 |
|
| 4540 |
#### `slice_array` fill function <a id="slice.arr.fill">[[slice.arr.fill]]</a>
|
|
@@ -4574,34 +4673,40 @@ number to the number of strides, to a single index k. It is useful for
|
|
| 4574 |
building multidimensional array classes using the `valarray` template,
|
| 4575 |
which is one-dimensional. The set of one-dimensional index values
|
| 4576 |
specified by a `gslice` are $$k = s + \sum_j i_j d_j$$ where the
|
| 4577 |
multidimensional indices iⱼ range in value from 0 to lᵢⱼ - 1.
|
| 4578 |
|
|
|
|
|
|
|
| 4579 |
The `gslice` specification
|
| 4580 |
|
| 4581 |
``` cpp
|
| 4582 |
start = 3
|
| 4583 |
length = {2, 4, 3}
|
| 4584 |
stride = {19, 4, 1}
|
| 4585 |
```
|
| 4586 |
|
| 4587 |
yields the sequence of one-dimensional indices
|
| 4588 |
-
|
| 4589 |
$$k = 3 + (0, 1) \times 19 + (0, 1, 2, 3) \times 4 + (0, 1, 2) \times 1$$
|
| 4590 |
-
|
| 4591 |
which are ordered as shown in the following table:
|
| 4592 |
|
| 4593 |
That is, the highest-ordered index turns fastest.
|
| 4594 |
|
|
|
|
|
|
|
| 4595 |
It is possible to have degenerate generalized slices in which an address
|
| 4596 |
is repeated.
|
| 4597 |
|
|
|
|
|
|
|
| 4598 |
If the stride parameters in the previous example are changed to {1, 1,
|
| 4599 |
1}, the first few elements of the resulting sequence of indices will be
|
| 4600 |
|
|
|
|
|
|
|
| 4601 |
If a degenerate slice is used as the argument to the non-`const` version
|
| 4602 |
-
of `operator[](const gslice&)`, the
|
| 4603 |
|
| 4604 |
#### `gslice` constructors <a id="gslice.cons">[[gslice.cons]]</a>
|
| 4605 |
|
| 4606 |
``` cpp
|
| 4607 |
gslice();
|
|
@@ -4635,11 +4740,11 @@ linear in the number of strides.
|
|
| 4635 |
|
| 4636 |
``` cpp
|
| 4637 |
namespace std {
|
| 4638 |
template <class T> class gslice_array {
|
| 4639 |
public:
|
| 4640 |
-
|
| 4641 |
|
| 4642 |
void operator= (const valarray<T>&) const;
|
| 4643 |
void operator*= (const valarray<T>&) const;
|
| 4644 |
void operator/= (const valarray<T>&) const;
|
| 4645 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4684,11 +4789,11 @@ const gslice_array& operator=(const gslice_array&) const;
|
|
| 4684 |
|
| 4685 |
These assignment operators have reference semantics, assigning the
|
| 4686 |
values of the argument array elements to selected elements of the
|
| 4687 |
`valarray<T>` object to which the `gslice_array` refers.
|
| 4688 |
|
| 4689 |
-
#### `gslice_array` <a id="gslice.array.comp.assign">[[gslice.array.comp.assign]]</a>
|
| 4690 |
|
| 4691 |
``` cpp
|
| 4692 |
void operator*= (const valarray<T>&) const;
|
| 4693 |
void operator/= (const valarray<T>&) const;
|
| 4694 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4699,11 +4804,11 @@ void operator&= (const valarray<T>&) const;
|
|
| 4699 |
void operator|= (const valarray<T>&) const;
|
| 4700 |
void operator<<=(const valarray<T>&) const;
|
| 4701 |
void operator>>=(const valarray<T>&) const;
|
| 4702 |
```
|
| 4703 |
|
| 4704 |
-
These
|
| 4705 |
indicated operation to the elements of the argument array and selected
|
| 4706 |
elements of the `valarray<T>` object to which the `gslice_array` object
|
| 4707 |
refers.
|
| 4708 |
|
| 4709 |
#### `gslice_array` fill function <a id="gslice.array.fill">[[gslice.array.fill]]</a>
|
|
@@ -4722,11 +4827,11 @@ argument to the elements of the `valarray<T>` object to which the
|
|
| 4722 |
|
| 4723 |
``` cpp
|
| 4724 |
namespace std {
|
| 4725 |
template <class T> class mask_array {
|
| 4726 |
public:
|
| 4727 |
-
|
| 4728 |
|
| 4729 |
void operator= (const valarray<T>&) const;
|
| 4730 |
void operator*= (const valarray<T>&) const;
|
| 4731 |
void operator/= (const valarray<T>&) const;
|
| 4732 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4768,11 +4873,11 @@ const mask_array& operator=(const mask_array&) const;
|
|
| 4768 |
|
| 4769 |
These assignment operators have reference semantics, assigning the
|
| 4770 |
values of the argument array elements to selected elements of the
|
| 4771 |
`valarray<T>` object to which it refers.
|
| 4772 |
|
| 4773 |
-
#### `mask_array`
|
| 4774 |
|
| 4775 |
``` cpp
|
| 4776 |
void operator*= (const valarray<T>&) const;
|
| 4777 |
void operator/= (const valarray<T>&) const;
|
| 4778 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4783,11 +4888,11 @@ void operator&= (const valarray<T>&) const;
|
|
| 4783 |
void operator|= (const valarray<T>&) const;
|
| 4784 |
void operator<<=(const valarray<T>&) const;
|
| 4785 |
void operator>>=(const valarray<T>&) const;
|
| 4786 |
```
|
| 4787 |
|
| 4788 |
-
These
|
| 4789 |
indicated operation to the elements of the argument array and selected
|
| 4790 |
elements of the `valarray<T>` object to which the mask object refers.
|
| 4791 |
|
| 4792 |
#### `mask_array` fill function <a id="mask.array.fill">[[mask.array.fill]]</a>
|
| 4793 |
|
|
@@ -4805,11 +4910,11 @@ argument to the elements of the `valarray<T>` object to which the
|
|
| 4805 |
|
| 4806 |
``` cpp
|
| 4807 |
namespace std {
|
| 4808 |
template <class T> class indirect_array {
|
| 4809 |
public:
|
| 4810 |
-
|
| 4811 |
|
| 4812 |
void operator= (const valarray<T>&) const;
|
| 4813 |
void operator*= (const valarray<T>&) const;
|
| 4814 |
void operator/= (const valarray<T>&) const;
|
| 4815 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4855,21 +4960,25 @@ values of the argument array elements to selected elements of the
|
|
| 4855 |
`valarray<T>` object to which it refers.
|
| 4856 |
|
| 4857 |
If the `indirect_array` specifies an element in the `valarray<T>` object
|
| 4858 |
to which it refers more than once, the behavior is undefined.
|
| 4859 |
|
|
|
|
|
|
|
| 4860 |
``` cpp
|
| 4861 |
int addr[] = {2, 3, 1, 4, 4};
|
| 4862 |
valarray<size_t> indirect(addr, 5);
|
| 4863 |
valarray<double> a(0., 10), b(1., 5);
|
| 4864 |
a[indirect] = b;
|
| 4865 |
```
|
| 4866 |
|
| 4867 |
results in undefined behavior since element 4 is specified twice in the
|
| 4868 |
indirection.
|
| 4869 |
|
| 4870 |
-
|
|
|
|
|
|
|
| 4871 |
|
| 4872 |
``` cpp
|
| 4873 |
void operator*= (const valarray<T>&) const;
|
| 4874 |
void operator/= (const valarray<T>&) const;
|
| 4875 |
void operator%= (const valarray<T>&) const;
|
|
@@ -4880,11 +4989,11 @@ void operator&= (const valarray<T>&) const;
|
|
| 4880 |
void operator|= (const valarray<T>&) const;
|
| 4881 |
void operator<<=(const valarray<T>&) const;
|
| 4882 |
void operator>>=(const valarray<T>&) const;
|
| 4883 |
```
|
| 4884 |
|
| 4885 |
-
These
|
| 4886 |
indicated operation to the elements of the argument array and selected
|
| 4887 |
elements of the `valarray<T>` object to which the `indirect_array`
|
| 4888 |
object refers.
|
| 4889 |
|
| 4890 |
If the `indirect_array` specifies an element in the `valarray<T>` object
|
|
@@ -4898,19 +5007,21 @@ void operator=(const T&) const;
|
|
| 4898 |
|
| 4899 |
This function has reference semantics, assigning the value of its
|
| 4900 |
argument to the elements of the `valarray<T>` object to which the
|
| 4901 |
`indirect_array` object refers.
|
| 4902 |
|
| 4903 |
-
### valarray range access <a id="valarray.range">[[valarray.range]]</a>
|
| 4904 |
|
| 4905 |
In the `begin` and `end` function templates that follow, *unspecified*1
|
| 4906 |
is a type that meets the requirements of a mutable random access
|
| 4907 |
-
iterator ([[random.access.iterators]])
|
| 4908 |
-
|
| 4909 |
-
|
| 4910 |
-
random access iterator (
|
| 4911 |
-
|
|
|
|
|
|
|
| 4912 |
|
| 4913 |
The iterators returned by `begin` and `end` for an array are guaranteed
|
| 4914 |
to be valid until the member function `resize(size_t, T)` (
|
| 4915 |
[[valarray.members]]) is called for that array or until the lifetime of
|
| 4916 |
that array ends, whichever happens first.
|
|
@@ -4918,93 +5029,365 @@ that array ends, whichever happens first.
|
|
| 4918 |
``` cpp
|
| 4919 |
template <class T> unspecified{1} begin(valarray<T>& v);
|
| 4920 |
template <class T> unspecified{2} begin(const valarray<T>& v);
|
| 4921 |
```
|
| 4922 |
|
| 4923 |
-
*Returns:* An iterator referencing the first value in the
|
| 4924 |
|
| 4925 |
``` cpp
|
| 4926 |
template <class T> unspecified{1} end(valarray<T>& v);
|
| 4927 |
template <class T> unspecified{2} end(const valarray<T>& v);
|
| 4928 |
```
|
| 4929 |
|
| 4930 |
-
*Returns:* An iterator referencing one past the last value in the
|
| 4931 |
-
numeric array.
|
| 4932 |
|
| 4933 |
## Generalized numeric operations <a id="numeric.ops">[[numeric.ops]]</a>
|
| 4934 |
|
| 4935 |
### Header `<numeric>` synopsis <a id="numeric.ops.overview">[[numeric.ops.overview]]</a>
|
| 4936 |
|
| 4937 |
``` cpp
|
| 4938 |
namespace std {
|
|
|
|
| 4939 |
template <class InputIterator, class T>
|
| 4940 |
T accumulate(InputIterator first, InputIterator last, T init);
|
| 4941 |
template <class InputIterator, class T, class BinaryOperation>
|
| 4942 |
T accumulate(InputIterator first, InputIterator last, T init,
|
| 4943 |
BinaryOperation binary_op);
|
| 4944 |
|
|
|
|
|
|
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|
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|
|
|
|
| 4945 |
template <class InputIterator1, class InputIterator2, class T>
|
| 4946 |
T inner_product(InputIterator1 first1, InputIterator1 last1,
|
| 4947 |
InputIterator2 first2, T init);
|
| 4948 |
template <class InputIterator1, class InputIterator2, class T,
|
| 4949 |
class BinaryOperation1, class BinaryOperation2>
|
| 4950 |
T inner_product(InputIterator1 first1, InputIterator1 last1,
|
| 4951 |
InputIterator2 first2, T init,
|
| 4952 |
BinaryOperation1 binary_op1,
|
| 4953 |
BinaryOperation2 binary_op2);
|
| 4954 |
|
|
|
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|
|
|
|
|
|
| 4955 |
template <class InputIterator, class OutputIterator>
|
| 4956 |
OutputIterator partial_sum(InputIterator first,
|
| 4957 |
InputIterator last,
|
| 4958 |
OutputIterator result);
|
| 4959 |
-
template <class InputIterator, class OutputIterator,
|
| 4960 |
-
class BinaryOperation>
|
| 4961 |
OutputIterator partial_sum(InputIterator first,
|
| 4962 |
InputIterator last,
|
| 4963 |
OutputIterator result,
|
| 4964 |
BinaryOperation binary_op);
|
| 4965 |
|
|
|
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|
|
|
| 4966 |
template <class InputIterator, class OutputIterator>
|
| 4967 |
OutputIterator adjacent_difference(InputIterator first,
|
| 4968 |
InputIterator last,
|
| 4969 |
OutputIterator result);
|
| 4970 |
-
template <class InputIterator, class OutputIterator,
|
| 4971 |
-
class BinaryOperation>
|
| 4972 |
OutputIterator adjacent_difference(InputIterator first,
|
| 4973 |
InputIterator last,
|
| 4974 |
OutputIterator result,
|
| 4975 |
BinaryOperation binary_op);
|
|
|
|
|
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|
|
|
|
|
|
| 4976 |
|
|
|
|
| 4977 |
template <class ForwardIterator, class T>
|
| 4978 |
void iota(ForwardIterator first, ForwardIterator last, T value);
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
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|
|
|
|
|
|
|
| 4979 |
}
|
| 4980 |
```
|
| 4981 |
|
| 4982 |
The requirements on the types of algorithms’ arguments that are
|
| 4983 |
described in the introduction to Clause [[algorithms]] also apply to
|
| 4984 |
the following algorithms.
|
| 4985 |
|
|
|
|
|
|
|
|
|
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|
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|
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|
|
|
|
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|
|
|
|
|
|
| 4986 |
### Accumulate <a id="accumulate">[[accumulate]]</a>
|
| 4987 |
|
| 4988 |
``` cpp
|
| 4989 |
template <class InputIterator, class T>
|
| 4990 |
T accumulate(InputIterator first, InputIterator last, T init);
|
| 4991 |
template <class InputIterator, class T, class BinaryOperation>
|
| 4992 |
T accumulate(InputIterator first, InputIterator last, T init,
|
| 4993 |
BinaryOperation binary_op);
|
| 4994 |
```
|
| 4995 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4996 |
*Effects:* Computes its result by initializing the accumulator `acc`
|
| 4997 |
with the initial value `init` and then modifies it with `acc = acc + *i`
|
| 4998 |
or `acc = binary_op(acc, *i)` for every iterator `i` in the range
|
| 4999 |
-
\[`first`, `last`) in order.[^
|
| 5000 |
|
| 5001 |
-
|
| 5002 |
-
|
| 5003 |
-
|
| 5004 |
-
|
| 5005 |
-
|
|
|
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|
|
|
| 5006 |
|
| 5007 |
### Inner product <a id="inner.product">[[inner.product]]</a>
|
| 5008 |
|
| 5009 |
``` cpp
|
| 5010 |
template <class InputIterator1, class InputIterator2, class T>
|
|
@@ -5016,98 +5399,532 @@ template <class InputIterator1, class InputIterator2, class T,
|
|
| 5016 |
InputIterator2 first2, T init,
|
| 5017 |
BinaryOperation1 binary_op1,
|
| 5018 |
BinaryOperation2 binary_op2);
|
| 5019 |
```
|
| 5020 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5021 |
*Effects:* Computes its result by initializing the accumulator `acc`
|
| 5022 |
with the initial value `init` and then modifying it with
|
| 5023 |
`acc = acc + (*i1) * (*i2)` or
|
| 5024 |
`acc = binary_op1(acc, binary_op2(*i1, *i2))` for every iterator `i1` in
|
| 5025 |
the range \[`first1`, `last1`) and iterator `i2` in the range
|
| 5026 |
\[`first2`, `first2 + (last1 - first1)`) in order.
|
| 5027 |
|
| 5028 |
-
|
| 5029 |
-
|
| 5030 |
-
|
| 5031 |
-
|
| 5032 |
-
|
| 5033 |
-
|
|
|
|
|
|
|
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|
|
|
|
| 5034 |
|
| 5035 |
### Partial sum <a id="partial.sum">[[partial.sum]]</a>
|
| 5036 |
|
| 5037 |
``` cpp
|
| 5038 |
template <class InputIterator, class OutputIterator>
|
| 5039 |
OutputIterator partial_sum(
|
| 5040 |
InputIterator first, InputIterator last,
|
| 5041 |
OutputIterator result);
|
| 5042 |
-
template
|
| 5043 |
-
<class InputIterator, class OutputIterator, class BinaryOperation>
|
| 5044 |
OutputIterator partial_sum(
|
| 5045 |
InputIterator first, InputIterator last,
|
| 5046 |
OutputIterator result, BinaryOperation binary_op);
|
| 5047 |
```
|
| 5048 |
|
| 5049 |
-
*Effects:* For a non-empty range, the function creates an accumulator
|
| 5050 |
-
`acc` whose type is `InputIterator`’s value type, initializes it with
|
| 5051 |
-
`*first`, and assigns the result to `*result`. For every iterator `i` in
|
| 5052 |
-
\[`first + 1`, `last`) in order, `acc` is then modified by
|
| 5053 |
-
`acc = acc + *i` or `acc = binary_op(acc, *i)` and the result is
|
| 5054 |
-
assigned to `*(result + (i - first))`.
|
| 5055 |
-
|
| 5056 |
-
*Returns:* `result + (last - first)`.
|
| 5057 |
-
|
| 5058 |
-
*Complexity:* Exactly `(last - first) - 1` applications of the binary
|
| 5059 |
-
operation.
|
| 5060 |
-
|
| 5061 |
*Requires:* `InputIterator`’s value type shall be constructible from the
|
| 5062 |
type of `*first`. The result of the expression `acc + *i` or
|
| 5063 |
`binary_op(acc, *i)` shall be implicitly convertible to
|
| 5064 |
-
`InputIterator`’s value type. `acc` shall be
|
| 5065 |
-
|
| 5066 |
-
|
| 5067 |
-
|
| 5068 |
-
subranges.[^
|
|
|
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|
| 5069 |
|
| 5070 |
*Remarks:* `result` may be equal to `first`.
|
| 5071 |
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|
| 5072 |
### Adjacent difference <a id="adjacent.difference">[[adjacent.difference]]</a>
|
| 5073 |
|
| 5074 |
``` cpp
|
| 5075 |
template <class InputIterator, class OutputIterator>
|
| 5076 |
-
OutputIterator
|
| 5077 |
-
InputIterator first, InputIterator last,
|
| 5078 |
OutputIterator result);
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5079 |
template <class InputIterator, class OutputIterator, class BinaryOperation>
|
| 5080 |
-
OutputIterator
|
| 5081 |
-
InputIterator first, InputIterator last,
|
| 5082 |
OutputIterator result,
|
| 5083 |
BinaryOperation binary_op);
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5084 |
```
|
| 5085 |
|
| 5086 |
-
*
|
| 5087 |
-
|
| 5088 |
-
|
| 5089 |
-
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5090 |
`InputIterator`’s value type, initializes it with `*i`, computes
|
| 5091 |
`val - acc` or `binary_op(val, acc)`, assigns the result to
|
| 5092 |
`*(result + (i - first))`, and move assigns from `val` to `acc`.
|
| 5093 |
|
| 5094 |
-
|
| 5095 |
-
|
| 5096 |
-
`*first`
|
| 5097 |
-
|
| 5098 |
-
|
| 5099 |
-
`
|
| 5100 |
-
|
| 5101 |
-
|
| 5102 |
-
*Remarks:* `result` may be equal to `first`.
|
| 5103 |
|
| 5104 |
*Returns:* `result + (last - first)`.
|
| 5105 |
|
| 5106 |
*Complexity:* Exactly `(last - first) - 1` applications of the binary
|
| 5107 |
operation.
|
| 5108 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5109 |
### Iota <a id="numeric.iota">[[numeric.iota]]</a>
|
| 5110 |
|
| 5111 |
``` cpp
|
| 5112 |
template <class ForwardIterator, class T>
|
| 5113 |
void iota(ForwardIterator first, ForwardIterator last, T value);
|
|
@@ -5120,252 +5937,1181 @@ The expression `++val`, where `val` has type `T`, shall be well formed.
|
|
| 5120 |
\[`first`, `last`), assigns `*i = value` and increments `value` as if by
|
| 5121 |
`++value`.
|
| 5122 |
|
| 5123 |
*Complexity:* Exactly `last - first` increments and assignments.
|
| 5124 |
|
| 5125 |
-
##
|
| 5126 |
|
| 5127 |
-
|
| 5128 |
-
|
|
|
|
|
|
|
| 5129 |
|
| 5130 |
-
|
| 5131 |
-
|
| 5132 |
|
| 5133 |
-
|
| 5134 |
-
|
|
|
|
| 5135 |
|
| 5136 |
-
|
| 5137 |
-
|
| 5138 |
-
changes:
|
| 5139 |
|
| 5140 |
-
|
| 5141 |
-
|
| 5142 |
-
functions may call `rand`. It is implementation-defined whether the
|
| 5143 |
-
`rand` function may introduce data races ([[res.on.data.races]]). The
|
| 5144 |
-
random number generation ([[rand]]) facilities in this standard are
|
| 5145 |
-
often preferable to `rand`, because `rand`’s underlying algorithm is
|
| 5146 |
-
unspecified. Use of `rand` therefore continues to be nonportable, with
|
| 5147 |
-
unpredictable and oft-questionable quality and performance.
|
| 5148 |
|
| 5149 |
-
|
| 5150 |
-
`<cstdlib>`, C++adds `long` and `long long` overloaded versions of these
|
| 5151 |
-
functions, with the same semantics.
|
| 5152 |
|
| 5153 |
-
|
| 5154 |
|
| 5155 |
``` cpp
|
| 5156 |
-
|
| 5157 |
-
|
| 5158 |
-
ldiv_t div(long, long); // ldiv()
|
| 5159 |
-
lldiv_t div(long long, long long); // lldiv()
|
| 5160 |
```
|
| 5161 |
|
| 5162 |
-
|
| 5163 |
-
|
| 5164 |
-
|
| 5165 |
|
| 5166 |
-
|
|
|
|
| 5167 |
|
| 5168 |
-
```
|
| 5169 |
-
|
| 5170 |
-
|
| 5171 |
-
|
| 5172 |
-
float asin(float);
|
| 5173 |
-
float asinh(float);
|
| 5174 |
-
float atan(float);
|
| 5175 |
-
float atan2(float, float);
|
| 5176 |
-
float atanh(float);
|
| 5177 |
-
float cbrt(float);
|
| 5178 |
-
float ceil(float);
|
| 5179 |
-
float copysign(float, float);
|
| 5180 |
-
float cos(float);
|
| 5181 |
-
float cosh(float);
|
| 5182 |
-
float erf(float);
|
| 5183 |
-
float erfc(float);
|
| 5184 |
-
float exp(float);
|
| 5185 |
-
float exp2(float);
|
| 5186 |
-
float expm1(float);
|
| 5187 |
-
float fabs(float);
|
| 5188 |
-
float fdim(float, float);
|
| 5189 |
-
float floor(float);
|
| 5190 |
-
float fma(float, float, float);
|
| 5191 |
-
float fmax(float, float);
|
| 5192 |
-
float fmin(float, float);
|
| 5193 |
-
float fmod(float, float);
|
| 5194 |
-
float frexp(float, int*);
|
| 5195 |
-
float hypot(float, float);
|
| 5196 |
-
int ilogb(float);
|
| 5197 |
-
float ldexp(float, int);
|
| 5198 |
-
float lgamma(float);
|
| 5199 |
-
long long llrint(float);
|
| 5200 |
-
long long llround(float);
|
| 5201 |
-
float log(float);
|
| 5202 |
-
float log10(float);
|
| 5203 |
-
float log1p(float);
|
| 5204 |
-
float log2(float);
|
| 5205 |
-
float logb(float);
|
| 5206 |
-
long lrint(float);
|
| 5207 |
-
long lround(float);
|
| 5208 |
-
float modf(float, float*);
|
| 5209 |
-
float nearbyint(float);
|
| 5210 |
-
float nextafter(float, float);
|
| 5211 |
-
float nexttoward(float, long double);
|
| 5212 |
-
float pow(float, float);
|
| 5213 |
-
float remainder(float, float);
|
| 5214 |
-
float remquo(float, float, int *);
|
| 5215 |
-
float rint(float);
|
| 5216 |
-
float round(float);
|
| 5217 |
-
float scalbln(float, long);
|
| 5218 |
-
float scalbn(float, int);
|
| 5219 |
-
float sin(float);
|
| 5220 |
-
float sinh(float);
|
| 5221 |
-
float sqrt(float);
|
| 5222 |
-
float tan(float);
|
| 5223 |
-
float tanh(float);
|
| 5224 |
-
float tgamma(float);
|
| 5225 |
-
float trunc(float);
|
| 5226 |
-
|
| 5227 |
-
double abs(double); // fabs()
|
| 5228 |
-
|
| 5229 |
-
long double abs(long double);
|
| 5230 |
-
long double acos(long double);
|
| 5231 |
-
long double acosh(long double);
|
| 5232 |
-
long double asin(long double);
|
| 5233 |
-
long double asinh(long double);
|
| 5234 |
-
long double atan(long double);
|
| 5235 |
-
long double atan2(long double, long double);
|
| 5236 |
-
long double atanh(long double);
|
| 5237 |
-
long double cbrt(long double);
|
| 5238 |
-
long double ceil(long double);
|
| 5239 |
-
long double copysign(long double, long double);
|
| 5240 |
-
long double cos(long double);
|
| 5241 |
-
long double cosh(long double);
|
| 5242 |
-
long double erf(long double);
|
| 5243 |
-
long double erfc(long double);
|
| 5244 |
-
long double exp(long double);
|
| 5245 |
-
long double exp2(long double);
|
| 5246 |
-
long double expm1(long double);
|
| 5247 |
-
long double fabs(long double);
|
| 5248 |
-
long double fdim(long double, long double);
|
| 5249 |
-
long double floor(long double);
|
| 5250 |
-
long double fma(long double, long double, long double);
|
| 5251 |
-
long double fmax(long double, long double);
|
| 5252 |
-
long double fmin(long double, long double);
|
| 5253 |
-
long double fmod(long double, long double);
|
| 5254 |
-
long double frexp(long double, int*);
|
| 5255 |
-
long double hypot(long double, long double);
|
| 5256 |
-
int ilogb(long double);
|
| 5257 |
-
long double ldexp(long double, int);
|
| 5258 |
-
long double lgamma(long double);
|
| 5259 |
-
long long llrint(long double);
|
| 5260 |
-
long long llround(long double);
|
| 5261 |
-
long double log(long double);
|
| 5262 |
-
long double log10(long double);
|
| 5263 |
-
long double log1p(long double);
|
| 5264 |
-
long double log2(long double);
|
| 5265 |
-
long double logb(long double);
|
| 5266 |
-
long lrint(long double);
|
| 5267 |
-
long lround(long double);
|
| 5268 |
-
long double modf(long double, long double*);
|
| 5269 |
-
long double nearbyint(long double);
|
| 5270 |
-
long double nextafter(long double, long double);
|
| 5271 |
-
long double nexttoward(long double, long double);
|
| 5272 |
-
long double pow(long double, long double);
|
| 5273 |
-
long double remainder(long double, long double);
|
| 5274 |
-
long double remquo(long double, long double, int *);
|
| 5275 |
-
long double rint(long double);
|
| 5276 |
-
long double round(long double);
|
| 5277 |
-
long double scalbln(long double, long);
|
| 5278 |
-
long double scalbn(long double, int);
|
| 5279 |
-
long double sin(long double);
|
| 5280 |
-
long double sinh(long double);
|
| 5281 |
-
long double sqrt(long double);
|
| 5282 |
-
long double tan(long double);
|
| 5283 |
-
long double tanh(long double);
|
| 5284 |
-
long double tgamma(long double);
|
| 5285 |
-
long double trunc(long double);
|
| 5286 |
-
```
|
| 5287 |
|
| 5288 |
-
|
| 5289 |
-
|
| 5290 |
-
|
| 5291 |
-
overloaded for the three floating-point types, as follows:
|
| 5292 |
|
| 5293 |
``` cpp
|
|
|
|
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|
| 5294 |
int fpclassify(float x);
|
| 5295 |
-
bool isfinite(float x);
|
| 5296 |
-
bool isinf(float x);
|
| 5297 |
-
bool isnan(float x);
|
| 5298 |
-
bool isnormal(float x);
|
| 5299 |
-
bool signbit(float x);
|
| 5300 |
-
|
| 5301 |
-
bool isgreater(float x, float y);
|
| 5302 |
-
bool isgreaterequal(float x, float y);
|
| 5303 |
-
bool isless(float x, float y);
|
| 5304 |
-
bool islessequal(float x, float y);
|
| 5305 |
-
bool islessgreater(float x, float y);
|
| 5306 |
-
bool isunordered(float x, float y);
|
| 5307 |
-
|
| 5308 |
int fpclassify(double x);
|
| 5309 |
-
bool isfinite(double x);
|
| 5310 |
-
bool isinf(double x);
|
| 5311 |
-
bool isnan(double x);
|
| 5312 |
-
bool isnormal(double x);
|
| 5313 |
-
bool signbit(double x);
|
| 5314 |
-
|
| 5315 |
-
bool isgreater(double x, double y);
|
| 5316 |
-
bool isgreaterequal(double x, double y);
|
| 5317 |
-
bool isless(double x, double y);
|
| 5318 |
-
bool islessequal(double x, double y);
|
| 5319 |
-
bool islessgreater(double x, double y);
|
| 5320 |
-
bool isunordered(double x, double y);
|
| 5321 |
-
|
| 5322 |
int fpclassify(long double x);
|
| 5323 |
-
|
| 5324 |
-
|
| 5325 |
-
|
| 5326 |
-
|
| 5327 |
-
|
| 5328 |
-
|
| 5329 |
-
|
| 5330 |
-
|
| 5331 |
-
|
| 5332 |
-
|
| 5333 |
-
|
| 5334 |
-
|
| 5335 |
-
|
| 5336 |
-
|
| 5337 |
-
|
| 5338 |
-
|
| 5339 |
-
|
| 5340 |
-
|
| 5341 |
-
|
| 5342 |
-
|
| 5343 |
-
|
| 5344 |
-
|
| 5345 |
-
|
| 5346 |
-
|
| 5347 |
-
|
| 5348 |
-
|
| 5349 |
-
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| 5350 |
|
| 5351 |
<!-- Link reference definitions -->
|
| 5352 |
[accumulate]: #accumulate
|
| 5353 |
[adjacent.difference]: #adjacent.difference
|
| 5354 |
[algorithms]: algorithms.md#algorithms
|
| 5355 |
[bad.alloc]: language.md#bad.alloc
|
| 5356 |
[basic.fundamental]: basic.md#basic.fundamental
|
| 5357 |
[basic.stc.thread]: basic.md#basic.stc.thread
|
| 5358 |
[basic.types]: basic.md#basic.types
|
| 5359 |
[c.math]: #c.math
|
| 5360 |
-
[
|
|
|
|
|
|
|
|
|
|
| 5361 |
[cfenv]: #cfenv
|
| 5362 |
[cfenv.syn]: #cfenv.syn
|
| 5363 |
[class.gslice]: #class.gslice
|
| 5364 |
[class.gslice.overview]: #class.gslice.overview
|
| 5365 |
[class.slice]: #class.slice
|
| 5366 |
[class.slice.overview]: #class.slice.overview
|
|
|
|
| 5367 |
[cmplx.over]: #cmplx.over
|
| 5368 |
[complex]: #complex
|
| 5369 |
[complex.literals]: #complex.literals
|
| 5370 |
[complex.member.ops]: #complex.member.ops
|
| 5371 |
[complex.members]: #complex.members
|
|
@@ -5374,39 +7120,48 @@ ISO C 7.5, 7.10.2, 7.10.6.
|
|
| 5374 |
[complex.special]: #complex.special
|
| 5375 |
[complex.syn]: #complex.syn
|
| 5376 |
[complex.transcendentals]: #complex.transcendentals
|
| 5377 |
[complex.value.ops]: #complex.value.ops
|
| 5378 |
[cons.slice]: #cons.slice
|
| 5379 |
-
[
|
| 5380 |
-
[
|
|
|
|
|
|
|
| 5381 |
[dcl.init]: dcl.md#dcl.init
|
| 5382 |
-
[
|
| 5383 |
[function.objects]: utilities.md#function.objects
|
| 5384 |
[gslice.access]: #gslice.access
|
| 5385 |
[gslice.array.assign]: #gslice.array.assign
|
| 5386 |
[gslice.array.comp.assign]: #gslice.array.comp.assign
|
| 5387 |
[gslice.array.fill]: #gslice.array.fill
|
| 5388 |
[gslice.cons]: #gslice.cons
|
|
|
|
|
|
|
| 5389 |
[indirect.array.assign]: #indirect.array.assign
|
| 5390 |
[indirect.array.comp.assign]: #indirect.array.comp.assign
|
| 5391 |
[indirect.array.fill]: #indirect.array.fill
|
| 5392 |
[inner.product]: #inner.product
|
|
|
|
| 5393 |
[input.output]: input.md#input.output
|
| 5394 |
[iostate.flags]: input.md#iostate.flags
|
| 5395 |
[istream.formatted]: input.md#istream.formatted
|
| 5396 |
-
[
|
|
|
|
| 5397 |
[mask.array.assign]: #mask.array.assign
|
| 5398 |
[mask.array.comp.assign]: #mask.array.comp.assign
|
| 5399 |
[mask.array.fill]: #mask.array.fill
|
| 5400 |
-
[moveassignable]: #moveassignable
|
| 5401 |
[numarray]: #numarray
|
| 5402 |
[numeric.iota]: #numeric.iota
|
| 5403 |
[numeric.ops]: #numeric.ops
|
|
|
|
|
|
|
| 5404 |
[numeric.ops.overview]: #numeric.ops.overview
|
| 5405 |
[numeric.requirements]: #numeric.requirements
|
| 5406 |
[numerics]: #numerics
|
|
|
|
| 5407 |
[numerics.general]: #numerics.general
|
|
|
|
| 5408 |
[partial.sum]: #partial.sum
|
| 5409 |
[rand]: #rand
|
| 5410 |
[rand.adapt]: #rand.adapt
|
| 5411 |
[rand.adapt.disc]: #rand.adapt.disc
|
| 5412 |
[rand.adapt.general]: #rand.adapt.general
|
|
@@ -5455,25 +7210,49 @@ ISO C 7.5, 7.10.2, 7.10.6.
|
|
| 5455 |
[rand.synopsis]: #rand.synopsis
|
| 5456 |
[rand.util]: #rand.util
|
| 5457 |
[rand.util.canonical]: #rand.util.canonical
|
| 5458 |
[rand.util.seedseq]: #rand.util.seedseq
|
| 5459 |
[random.access.iterators]: iterators.md#random.access.iterators
|
|
|
|
| 5460 |
[res.on.data.races]: library.md#res.on.data.races
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5461 |
[slice.access]: #slice.access
|
| 5462 |
[slice.arr.assign]: #slice.arr.assign
|
| 5463 |
[slice.arr.comp.assign]: #slice.arr.comp.assign
|
| 5464 |
[slice.arr.fill]: #slice.arr.fill
|
| 5465 |
[strings]: strings.md#strings
|
| 5466 |
[tab:RandomDistribution]: #tab:RandomDistribution
|
| 5467 |
[tab:RandomEngine]: #tab:RandomEngine
|
| 5468 |
[tab:SeedSequence]: #tab:SeedSequence
|
| 5469 |
-
[tab:
|
|
|
|
|
|
|
|
|
|
| 5470 |
[tab:iterator.input.requirements]: iterators.md#tab:iterator.input.requirements
|
| 5471 |
-
[tab:
|
| 5472 |
-
[tab:
|
| 5473 |
-
[tab:numerics.hdr.cmath]: #tab:numerics.hdr.cmath
|
| 5474 |
-
[tab:numerics.hdr.cstdlib]: #tab:numerics.hdr.cstdlib
|
| 5475 |
[tab:numerics.lib.summary]: #tab:numerics.lib.summary
|
| 5476 |
[template.gslice.array]: #template.gslice.array
|
| 5477 |
[template.gslice.array.overview]: #template.gslice.array.overview
|
| 5478 |
[template.indirect.array]: #template.indirect.array
|
| 5479 |
[template.indirect.array.overview]: #template.indirect.array.overview
|
|
@@ -5482,10 +7261,13 @@ ISO C 7.5, 7.10.2, 7.10.6.
|
|
| 5482 |
[template.slice.array]: #template.slice.array
|
| 5483 |
[template.slice.array.overview]: #template.slice.array.overview
|
| 5484 |
[template.valarray]: #template.valarray
|
| 5485 |
[template.valarray.overview]: #template.valarray.overview
|
| 5486 |
[thread.thread.class]: thread.md#thread.thread.class
|
|
|
|
|
|
|
|
|
|
| 5487 |
[valarray.access]: #valarray.access
|
| 5488 |
[valarray.assign]: #valarray.assign
|
| 5489 |
[valarray.binary]: #valarray.binary
|
| 5490 |
[valarray.cassign]: #valarray.cassign
|
| 5491 |
[valarray.comparison]: #valarray.comparison
|
|
@@ -5521,53 +7303,51 @@ ISO C 7.5, 7.10.2, 7.10.6.
|
|
| 5521 |
[^6]: The distribution corresponding to this probability density
|
| 5522 |
function is also known (with a possible change of variable) as the
|
| 5523 |
Gumbel Type I, the log-Weibull, or the Fisher-Tippett Type I
|
| 5524 |
distribution.
|
| 5525 |
|
| 5526 |
-
[^7]:
|
| 5527 |
nested template instantiations. This requirement thus indirectly
|
| 5528 |
suggests a minimum allowable complexity for valarray expressions.
|
| 5529 |
|
| 5530 |
[^8]: The intent is to specify an array template that has the minimum
|
| 5531 |
functionality necessary to address aliasing ambiguities and the
|
| 5532 |
proliferation of temporaries. Thus, the `valarray` template is
|
| 5533 |
neither a matrix class nor a field class. However, it is a very
|
| 5534 |
useful building block for designing such classes.
|
| 5535 |
|
| 5536 |
-
[^9]:
|
| 5537 |
-
throughout the remainder of [[numarray]].
|
| 5538 |
-
|
| 5539 |
-
[^10]: This default constructor is essential, since arrays of `valarray`
|
| 5540 |
may be useful. After initialization, the length of an empty array
|
| 5541 |
can be increased with the `resize` member function.
|
| 5542 |
|
| 5543 |
-
[^
|
| 5544 |
to a `valarray` object.
|
| 5545 |
|
| 5546 |
-
[^
|
| 5547 |
alias. Implementations in which arrays share storage are permitted,
|
| 5548 |
but they shall implement a copy-on-reference mechanism to ensure
|
| 5549 |
that arrays are conceptually distinct.
|
| 5550 |
|
| 5551 |
-
[^
|
| 5552 |
-
loop fusion, tracking of pointers obtained from `operator new`, and
|
| 5553 |
-
other techniques to generate efficient `valarray`s.
|
| 5554 |
-
|
| 5555 |
-
[^14]: BLAS stands for *Basic Linear Algebra Subprograms.* C++programs
|
| 5556 |
may instantiate this class. See, for example, Dongarra, Du Croz,
|
| 5557 |
Duff, and Hammerling: *A set of Level 3 Basic Linear Algebra
|
| 5558 |
Subprograms*; Technical Report MCS-P1-0888, Argonne National
|
| 5559 |
Laboratory (USA), Mathematics and Computer Science Division, August,
|
| 5560 |
1988.
|
| 5561 |
|
| 5562 |
-
[^
|
|
|
|
|
|
|
| 5563 |
Lisp reduce function, but it avoids the difficulty of defining the
|
| 5564 |
result of reduction on an empty sequence by always requiring an
|
| 5565 |
initial value.
|
| 5566 |
|
| 5567 |
-
[^
|
| 5568 |
|
| 5569 |
-
[^
|
| 5570 |
|
| 5571 |
-
[^
|
| 5572 |
|
| 5573 |
-
[^
|
|
|
|
|
|
|
|
|
|
|
|
| 5 |
This Clause describes components that C++programs may use to perform
|
| 6 |
seminumerical operations.
|
| 7 |
|
| 8 |
The following subclauses describe components for complex number types,
|
| 9 |
random number generation, numeric ( *n*-at-a-time) arrays, generalized
|
| 10 |
+
numeric algorithms, and mathematical functions for floating-point types,
|
| 11 |
+
as summarized in Table [[tab:numerics.lib.summary]].
|
| 12 |
|
| 13 |
**Table: Numerics library summary** <a id="tab:numerics.lib.summary">[tab:numerics.lib.summary]</a>
|
| 14 |
|
| 15 |
| Subclause | | Header |
|
| 16 |
| ------------------------ | ------------------------------ | ------------ |
|
| 17 |
+
| [[numerics.defns]] | Definitions | |
|
| 18 |
| [[numeric.requirements]] | Requirements | |
|
| 19 |
+
| [[cfenv]] | Floating-point environment | `<cfenv>` |
|
| 20 |
+
| [[complex.numbers]] | Complex numbers | `<complex>` |
|
| 21 |
| [[rand]] | Random number generation | `<random>` |
|
| 22 |
| [[numarray]] | Numeric arrays | `<valarray>` |
|
| 23 |
| [[numeric.ops]] | Generalized numeric operations | `<numeric>` |
|
| 24 |
+
| [[c.math]] | Mathematical functions for | `<cmath>` |
|
| 25 |
+
| | floating-point types | `<cstdlib>` |
|
|
|
|
|
|
|
| 26 |
|
| 27 |
|
| 28 |
+
## Definitions <a id="numerics.defns">[[numerics.defns]]</a>
|
| 29 |
+
|
| 30 |
+
Define `GENERALIZED_NONCOMMUTATIVE_SUM(op, a1, ..., aN)` as follows:
|
| 31 |
+
|
| 32 |
+
- `a1` when `N` is `1`, otherwise
|
| 33 |
+
- `op(GENERALIZED_NONCOMMUTATIVE_SUM(op, a1, ..., aK),`
|
| 34 |
+
`\phantom{op(}GENERALIZED_NONCOMMUTATIVE_SUM(op, aM, ..., aN))` for
|
| 35 |
+
any `K` where 1 < K+1 = M ≤ N.
|
| 36 |
+
|
| 37 |
+
Define `GENERALIZED_SUM(op, a1, ..., aN)` as
|
| 38 |
+
`GENERALIZED_NONCOMMUTATIVE_SUM(op, b1, ..., bN)`, where `b1, ..., bN`
|
| 39 |
+
may be any permutation of `a1, ..., aN`.
|
| 40 |
+
|
| 41 |
## Numeric type requirements <a id="numeric.requirements">[[numeric.requirements]]</a>
|
| 42 |
|
| 43 |
The `complex` and `valarray` components are parameterized by the type of
|
| 44 |
information they contain and manipulate. A C++program shall instantiate
|
| 45 |
these components only with a type `T` that satisfies the following
|
|
|
|
| 55 |
- If `T` is a class, it has a public destructor;
|
| 56 |
- If `T` is a class, it has a public assignment operator whose signature
|
| 57 |
is either `T& T::operator=(const T&)` or `T& T::operator=(T)`
|
| 58 |
- If `T` is a class, its assignment operator, copy and default
|
| 59 |
constructors, and destructor shall correspond to each other in the
|
| 60 |
+
following sense:
|
| 61 |
+
- Initialization of raw storage using the copy constructor on the
|
| 62 |
+
value of `T()`, however obtained, is semantically equivalent to
|
| 63 |
+
value-initialization of the same raw storage.
|
| 64 |
+
- Initialization of raw storage using the default constructor,
|
| 65 |
+
followed by assignment, is semantically equivalent to initialization
|
| 66 |
+
of raw storage using the copy constructor.
|
| 67 |
+
- Destruction of an object, followed by initialization of its raw
|
| 68 |
+
storage using the copy constructor, is semantically equivalent to
|
| 69 |
+
assignment to the original object.
|
| 70 |
+
|
| 71 |
+
\[*Note 1*:
|
| 72 |
+
This rule states, in part, that there shall not be any subtle
|
| 73 |
differences in the semantics of initialization versus assignment. This
|
| 74 |
gives an implementation considerable flexibility in how arrays are
|
| 75 |
+
initialized.
|
| 76 |
+
\[*Example 1*:
|
| 77 |
+
An implementation is allowed to initialize a `valarray` by allocating
|
| 78 |
+
storage using the `new` operator (which implies a call to the default
|
| 79 |
+
constructor for each element) and then assigning each element its
|
| 80 |
+
value. Or the implementation can allocate raw storage and use the copy
|
| 81 |
+
constructor to initialize each element.
|
| 82 |
+
— *end example*]
|
| 83 |
+
If the distinction between initialization and assignment is important
|
| 84 |
+
for a class, or if it fails to satisfy any of the other conditions
|
| 85 |
+
listed above, the programmer should use `vector` ([[vector]]) instead
|
| 86 |
+
of `valarray` for that class.
|
| 87 |
+
— *end note*]
|
| 88 |
- If `T` is a class, it does not overload unary `operator&`.
|
| 89 |
|
| 90 |
If any operation on `T` throws an exception the effects are undefined.
|
| 91 |
|
| 92 |
In addition, many member and related functions of `valarray<T>` can be
|
| 93 |
successfully instantiated and will exhibit well-defined behavior if and
|
| 94 |
only if `T` satisfies additional requirements specified for each such
|
| 95 |
member or related function.
|
| 96 |
|
| 97 |
+
[*Example 2*: It is valid to instantiate `valarray<complex>`, but
|
| 98 |
+
`operator>()` will not be successfully instantiated for
|
| 99 |
+
`valarray<complex>` operands, since `complex` does not have any ordering
|
| 100 |
+
operators. — *end example*]
|
| 101 |
|
| 102 |
## The floating-point environment <a id="cfenv">[[cfenv]]</a>
|
| 103 |
|
| 104 |
### Header `<cfenv>` synopsis <a id="cfenv.syn">[[cfenv.syn]]</a>
|
| 105 |
|
| 106 |
``` cpp
|
| 107 |
+
#define FE_ALL_EXCEPT see below
|
| 108 |
+
#define FE_DIVBYZERO see below
|
| 109 |
+
#define FE_INEXACT see below
|
| 110 |
+
#define FE_INVALID see below
|
| 111 |
+
#define FE_OVERFLOW see below
|
| 112 |
+
#define FE_UNDERFLOW see below
|
| 113 |
+
|
| 114 |
+
#define FE_DOWNWARD see below
|
| 115 |
+
#define FE_TONEAREST see below
|
| 116 |
+
#define FE_TOWARDZERO see below
|
| 117 |
+
#define FE_UPWARD see below
|
| 118 |
+
|
| 119 |
+
#define FE_DFL_ENV see below
|
| 120 |
+
|
| 121 |
namespace std {
|
| 122 |
// types
|
| 123 |
+
using fenv_t = object type;
|
| 124 |
+
using fexcept_t = integer type;
|
| 125 |
|
| 126 |
// functions
|
| 127 |
int feclearexcept(int except);
|
| 128 |
int fegetexceptflag(fexcept_t* pflag, int except);
|
| 129 |
int feraiseexcept(int except);
|
| 130 |
int fesetexceptflag(const fexcept_t* pflag, int except);
|
| 131 |
int fetestexcept(int except);
|
| 132 |
|
| 133 |
+
int fegetround();
|
| 134 |
int fesetround(int mode);
|
| 135 |
|
| 136 |
int fegetenv(fenv_t* penv);
|
| 137 |
int feholdexcept(fenv_t* penv);
|
| 138 |
int fesetenv(const fenv_t* penv);
|
| 139 |
int feupdateenv(const fenv_t* penv);
|
| 140 |
}
|
| 141 |
```
|
| 142 |
|
| 143 |
+
The contents and meaning of the header `<cfenv>` are the same as the C
|
| 144 |
+
standard library header `<fenv.h>`.
|
| 145 |
+
|
| 146 |
+
[*Note 1*: This International Standard does not require an
|
| 147 |
+
implementation to support the `FENV_ACCESS` pragma; it is
|
| 148 |
+
*implementation-defined* ([[cpp.pragma]]) whether the pragma is
|
| 149 |
+
supported. As a consequence, it is *implementation-defined* whether
|
| 150 |
+
these functions can be used to test floating-point status flags, set
|
| 151 |
+
floating-point control modes, or run under non-default mode settings. If
|
| 152 |
+
the pragma is used to enable control over the floating-point
|
| 153 |
+
environment, this International Standard does not specify the effect on
|
| 154 |
+
floating-point evaluation in constant expressions. — *end note*]
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 155 |
|
| 156 |
The floating-point environment has thread storage duration (
|
| 157 |
[[basic.stc.thread]]). The initial state for a thread’s floating-point
|
| 158 |
environment is the state of the floating-point environment of the thread
|
| 159 |
+
that constructs the corresponding `thread` object (
|
| 160 |
+
[[thread.thread.class]]) at the time it constructed the object.
|
| 161 |
+
|
| 162 |
+
[*Note 2*: That is, the child thread gets the floating-point state of
|
| 163 |
+
the parent thread at the time of the child’s creation. — *end note*]
|
| 164 |
|
| 165 |
A separate floating-point environment shall be maintained for each
|
| 166 |
thread. Each function accesses the environment corresponding to its
|
| 167 |
calling thread.
|
| 168 |
|
| 169 |
+
ISO C 7.6
|
| 170 |
+
|
| 171 |
## Complex numbers <a id="complex.numbers">[[complex.numbers]]</a>
|
| 172 |
|
| 173 |
The header `<complex>` defines a class template, and numerous functions
|
| 174 |
for representing and manipulating complex numbers.
|
| 175 |
|
|
|
|
| 179 |
`complex<long double>` are literal types ([[basic.types]]).
|
| 180 |
|
| 181 |
If the result of a function is not mathematically defined or not in the
|
| 182 |
range of representable values for its type, the behavior is undefined.
|
| 183 |
|
| 184 |
+
If `z` is an lvalue expression of type cv `complex<T>` then:
|
| 185 |
|
| 186 |
- the expression `reinterpret_cast<cv T(&)[2]>(z)` shall be well-formed,
|
| 187 |
- `reinterpret_cast<cv T(&)[2]>(z)[0]` shall designate the real part of
|
| 188 |
`z`, and
|
| 189 |
- `reinterpret_cast<cv T(&)[2]>(z)[1]` shall designate the imaginary
|
| 190 |
part of `z`.
|
| 191 |
|
| 192 |
+
Moreover, if `a` is an expression of type cv `complex<T>*` and the
|
| 193 |
expression `a[i]` is well-defined for an integer expression `i`, then:
|
| 194 |
|
| 195 |
- `reinterpret_cast<cv T*>(a)[2*i]` shall designate the real part of
|
| 196 |
`a[i]`, and
|
| 197 |
- `reinterpret_cast<cv T*>(a)[2*i + 1]` shall designate the imaginary
|
|
|
|
| 204 |
template<class T> class complex;
|
| 205 |
template<> class complex<float>;
|
| 206 |
template<> class complex<double>;
|
| 207 |
template<> class complex<long double>;
|
| 208 |
|
| 209 |
+
// [complex.ops], operators
|
| 210 |
template<class T>
|
| 211 |
complex<T> operator+(const complex<T>&, const complex<T>&);
|
| 212 |
template<class T> complex<T> operator+(const complex<T>&, const T&);
|
| 213 |
template<class T> complex<T> operator+(const T&, const complex<T>&);
|
| 214 |
|
|
|
|
| 245 |
|
| 246 |
template<class T, class charT, class traits>
|
| 247 |
basic_ostream<charT, traits>&
|
| 248 |
operator<<(basic_ostream<charT, traits>&, const complex<T>&);
|
| 249 |
|
| 250 |
+
// [complex.value.ops], values
|
| 251 |
template<class T> constexpr T real(const complex<T>&);
|
| 252 |
template<class T> constexpr T imag(const complex<T>&);
|
| 253 |
|
| 254 |
template<class T> T abs(const complex<T>&);
|
| 255 |
template<class T> T arg(const complex<T>&);
|
|
|
|
| 257 |
|
| 258 |
template<class T> complex<T> conj(const complex<T>&);
|
| 259 |
template<class T> complex<T> proj(const complex<T>&);
|
| 260 |
template<class T> complex<T> polar(const T&, const T& = 0);
|
| 261 |
|
| 262 |
+
// [complex.transcendentals], transcendentals
|
| 263 |
template<class T> complex<T> acos(const complex<T>&);
|
| 264 |
template<class T> complex<T> asin(const complex<T>&);
|
| 265 |
template<class T> complex<T> atan(const complex<T>&);
|
| 266 |
|
| 267 |
template<class T> complex<T> acosh(const complex<T>&);
|
|
|
|
| 282 |
template<class T> complex<T> sinh (const complex<T>&);
|
| 283 |
template<class T> complex<T> sqrt (const complex<T>&);
|
| 284 |
template<class T> complex<T> tan (const complex<T>&);
|
| 285 |
template<class T> complex<T> tanh (const complex<T>&);
|
| 286 |
|
| 287 |
+
// [complex.literals], complex literals
|
| 288 |
inline namespace literals {
|
| 289 |
inline namespace complex_literals {
|
| 290 |
constexpr complex<long double> operator""il(long double);
|
| 291 |
constexpr complex<long double> operator""il(unsigned long long);
|
| 292 |
constexpr complex<double> operator""i(long double);
|
|
|
|
| 303 |
``` cpp
|
| 304 |
namespace std {
|
| 305 |
template<class T>
|
| 306 |
class complex {
|
| 307 |
public:
|
| 308 |
+
using value_type = T;
|
| 309 |
|
| 310 |
constexpr complex(const T& re = T(), const T& im = T());
|
| 311 |
constexpr complex(const complex&);
|
| 312 |
template<class X> constexpr complex(const complex<X>&);
|
| 313 |
|
|
|
|
| 339 |
|
| 340 |
``` cpp
|
| 341 |
namespace std {
|
| 342 |
template<> class complex<float> {
|
| 343 |
public:
|
| 344 |
+
using value_type = float;
|
| 345 |
|
| 346 |
constexpr complex(float re = 0.0f, float im = 0.0f);
|
| 347 |
constexpr explicit complex(const complex<double>&);
|
| 348 |
constexpr explicit complex(const complex<long double>&);
|
| 349 |
|
|
|
|
| 366 |
template<class X> complex<float>& operator/=(const complex<X>&);
|
| 367 |
};
|
| 368 |
|
| 369 |
template<> class complex<double> {
|
| 370 |
public:
|
| 371 |
+
using value_type = double;
|
| 372 |
|
| 373 |
constexpr complex(double re = 0.0, double im = 0.0);
|
| 374 |
constexpr complex(const complex<float>&);
|
| 375 |
constexpr explicit complex(const complex<long double>&);
|
| 376 |
|
|
|
|
| 393 |
template<class X> complex<double>& operator/=(const complex<X>&);
|
| 394 |
};
|
| 395 |
|
| 396 |
template<> class complex<long double> {
|
| 397 |
public:
|
| 398 |
+
using value_type = long double;
|
| 399 |
|
| 400 |
constexpr complex(long double re = 0.0L, long double im = 0.0L);
|
| 401 |
constexpr complex(const complex<float>&);
|
| 402 |
constexpr complex(const complex<double>&);
|
| 403 |
|
|
|
|
| 428 |
template<class T> constexpr complex(const T& re = T(), const T& im = T());
|
| 429 |
```
|
| 430 |
|
| 431 |
*Effects:* Constructs an object of class `complex`.
|
| 432 |
|
| 433 |
+
*Postconditions:* `real() == re && imag() == im`.
|
| 434 |
|
| 435 |
``` cpp
|
| 436 |
constexpr T real() const;
|
| 437 |
```
|
| 438 |
|
|
|
|
| 536 |
|
| 537 |
``` cpp
|
| 538 |
template<class T> complex<T> operator+(const complex<T>& lhs);
|
| 539 |
```
|
| 540 |
|
|
|
|
|
|
|
| 541 |
*Returns:* `complex<T>(lhs)`.
|
| 542 |
|
| 543 |
+
*Remarks:* unary operator.
|
| 544 |
+
|
| 545 |
``` cpp
|
| 546 |
+
template<class T> complex<T> operator+(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 547 |
template<class T> complex<T> operator+(const complex<T>& lhs, const T& rhs);
|
| 548 |
template<class T> complex<T> operator+(const T& lhs, const complex<T>& rhs);
|
| 549 |
```
|
| 550 |
|
| 551 |
*Returns:* `complex<T>(lhs) += rhs`.
|
| 552 |
|
| 553 |
``` cpp
|
| 554 |
template<class T> complex<T> operator-(const complex<T>& lhs);
|
| 555 |
```
|
| 556 |
|
|
|
|
|
|
|
| 557 |
*Returns:* `complex<T>(-lhs.real(),-lhs.imag())`.
|
| 558 |
|
| 559 |
+
*Remarks:* unary operator.
|
| 560 |
+
|
| 561 |
``` cpp
|
| 562 |
+
template<class T> complex<T> operator-(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 563 |
template<class T> complex<T> operator-(const complex<T>& lhs, const T& rhs);
|
| 564 |
template<class T> complex<T> operator-(const T& lhs, const complex<T>& rhs);
|
| 565 |
```
|
| 566 |
|
| 567 |
*Returns:* `complex<T>(lhs) -= rhs`.
|
| 568 |
|
| 569 |
``` cpp
|
| 570 |
+
template<class T> complex<T> operator*(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 571 |
template<class T> complex<T> operator*(const complex<T>& lhs, const T& rhs);
|
| 572 |
template<class T> complex<T> operator*(const T& lhs, const complex<T>& rhs);
|
| 573 |
```
|
| 574 |
|
| 575 |
*Returns:* `complex<T>(lhs) *= rhs`.
|
| 576 |
|
| 577 |
``` cpp
|
| 578 |
+
template<class T> complex<T> operator/(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 579 |
template<class T> complex<T> operator/(const complex<T>& lhs, const T& rhs);
|
| 580 |
template<class T> complex<T> operator/(const T& lhs, const complex<T>& rhs);
|
| 581 |
```
|
| 582 |
|
| 583 |
*Returns:* `complex<T>(lhs) /= rhs`.
|
| 584 |
|
| 585 |
``` cpp
|
| 586 |
+
template<class T> constexpr bool operator==(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 587 |
template<class T> constexpr bool operator==(const complex<T>& lhs, const T& rhs);
|
| 588 |
template<class T> constexpr bool operator==(const T& lhs, const complex<T>& rhs);
|
| 589 |
```
|
| 590 |
|
| 591 |
*Returns:* `lhs.real() == rhs.real() && lhs.imag() == rhs.imag()`.
|
| 592 |
|
| 593 |
*Remarks:* The imaginary part is assumed to be `T()`, or 0.0, for the
|
| 594 |
`T` arguments.
|
| 595 |
|
| 596 |
``` cpp
|
| 597 |
+
template<class T> constexpr bool operator!=(const complex<T>& lhs, const complex<T>& rhs);
|
|
|
|
| 598 |
template<class T> constexpr bool operator!=(const complex<T>& lhs, const T& rhs);
|
| 599 |
template<class T> constexpr bool operator!=(const T& lhs, const complex<T>& rhs);
|
| 600 |
```
|
| 601 |
|
| 602 |
*Returns:* `rhs.real() != lhs.real() || rhs.imag() != lhs.imag()`.
|
|
|
|
| 605 |
template<class T, class charT, class traits>
|
| 606 |
basic_istream<charT, traits>&
|
| 607 |
operator>>(basic_istream<charT, traits>& is, complex<T>& x);
|
| 608 |
```
|
| 609 |
|
| 610 |
+
*Requires:* The input values shall be convertible to `T`.
|
| 611 |
+
|
| 612 |
*Effects:* Extracts a complex number `x` of the form: `u`, `(u)`, or
|
| 613 |
`(u,v)`, where `u` is the real part and `v` is the imaginary
|
| 614 |
part ([[istream.formatted]]).
|
| 615 |
|
|
|
|
|
|
|
| 616 |
If bad input is encountered, calls `is.setstate(ios_base::failbit)`
|
| 617 |
(which may throw `ios::failure` ([[iostate.flags]])).
|
| 618 |
|
| 619 |
*Returns:* `is`.
|
| 620 |
|
|
|
|
| 626 |
template<class T, class charT, class traits>
|
| 627 |
basic_ostream<charT, traits>&
|
| 628 |
operator<<(basic_ostream<charT, traits>& o, const complex<T>& x);
|
| 629 |
```
|
| 630 |
|
| 631 |
+
*Effects:* Inserts the complex number `x` onto the stream `o` as if it
|
| 632 |
were implemented as follows:
|
| 633 |
|
| 634 |
``` cpp
|
|
|
|
|
|
|
|
|
|
| 635 |
basic_ostringstream<charT, traits> s;
|
| 636 |
s.flags(o.flags());
|
| 637 |
s.imbue(o.getloc());
|
| 638 |
s.precision(o.precision());
|
| 639 |
s << '(' << x.real() << "," << x.imag() << ')';
|
| 640 |
return o << s.str();
|
|
|
|
| 641 |
```
|
| 642 |
|
| 643 |
+
[*Note 1*: In a locale in which comma is used as a decimal point
|
| 644 |
+
character, the use of comma as a field separator can be ambiguous.
|
| 645 |
+
Inserting `showpoint` into the output stream forces all outputs to show
|
| 646 |
+
an explicit decimal point character; as a result, all inserted sequences
|
| 647 |
+
of complex numbers can be extracted unambiguously. — *end note*]
|
| 648 |
|
| 649 |
### `complex` value operations <a id="complex.value.ops">[[complex.value.ops]]</a>
|
| 650 |
|
| 651 |
``` cpp
|
| 652 |
template<class T> constexpr T real(const complex<T>& x);
|
|
|
|
| 695 |
|
| 696 |
``` cpp
|
| 697 |
template<class T> complex<T> polar(const T& rho, const T& theta = 0);
|
| 698 |
```
|
| 699 |
|
| 700 |
+
*Requires:* `rho` shall be non-negative and non-NaN. `theta` shall be
|
| 701 |
+
finite.
|
| 702 |
+
|
| 703 |
*Returns:* The `complex` value corresponding to a complex number whose
|
| 704 |
magnitude is `rho` and whose phase angle is `theta`.
|
| 705 |
|
| 706 |
### `complex` transcendentals <a id="complex.transcendentals">[[complex.transcendentals]]</a>
|
| 707 |
|
|
|
|
| 767 |
|
| 768 |
``` cpp
|
| 769 |
template<class T> complex<T> exp(const complex<T>& x);
|
| 770 |
```
|
| 771 |
|
| 772 |
+
*Returns:* The complex base-e exponential of `x`.
|
| 773 |
|
| 774 |
``` cpp
|
| 775 |
template<class T> complex<T> log(const complex<T>& x);
|
| 776 |
```
|
| 777 |
|
| 778 |
+
*Returns:* The complex natural (base-e) logarithm of `x`. For all `x`,
|
| 779 |
+
`imag(log(x))` lies in the interval \[-π, π\], and when `x` is a
|
| 780 |
+
negative real number, `imag(log(x))` is π.
|
| 781 |
|
| 782 |
+
*Remarks:* The branch cuts are along the negative real axis.
|
|
|
|
|
|
|
|
|
|
| 783 |
|
| 784 |
``` cpp
|
| 785 |
template<class T> complex<T> log10(const complex<T>& x);
|
| 786 |
```
|
| 787 |
|
| 788 |
+
*Returns:* The complex common (base-10) logarithm of `x`, defined as
|
|
|
|
|
|
|
| 789 |
`log(x) / log(10)`.
|
| 790 |
|
| 791 |
+
*Remarks:* The branch cuts are along the negative real axis.
|
| 792 |
+
|
| 793 |
``` cpp
|
| 794 |
+
template<class T> complex<T> pow(const complex<T>& x, const complex<T>& y);
|
|
|
|
| 795 |
template<class T> complex<T> pow(const complex<T>& x, const T& y);
|
| 796 |
template<class T> complex<T> pow(const T& x, const complex<T>& y);
|
| 797 |
```
|
| 798 |
|
| 799 |
+
*Returns:* The complex power of base `x` raised to the `y`ᵗʰ power,
|
|
|
|
|
|
|
| 800 |
defined as `exp(y * log(x))`. The value returned for `pow(0, 0)` is
|
| 801 |
+
*implementation-defined*.
|
| 802 |
+
|
| 803 |
+
*Remarks:* The branch cuts are along the negative real axis.
|
| 804 |
|
| 805 |
``` cpp
|
| 806 |
template<class T> complex<T> sin(const complex<T>& x);
|
| 807 |
```
|
| 808 |
|
|
|
|
| 816 |
|
| 817 |
``` cpp
|
| 818 |
template<class T> complex<T> sqrt(const complex<T>& x);
|
| 819 |
```
|
| 820 |
|
|
|
|
|
|
|
| 821 |
*Returns:* The complex square root of `x`, in the range of the right
|
| 822 |
half-plane. If the argument is a negative real number, the value
|
| 823 |
returned lies on the positive imaginary axis.
|
| 824 |
|
| 825 |
+
*Remarks:* The branch cuts are along the negative real axis.
|
| 826 |
+
|
| 827 |
``` cpp
|
| 828 |
template<class T> complex<T> tan(const complex<T>& x);
|
| 829 |
```
|
| 830 |
|
| 831 |
*Returns:* The complex tangent of `x`.
|
|
|
|
| 894 |
constexpr complex<float> operator""if(unsigned long long d);
|
| 895 |
```
|
| 896 |
|
| 897 |
*Returns:* `complex<float>{0.0f, static_cast<float>(d)}`.
|
| 898 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| 899 |
## Random number generation <a id="rand">[[rand]]</a>
|
| 900 |
|
| 901 |
This subclause defines a facility for generating (pseudo-)random
|
| 902 |
numbers.
|
| 903 |
|
| 904 |
In addition to a few utilities, four categories of entities are
|
| 905 |
+
described: *uniform random bit generators*, *random number engines*,
|
| 906 |
*random number engine adaptors*, and *random number distributions*.
|
| 907 |
These categorizations are applicable to types that satisfy the
|
| 908 |
corresponding requirements, to objects instantiated from such types, and
|
| 909 |
+
to templates producing such types when instantiated.
|
| 910 |
+
|
| 911 |
+
[*Note 1*: These entities are specified in such a way as to permit the
|
| 912 |
+
binding of any uniform random bit generator object `e` as the argument
|
| 913 |
+
to any random number distribution object `d`, thus producing a
|
| 914 |
+
zero-argument function object such as given by
|
| 915 |
+
`bind(d,e)`. — *end note*]
|
| 916 |
|
| 917 |
Each of the entities specified via this subclause has an associated
|
| 918 |
arithmetic type ([[basic.fundamental]]) identified as `result_type`.
|
| 919 |
With `T` as the `result_type` thus associated with such an entity, that
|
| 920 |
entity is characterized:
|
|
|
|
| 936 |
template:
|
| 937 |
|
| 938 |
Throughout this subclause [[rand]], phrases of the form “`x` is an
|
| 939 |
iterator of a specific kind” shall be interpreted as equivalent to the
|
| 940 |
more formal requirement that “`x` is a value of a type satisfying the
|
| 941 |
+
requirements of the specified iterator type”.
|
| 942 |
|
| 943 |
Throughout this subclause [[rand]], any constructor that can be called
|
| 944 |
with a single argument and that satisfies a requirement specified in
|
| 945 |
this subclause shall be declared `explicit`.
|
| 946 |
|
| 947 |
#### Seed sequence requirements <a id="rand.req.seedseq">[[rand.req.seedseq]]</a>
|
| 948 |
|
| 949 |
A *seed sequence* is an object that consumes a sequence of
|
| 950 |
integer-valued data and produces a requested number of unsigned integer
|
| 951 |
+
values i, 0 ≤ i < 2³², based on the consumed data.
|
| 952 |
+
|
| 953 |
+
[*Note 1*: Such an object provides a mechanism to avoid replication of
|
| 954 |
+
streams of random variates. This can be useful, for example, in
|
| 955 |
+
applications requiring large numbers of random number
|
| 956 |
+
engines. — *end note*]
|
| 957 |
|
| 958 |
A class `S` satisfies the requirements of a seed sequence if the
|
| 959 |
expressions shown in Table [[tab:SeedSequence]] are valid and have the
|
| 960 |
indicated semantics, and if `S` also satisfies all other requirements of
|
| 961 |
this section [[rand.req.seedseq]]. In that Table and throughout this
|
| 962 |
section:
|
| 963 |
|
| 964 |
+
#### Uniform random bit generator requirements <a id="rand.req.urng">[[rand.req.urng]]</a>
|
| 965 |
|
| 966 |
+
A *uniform random bit generator* `g` of type `G` is a function object
|
| 967 |
returning unsigned integer values such that each value in the range of
|
| 968 |
+
possible results has (ideally) equal probability of being returned.
|
|
|
|
|
|
|
| 969 |
|
| 970 |
+
[*Note 1*: The degree to which `g`’s results approximate the ideal is
|
| 971 |
+
often determined statistically. — *end note*]
|
| 972 |
+
|
| 973 |
+
A class `G` satisfies the requirements of a *uniform random bit
|
| 974 |
generator* if the expressions shown in Table
|
| 975 |
+
[[tab:UniformRandomBitGenerator]] are valid and have the indicated
|
| 976 |
semantics, and if `G` also satisfies all other requirements of this
|
| 977 |
section [[rand.req.urng]]. In that Table and throughout this section:
|
| 978 |
|
| 979 |
The following relation shall hold: `G::min() < G::max()`.
|
| 980 |
|
| 981 |
#### Random number engine requirements <a id="rand.req.eng">[[rand.req.eng]]</a>
|
| 982 |
|
| 983 |
A *random number engine* (commonly shortened to *engine*) `e` of type
|
| 984 |
+
`E` is a uniform random bit generator that additionally meets the
|
| 985 |
+
requirements (e.g., for seeding and for input/output) specified in this
|
| 986 |
+
section.
|
| 987 |
|
| 988 |
At any given time, `e` has a state eᵢ for some integer i ≥ 0. Upon
|
| 989 |
construction, `e` has an initial state e₀. An engine’s state may be
|
| 990 |
established via a constructor, a `seed` function, assignment, or a
|
| 991 |
suitable `operator>>`.
|
| 992 |
|
| 993 |
`E`’s specification shall define:
|
| 994 |
|
| 995 |
+
A class `E` that satisfies the requirements of a uniform random bit
|
| 996 |
generator ([[rand.req.urng]]) also satisfies the requirements of a
|
| 997 |
*random number engine* if the expressions shown in Table
|
| 998 |
[[tab:RandomEngine]] are valid and have the indicated semantics, and if
|
| 999 |
`E` also satisfies all other requirements of this section
|
| 1000 |
[[rand.req.eng]]. In that Table and throughout this section:
|
| 1001 |
|
| 1002 |
where `charT` and `traits` are constrained according to Clause
|
| 1003 |
[[strings]] and Clause [[input.output]].
|
| 1004 |
|
| 1005 |
`E` shall meet the requirements of `CopyConstructible` (Table
|
| 1006 |
+
[[tab:copyconstructible]]) and `CopyAssignable` (Table
|
| 1007 |
+
[[tab:copyassignable]]) types. These operations shall each be of
|
| 1008 |
+
complexity no worse than 𝑂(\mbox{size of state}).
|
| 1009 |
|
| 1010 |
#### Random number engine adaptor requirements <a id="rand.req.adapt">[[rand.req.adapt]]</a>
|
| 1011 |
|
| 1012 |
A *random number engine adaptor* (commonly shortened to *adaptor*) `a`
|
| 1013 |
of type `A` is a random number engine that takes values produced by some
|
|
|
|
| 1039 |
```
|
| 1040 |
|
| 1041 |
*Effects:* The base engine is initialized with `s`.
|
| 1042 |
|
| 1043 |
``` cpp
|
| 1044 |
+
template<class Sseq> A::A(Sseq& q);
|
| 1045 |
```
|
| 1046 |
|
| 1047 |
*Effects:* The base engine is initialized with `q`.
|
| 1048 |
|
| 1049 |
``` cpp
|
|
|
|
| 1091 |
|
| 1092 |
where `charT` and `traits` are constrained according to Clauses
|
| 1093 |
[[strings]] and [[input.output]].
|
| 1094 |
|
| 1095 |
`D` shall satisfy the requirements of `CopyConstructible` (Table
|
| 1096 |
+
[[tab:copyconstructible]]) and `CopyAssignable` (Table
|
| 1097 |
+
[[tab:copyassignable]]) types.
|
| 1098 |
|
| 1099 |
The sequence of numbers produced by repeated invocations of `d(g)` shall
|
| 1100 |
be independent of any invocation of `os << d` or of any `const` member
|
| 1101 |
function of `D` between any of the invocations `d(g)`.
|
| 1102 |
|
|
|
|
| 1110 |
`class` or via a `typedef`. In this subclause [[rand]], declarations of
|
| 1111 |
`D::param_type` are in the form of `typedef`s for convenience of
|
| 1112 |
exposition only.
|
| 1113 |
|
| 1114 |
`P` shall satisfy the requirements of `CopyConstructible` (Table
|
| 1115 |
+
[[tab:copyconstructible]]), `CopyAssignable` (Table
|
| 1116 |
+
[[tab:copyassignable]]), and `EqualityComparable` (Table
|
| 1117 |
+
[[tab:equalitycomparable]]) types.
|
| 1118 |
|
| 1119 |
For each of the constructors of `D` taking arguments corresponding to
|
| 1120 |
parameters of the distribution, `P` shall have a corresponding
|
| 1121 |
constructor subject to the same requirements and taking arguments
|
| 1122 |
identical in number, type, and default values. Moreover, for each of the
|
|
|
|
| 1125 |
the identical name, type, and semantics.
|
| 1126 |
|
| 1127 |
`P` shall have a declaration of the form
|
| 1128 |
|
| 1129 |
``` cpp
|
| 1130 |
+
using distribution_type = D;
|
| 1131 |
```
|
| 1132 |
|
| 1133 |
### Header `<random>` synopsis <a id="rand.synopsis">[[rand.synopsis]]</a>
|
| 1134 |
|
| 1135 |
``` cpp
|
| 1136 |
#include <initializer_list>
|
| 1137 |
|
| 1138 |
namespace std {
|
|
|
|
| 1139 |
// [rand.eng.lcong], class template linear_congruential_engine
|
| 1140 |
template<class UIntType, UIntType a, UIntType c, UIntType m>
|
| 1141 |
class linear_congruential_engine;
|
| 1142 |
|
| 1143 |
// [rand.eng.mers], class template mersenne_twister_engine
|
|
|
|
| 1162 |
// [rand.adapt.shuf], class template shuffle_order_engine
|
| 1163 |
template<class Engine, size_t k>
|
| 1164 |
class shuffle_order_engine;
|
| 1165 |
|
| 1166 |
// [rand.predef], engines and engine adaptors with predefined parameters
|
| 1167 |
+
using minstd_rand0 = see below;
|
| 1168 |
+
using minstd_rand = see below;
|
| 1169 |
+
using mt19937 = see below;
|
| 1170 |
+
using mt19937_64 = see below;
|
| 1171 |
+
using ranlux24_base = see below;
|
| 1172 |
+
using ranlux48_base = see below;
|
| 1173 |
+
using ranlux24 = see below;
|
| 1174 |
+
using ranlux48 = see below;
|
| 1175 |
+
using knuth_b = see below;
|
| 1176 |
+
|
| 1177 |
+
using default_random_engine = see below;
|
| 1178 |
|
| 1179 |
// [rand.device], class random_device
|
| 1180 |
class random_device;
|
| 1181 |
|
| 1182 |
// [rand.util.seedseq], class seed_seq
|
| 1183 |
class seed_seq;
|
| 1184 |
|
| 1185 |
// [rand.util.canonical], function template generate_canonical
|
| 1186 |
+
template<class RealType, size_t bits, class URBG>
|
| 1187 |
+
RealType generate_canonical(URBG& g);
|
| 1188 |
|
| 1189 |
// [rand.dist.uni.int], class template uniform_int_distribution
|
| 1190 |
template<class IntType = int>
|
| 1191 |
class uniform_int_distribution;
|
| 1192 |
|
|
|
|
| 1262 |
class piecewise_constant_distribution;
|
| 1263 |
|
| 1264 |
// [rand.dist.samp.plinear], class template piecewise_linear_distribution
|
| 1265 |
template<class RealType = double>
|
| 1266 |
class piecewise_linear_distribution;
|
| 1267 |
+
}
|
|
|
|
| 1268 |
```
|
| 1269 |
|
| 1270 |
### Random number engine class templates <a id="rand.eng">[[rand.eng]]</a>
|
| 1271 |
|
| 1272 |
Each type instantiated from a class template specified in this section
|
|
|
|
| 1277 |
specified in this section [[rand.eng]] is constant.
|
| 1278 |
|
| 1279 |
Except where specified otherwise, no function described in this section
|
| 1280 |
[[rand.eng]] throws an exception.
|
| 1281 |
|
| 1282 |
+
Every function described in this section [[rand.eng]] that has a
|
| 1283 |
+
function parameter `q` of type `Sseq&` for a template type parameter
|
| 1284 |
+
named `Sseq` that is different from type `seed_seq` throws what and when
|
| 1285 |
+
the invocation of `q.generate` throws.
|
| 1286 |
+
|
| 1287 |
Descriptions are provided in this section [[rand.eng]] only for engine
|
| 1288 |
+
operations that are not described in [[rand.req.eng]] or for operations
|
| 1289 |
+
where there is additional semantic information. In particular,
|
| 1290 |
+
declarations for copy constructors, for copy assignment operators, for
|
| 1291 |
+
streaming operators, and for equality and inequality operators are not
|
| 1292 |
+
shown in the synopses.
|
| 1293 |
|
| 1294 |
Each template specified in this section [[rand.eng]] requires one or
|
| 1295 |
more relationships, involving the value(s) of its non-type template
|
| 1296 |
parameter(s), to hold. A program instantiating any of these templates is
|
| 1297 |
ill-formed if any such required relationship fails to hold.
|
| 1298 |
|
| 1299 |
For every random number engine and for every random number engine
|
| 1300 |
+
adaptor `X` defined in this subclause ([[rand.eng]]) and in subclause
|
| 1301 |
+
[[rand.adapt]]:
|
| 1302 |
|
| 1303 |
- if the constructor
|
| 1304 |
``` cpp
|
| 1305 |
template <class Sseq> explicit X(Sseq& q);
|
| 1306 |
```
|
|
|
|
| 1329 |
TA(xᵢ) = (a ⋅ xᵢ + c) mod m; the generation algorithm is
|
| 1330 |
GA(xᵢ) = xᵢ₊₁.
|
| 1331 |
|
| 1332 |
``` cpp
|
| 1333 |
template<class UIntType, UIntType a, UIntType c, UIntType m>
|
| 1334 |
+
class linear_congruential_engine {
|
|
|
|
| 1335 |
public:
|
| 1336 |
// types
|
| 1337 |
+
using result_type = UIntType;
|
| 1338 |
|
| 1339 |
// engine characteristics
|
| 1340 |
static constexpr result_type multiplier = a;
|
| 1341 |
static constexpr result_type increment = c;
|
| 1342 |
static constexpr result_type modulus = m;
|
|
|
|
| 1356 |
};
|
| 1357 |
```
|
| 1358 |
|
| 1359 |
If the template parameter `m` is 0, the modulus m used throughout this
|
| 1360 |
section [[rand.eng.lcong]] is `numeric_limits<result_type>::max()` plus
|
| 1361 |
+
1.
|
| 1362 |
+
|
| 1363 |
+
[*Note 1*: m need not be representable as a value of type
|
| 1364 |
+
`result_type`. — *end note*]
|
| 1365 |
|
| 1366 |
If the template parameter `m` is not 0, the following relations shall
|
| 1367 |
hold: `a < m` and `c < m`.
|
| 1368 |
|
| 1369 |
The textual representation consists of the value of xᵢ.
|
|
|
|
| 1398 |
applied to X are to be taken modulo n.
|
| 1399 |
|
| 1400 |
The transition algorithm employs a twisted generalized feedback shift
|
| 1401 |
register defined by shift values n and m, a twist value r, and a
|
| 1402 |
conditional xor-mask a. To improve the uniformity of the result, the
|
| 1403 |
+
bits of the raw shift register are additionally *tempered* (i.e.,
|
| 1404 |
scrambled) according to a bit-scrambling matrix defined by values
|
| 1405 |
u, d, s, b, t, c, and ℓ.
|
| 1406 |
|
| 1407 |
The state transition is performed as follows:
|
| 1408 |
|
|
|
|
| 1415 |
``` cpp
|
| 1416 |
template<class UIntType, size_t w, size_t n, size_t m, size_t r,
|
| 1417 |
UIntType a, size_t u, UIntType d, size_t s,
|
| 1418 |
UIntType b, size_t t,
|
| 1419 |
UIntType c, size_t l, UIntType f>
|
| 1420 |
+
class mersenne_twister_engine {
|
|
|
|
| 1421 |
public:
|
| 1422 |
// types
|
| 1423 |
+
using result_type = UIntType;
|
| 1424 |
|
| 1425 |
// engine characteristics
|
| 1426 |
static constexpr size_t word_size = w;
|
| 1427 |
static constexpr size_t state_size = n;
|
| 1428 |
static constexpr size_t shift_size = m;
|
|
|
|
| 1499 |
additionally consists of an integer c (known as the *carry*) whose value
|
| 1500 |
is either 0 or 1.
|
| 1501 |
|
| 1502 |
The state transition is performed as follows:
|
| 1503 |
|
| 1504 |
+
[*Note 1*: This algorithm corresponds to a modular linear function of
|
| 1505 |
+
the form TA(xᵢ) = (a ⋅ xᵢ) mod b, where b is of the form mʳ - mˢ + 1
|
| 1506 |
+
and a = b - (b-1) / m. — *end note*]
|
| 1507 |
|
| 1508 |
The generation algorithm is given by GA(xᵢ) = y, where y is the value
|
| 1509 |
produced as a result of advancing the engine’s state as described above.
|
| 1510 |
|
| 1511 |
``` cpp
|
| 1512 |
template<class UIntType, size_t w, size_t s, size_t r>
|
| 1513 |
+
class subtract_with_carry_engine {
|
|
|
|
| 1514 |
public:
|
| 1515 |
// types
|
| 1516 |
+
using result_type = UIntType;
|
| 1517 |
|
| 1518 |
// engine characteristics
|
| 1519 |
static constexpr size_t word_size = w;
|
| 1520 |
static constexpr size_t short_lag = s;
|
| 1521 |
static constexpr size_t long_lag = r;
|
|
|
|
| 1577 |
### Random number engine adaptor class templates <a id="rand.adapt">[[rand.adapt]]</a>
|
| 1578 |
|
| 1579 |
#### In general <a id="rand.adapt.general">[[rand.adapt.general]]</a>
|
| 1580 |
|
| 1581 |
Each type instantiated from a class template specified in this section
|
| 1582 |
+
[[rand.adapt]] satisfies the requirements of a random number engine
|
| 1583 |
adaptor ([[rand.req.adapt]]) type.
|
| 1584 |
|
| 1585 |
Except where specified otherwise, the complexity of each function
|
| 1586 |
specified in this section [[rand.adapt]] is constant.
|
| 1587 |
|
| 1588 |
Except where specified otherwise, no function described in this section
|
| 1589 |
[[rand.adapt]] throws an exception.
|
| 1590 |
|
| 1591 |
+
Every function described in this section [[rand.adapt]] that has a
|
| 1592 |
+
function parameter `q` of type `Sseq&` for a template type parameter
|
| 1593 |
+
named `Sseq` that is different from type `seed_seq` throws what and when
|
| 1594 |
+
the invocation of `q.generate` throws.
|
| 1595 |
+
|
| 1596 |
Descriptions are provided in this section [[rand.adapt]] only for
|
| 1597 |
adaptor operations that are not described in section [[rand.req.adapt]]
|
| 1598 |
or for operations where there is additional semantic information. In
|
| 1599 |
particular, declarations for copy constructors, for copy assignment
|
| 1600 |
operators, for streaming operators, and for equality and inequality
|
|
|
|
| 1622 |
The generation algorithm yields the value returned by the last
|
| 1623 |
invocation of `e()` while advancing `e`’s state as described above.
|
| 1624 |
|
| 1625 |
``` cpp
|
| 1626 |
template<class Engine, size_t p, size_t r>
|
| 1627 |
+
class discard_block_engine {
|
|
|
|
| 1628 |
public:
|
| 1629 |
// types
|
| 1630 |
+
using result_type = typename Engine::result_type;
|
| 1631 |
|
| 1632 |
// engine characteristics
|
| 1633 |
static constexpr size_t block_size = p;
|
| 1634 |
static constexpr size_t used_block = r;
|
| 1635 |
static constexpr result_type min() { return Engine::min(); }
|
|
|
|
| 1676 |
e’s state.
|
| 1677 |
|
| 1678 |
The transition and generation algorithms are described in terms of the
|
| 1679 |
following integral constants:
|
| 1680 |
|
| 1681 |
+
[*Note 1*: The relation w = n₀ w₀ + (n - n₀)(w₀ + 1) always
|
| 1682 |
+
holds. — *end note*]
|
| 1683 |
|
| 1684 |
The transition algorithm is carried out by invoking `e()` as often as
|
| 1685 |
needed to obtain n₀ values less than y₀ + `e.min()` and n - n₀ values
|
| 1686 |
less than y₁ + `e.min()` .
|
| 1687 |
|
|
|
|
| 1701 |
}
|
| 1702 |
```
|
| 1703 |
|
| 1704 |
``` cpp
|
| 1705 |
template<class Engine, size_t w, class UIntType>
|
| 1706 |
+
class independent_bits_engine {
|
|
|
|
| 1707 |
public:
|
| 1708 |
// types
|
| 1709 |
+
using result_type = UIntType;
|
| 1710 |
|
| 1711 |
// engine characteristics
|
| 1712 |
static constexpr result_type min() { return 0; }
|
| 1713 |
static constexpr result_type max() { return 2^w - 1; }
|
| 1714 |
|
|
|
|
| 1756 |
The generation algorithm yields the last value of `Y` produced while
|
| 1757 |
advancing `e`’s state as described above.
|
| 1758 |
|
| 1759 |
``` cpp
|
| 1760 |
template<class Engine, size_t k>
|
| 1761 |
+
class shuffle_order_engine {
|
|
|
|
| 1762 |
public:
|
| 1763 |
// types
|
| 1764 |
+
using result_type = typename Engine::result_type;
|
| 1765 |
|
| 1766 |
// engine characteristics
|
| 1767 |
static constexpr size_t table_size = k;
|
| 1768 |
static constexpr result_type min() { return Engine::min(); }
|
| 1769 |
static constexpr result_type max() { return Engine::max(); }
|
|
|
|
| 1785 |
// property functions
|
| 1786 |
const Engine& base() const noexcept { return e; };
|
| 1787 |
|
| 1788 |
private:
|
| 1789 |
Engine e; // exposition only
|
|
|
|
| 1790 |
result_type V[k]; // exposition only
|
| 1791 |
+
result_type Y; // exposition only
|
| 1792 |
};
|
| 1793 |
```
|
| 1794 |
|
| 1795 |
The following relation shall hold: `0 < k`.
|
| 1796 |
|
|
|
|
| 1803 |
successive invocations of `e()`.
|
| 1804 |
|
| 1805 |
### Engines and engine adaptors with predefined parameters <a id="rand.predef">[[rand.predef]]</a>
|
| 1806 |
|
| 1807 |
``` cpp
|
| 1808 |
+
using minstd_rand0 =
|
| 1809 |
+
linear_congruential_engine<uint_fast32_t, 16807, 0, 2147483647>;
|
| 1810 |
```
|
| 1811 |
|
| 1812 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1813 |
default-constructed object of type `minstd_rand0` shall produce the
|
| 1814 |
value 1043618065.
|
| 1815 |
|
| 1816 |
``` cpp
|
| 1817 |
+
using minstd_rand =
|
| 1818 |
+
linear_congruential_engine<uint_fast32_t, 48271, 0, 2147483647>;
|
| 1819 |
```
|
| 1820 |
|
| 1821 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1822 |
default-constructed object of type `minstd_rand` shall produce the value
|
| 1823 |
399268537.
|
| 1824 |
|
| 1825 |
``` cpp
|
| 1826 |
+
using mt19937 =
|
| 1827 |
+
mersenne_twister_engine<uint_fast32_t,
|
| 1828 |
+
32,624,397,31,0x9908b0df,11,0xffffffff,7,0x9d2c5680,15,0xefc60000,18,1812433253>;
|
| 1829 |
```
|
| 1830 |
|
| 1831 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1832 |
default-constructed object of type `mt19937` shall produce the value
|
| 1833 |
4123659995.
|
| 1834 |
|
| 1835 |
``` cpp
|
| 1836 |
+
using mt19937_64 =
|
| 1837 |
+
mersenne_twister_engine<uint_fast64_t,
|
| 1838 |
64,312,156,31,0xb5026f5aa96619e9,29,
|
| 1839 |
0x5555555555555555,17,
|
| 1840 |
0x71d67fffeda60000,37,
|
| 1841 |
0xfff7eee000000000,43,
|
| 1842 |
+
6364136223846793005>;
|
|
|
|
| 1843 |
```
|
| 1844 |
|
| 1845 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1846 |
default-constructed object of type `mt19937_64` shall produce the value
|
| 1847 |
9981545732273789042.
|
| 1848 |
|
| 1849 |
``` cpp
|
| 1850 |
+
using ranlux24_base =
|
| 1851 |
+
subtract_with_carry_engine<uint_fast32_t, 24, 10, 24>;
|
| 1852 |
```
|
| 1853 |
|
| 1854 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1855 |
default-constructed object of type `ranlux24_base` shall produce the
|
| 1856 |
value 7937952.
|
| 1857 |
|
| 1858 |
``` cpp
|
| 1859 |
+
using ranlux48_base =
|
| 1860 |
+
subtract_with_carry_engine<uint_fast64_t, 48, 5, 12>;
|
| 1861 |
```
|
| 1862 |
|
| 1863 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1864 |
default-constructed object of type `ranlux48_base` shall produce the
|
| 1865 |
value 61839128582725.
|
| 1866 |
|
| 1867 |
``` cpp
|
| 1868 |
+
using ranlux24 = discard_block_engine<ranlux24_base, 223, 23>;
|
|
|
|
| 1869 |
```
|
| 1870 |
|
| 1871 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1872 |
default-constructed object of type `ranlux24` shall produce the value
|
| 1873 |
9901578.
|
| 1874 |
|
| 1875 |
``` cpp
|
| 1876 |
+
using ranlux48 = discard_block_engine<ranlux48_base, 389, 11>;
|
|
|
|
| 1877 |
```
|
| 1878 |
|
| 1879 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1880 |
default-constructed object of type `ranlux48` shall produce the value
|
| 1881 |
249142670248501.
|
| 1882 |
|
| 1883 |
``` cpp
|
| 1884 |
+
using knuth_b = shuffle_order_engine<minstd_rand0,256>;
|
|
|
|
| 1885 |
```
|
| 1886 |
|
| 1887 |
*Required behavior:* The $10000^{\,th}$ consecutive invocation of a
|
| 1888 |
default-constructed object of type `knuth_b` shall produce the value
|
| 1889 |
1112339016.
|
| 1890 |
|
| 1891 |
``` cpp
|
| 1892 |
+
using default_random_engine = implementation-defined;
|
|
|
|
| 1893 |
```
|
| 1894 |
|
| 1895 |
+
*Remarks:* The choice of engine type named by this `typedef` is
|
| 1896 |
+
*implementation-defined*.
|
| 1897 |
+
|
| 1898 |
+
[*Note 1*: The implementation may select this type on the basis of
|
| 1899 |
+
performance, size, quality, or any combination of such factors, so as to
|
| 1900 |
+
provide at least acceptable engine behavior for relatively casual,
|
| 1901 |
+
inexpert, and/or lightweight use. Because different implementations may
|
| 1902 |
+
select different underlying engine types, code that uses this `typedef`
|
| 1903 |
+
need not generate identical sequences across
|
| 1904 |
+
implementations. — *end note*]
|
| 1905 |
|
| 1906 |
### Class `random_device` <a id="rand.device">[[rand.device]]</a>
|
| 1907 |
|
| 1908 |
+
A `random_device` uniform random bit generator produces nondeterministic
|
| 1909 |
+
random numbers.
|
| 1910 |
|
| 1911 |
+
If implementation limitations prevent generating nondeterministic random
|
| 1912 |
+
numbers, the implementation may employ a random number engine.
|
| 1913 |
|
| 1914 |
``` cpp
|
| 1915 |
+
class random_device {
|
|
|
|
| 1916 |
public:
|
| 1917 |
// types
|
| 1918 |
+
using result_type = unsigned int;
|
| 1919 |
|
| 1920 |
// generator characteristics
|
| 1921 |
static constexpr result_type min() { return numeric_limits<result_type>::min(); }
|
| 1922 |
static constexpr result_type max() { return numeric_limits<result_type>::max(); }
|
| 1923 |
|
|
|
|
| 1938 |
|
| 1939 |
``` cpp
|
| 1940 |
explicit random_device(const string& token = implementation-defined);
|
| 1941 |
```
|
| 1942 |
|
| 1943 |
+
*Effects:* Constructs a `random_device` nondeterministic uniform random
|
| 1944 |
+
bit generator object. The semantics and default value of the `token`
|
| 1945 |
+
parameter are *implementation-defined*. [^3]
|
| 1946 |
|
| 1947 |
+
*Throws:* A value of an *implementation-defined* type derived from
|
| 1948 |
`exception` if the `random_device` could not be initialized.
|
| 1949 |
|
| 1950 |
``` cpp
|
| 1951 |
double entropy() const noexcept;
|
| 1952 |
```
|
|
|
|
| 1957 |
|
| 1958 |
``` cpp
|
| 1959 |
result_type operator()();
|
| 1960 |
```
|
| 1961 |
|
| 1962 |
+
*Returns:* A nondeterministic random value, uniformly distributed
|
| 1963 |
+
between `min()` and `max()`, inclusive. It is *implementation-defined*
|
| 1964 |
+
how these values are generated.
|
| 1965 |
|
| 1966 |
+
*Throws:* A value of an *implementation-defined* type derived from
|
| 1967 |
`exception` if a random number could not be obtained.
|
| 1968 |
|
| 1969 |
### Utilities <a id="rand.util">[[rand.util]]</a>
|
| 1970 |
|
| 1971 |
#### Class `seed_seq` <a id="rand.util.seedseq">[[rand.util.seedseq]]</a>
|
| 1972 |
|
| 1973 |
``` cpp
|
| 1974 |
+
class seed_seq {
|
|
|
|
| 1975 |
public:
|
| 1976 |
// types
|
| 1977 |
+
using result_type = uint_least32_t;
|
| 1978 |
|
| 1979 |
// constructors
|
| 1980 |
seed_seq();
|
| 1981 |
template<class T>
|
| 1982 |
seed_seq(initializer_list<T> il);
|
|
|
|
| 1986 |
// generating functions
|
| 1987 |
template<class RandomAccessIterator>
|
| 1988 |
void generate(RandomAccessIterator begin, RandomAccessIterator end);
|
| 1989 |
|
| 1990 |
// property functions
|
| 1991 |
+
size_t size() const noexcept;
|
| 1992 |
template<class OutputIterator>
|
| 1993 |
void param(OutputIterator dest) const;
|
| 1994 |
|
| 1995 |
// no copy functions
|
| 1996 |
seed_seq(const seed_seq& ) = delete;
|
|
|
|
| 2040 |
template<class RandomAccessIterator>
|
| 2041 |
void generate(RandomAccessIterator begin, RandomAccessIterator end);
|
| 2042 |
```
|
| 2043 |
|
| 2044 |
*Requires:* `RandomAccessIterator` shall meet the requirements of a
|
| 2045 |
+
mutable random access iterator ([[random.access.iterators]]). Moreover,
|
|
|
|
| 2046 |
`iterator_traits<RandomAccessIterator>::value_type` shall denote an
|
| 2047 |
unsigned integer type capable of accommodating 32-bit quantities.
|
| 2048 |
|
| 2049 |
*Effects:* Does nothing if `begin == end`. Otherwise, with
|
| 2050 |
s = `v.size()` and n = `end` - `begin`, fills the supplied range
|
|
|
|
| 2055 |
|
| 2056 |
*Throws:* What and when `RandomAccessIterator` operations of `begin` and
|
| 2057 |
`end` throw.
|
| 2058 |
|
| 2059 |
``` cpp
|
| 2060 |
+
size_t size() const noexcept;
|
| 2061 |
```
|
| 2062 |
|
| 2063 |
*Returns:* The number of 32-bit units that would be returned by a call
|
| 2064 |
to `param()`.
|
| 2065 |
|
|
|
|
|
|
|
| 2066 |
*Complexity:* Constant time.
|
| 2067 |
|
| 2068 |
``` cpp
|
| 2069 |
template<class OutputIterator>
|
| 2070 |
void param(OutputIterator dest) const;
|
| 2071 |
```
|
| 2072 |
|
| 2073 |
*Requires:* `OutputIterator` shall satisfy the requirements of an output
|
| 2074 |
+
iterator ([[output.iterators]]). Moreover, the expression `*dest = rt`
|
| 2075 |
+
shall be valid for a value `rt` of type `result_type`.
|
|
|
|
| 2076 |
|
| 2077 |
*Effects:* Copies the sequence of prepared 32-bit units to the given
|
| 2078 |
destination, as if by executing the following statement:
|
| 2079 |
|
| 2080 |
``` cpp
|
|
|
|
| 2085 |
|
| 2086 |
#### Function template `generate_canonical` <a id="rand.util.canonical">[[rand.util.canonical]]</a>
|
| 2087 |
|
| 2088 |
Each function instantiated from the template described in this section
|
| 2089 |
[[rand.util.canonical]] maps the result of one or more invocations of a
|
| 2090 |
+
supplied uniform random bit generator `g` to one member of the specified
|
| 2091 |
+
`RealType` such that, if the values gᵢ produced by `g` are uniformly
|
| 2092 |
+
distributed, the instantiation’s results tⱼ, 0 ≤ tⱼ < 1, are distributed
|
| 2093 |
+
as uniformly as possible as specified below.
|
| 2094 |
|
| 2095 |
+
[*Note 1*: Obtaining a value in this way can be a useful step in the
|
| 2096 |
+
process of transforming a value generated by a uniform random bit
|
| 2097 |
+
generator into a value that can be delivered by a random number
|
| 2098 |
+
distribution. — *end note*]
|
| 2099 |
|
| 2100 |
``` cpp
|
| 2101 |
+
template<class RealType, size_t bits, class URBG>
|
| 2102 |
+
RealType generate_canonical(URBG& g);
|
| 2103 |
```
|
| 2104 |
|
| 2105 |
*Complexity:* Exactly k = max(1, ⌈ b / log₂ R ⌉) invocations of `g`,
|
| 2106 |
where b[^5] is the lesser of `numeric_limits<RealType>::digits` and
|
| 2107 |
`bits`, and R is the value of `g.max()` - `g.min()` + 1.
|
|
|
|
| 2129 |
particular, declarations for copy constructors, for copy assignment
|
| 2130 |
operators, for streaming operators, and for equality and inequality
|
| 2131 |
operators are not shown in the synopses.
|
| 2132 |
|
| 2133 |
The algorithms for producing each of the specified distributions are
|
| 2134 |
+
*implementation-defined*.
|
| 2135 |
|
| 2136 |
The value of each probability density function p(z) and of each discrete
|
| 2137 |
probability function P(zᵢ) specified in this section is 0 everywhere
|
| 2138 |
outside its stated domain.
|
| 2139 |
|
|
|
|
| 2147 |
P(i\,|\,a,b) = 1 / (b - a + 1)
|
| 2148 |
\; \mbox{.}$$
|
| 2149 |
|
| 2150 |
``` cpp
|
| 2151 |
template<class IntType = int>
|
| 2152 |
+
class uniform_int_distribution {
|
|
|
|
| 2153 |
public:
|
| 2154 |
// types
|
| 2155 |
+
using result_type = IntType;
|
| 2156 |
+
using param_type = unspecified;
|
| 2157 |
|
| 2158 |
// constructors and reset functions
|
| 2159 |
explicit uniform_int_distribution(IntType a = 0, IntType b = numeric_limits<IntType>::max());
|
| 2160 |
explicit uniform_int_distribution(const param_type& parm);
|
| 2161 |
void reset();
|
| 2162 |
|
| 2163 |
// generating functions
|
| 2164 |
+
template<class URBG>
|
| 2165 |
+
result_type operator()(URBG& g);
|
| 2166 |
+
template<class URBG>
|
| 2167 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2168 |
|
| 2169 |
// property functions
|
| 2170 |
result_type a() const;
|
| 2171 |
result_type b() const;
|
| 2172 |
param_type param() const;
|
|
|
|
| 2205 |
numbers x, a ≤ x < b, distributed according to the constant probability
|
| 2206 |
density function $$%
|
| 2207 |
p(x\,|\,a,b) = 1 / (b - a)
|
| 2208 |
\; \mbox{.}$$
|
| 2209 |
|
| 2210 |
+
[*Note 1*: This implies that p(x | a,b) is undefined when
|
| 2211 |
+
`a == b`. — *end note*]
|
| 2212 |
+
|
| 2213 |
``` cpp
|
| 2214 |
template<class RealType = double>
|
| 2215 |
+
class uniform_real_distribution {
|
|
|
|
| 2216 |
public:
|
| 2217 |
// types
|
| 2218 |
+
using result_type = RealType;
|
| 2219 |
+
using param_type = unspecified;
|
| 2220 |
|
| 2221 |
// constructors and reset functions
|
| 2222 |
explicit uniform_real_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 2223 |
explicit uniform_real_distribution(const param_type& parm);
|
| 2224 |
void reset();
|
| 2225 |
|
| 2226 |
// generating functions
|
| 2227 |
+
template<class URBG>
|
| 2228 |
+
result_type operator()(URBG& g);
|
| 2229 |
+
template<class URBG>
|
| 2230 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2231 |
|
| 2232 |
// property functions
|
| 2233 |
result_type a() const;
|
| 2234 |
result_type b() const;
|
| 2235 |
param_type param() const;
|
|
|
|
| 2274 |
1-p & \mbox{if} & b = \tcode{false}
|
| 2275 |
\end{array}\right.
|
| 2276 |
\; \mbox{.}$$
|
| 2277 |
|
| 2278 |
``` cpp
|
| 2279 |
+
class bernoulli_distribution {
|
|
|
|
| 2280 |
public:
|
| 2281 |
// types
|
| 2282 |
+
using result_type = bool;
|
| 2283 |
+
using param_type = unspecified;
|
| 2284 |
|
| 2285 |
// constructors and reset functions
|
| 2286 |
explicit bernoulli_distribution(double p = 0.5);
|
| 2287 |
explicit bernoulli_distribution(const param_type& parm);
|
| 2288 |
void reset();
|
| 2289 |
|
| 2290 |
// generating functions
|
| 2291 |
+
template<class URBG>
|
| 2292 |
+
result_type operator()(URBG& g);
|
| 2293 |
+
template<class URBG>
|
| 2294 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2295 |
|
| 2296 |
// property functions
|
| 2297 |
double p() const;
|
| 2298 |
param_type param() const;
|
| 2299 |
void param(const param_type& parm);
|
|
|
|
| 2327 |
= \binom{t}{i} \cdot p^i \cdot (1-p)^{t-i}
|
| 2328 |
\; \mbox{.}$$
|
| 2329 |
|
| 2330 |
``` cpp
|
| 2331 |
template<class IntType = int>
|
| 2332 |
+
class binomial_distribution {
|
|
|
|
| 2333 |
public:
|
| 2334 |
// types
|
| 2335 |
+
using result_type = IntType;
|
| 2336 |
+
using param_type = unspecified;
|
| 2337 |
|
| 2338 |
// constructors and reset functions
|
| 2339 |
explicit binomial_distribution(IntType t = 1, double p = 0.5);
|
| 2340 |
explicit binomial_distribution(const param_type& parm);
|
| 2341 |
void reset();
|
| 2342 |
|
| 2343 |
// generating functions
|
| 2344 |
+
template<class URBG>
|
| 2345 |
+
result_type operator()(URBG& g);
|
| 2346 |
+
template<class URBG>
|
| 2347 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2348 |
|
| 2349 |
// property functions
|
| 2350 |
IntType t() const;
|
| 2351 |
double p() const;
|
| 2352 |
param_type param() const;
|
|
|
|
| 2388 |
= p \cdot (1-p)^{i}
|
| 2389 |
\; \mbox{.}$$
|
| 2390 |
|
| 2391 |
``` cpp
|
| 2392 |
template<class IntType = int>
|
| 2393 |
+
class geometric_distribution {
|
|
|
|
| 2394 |
public:
|
| 2395 |
// types
|
| 2396 |
+
using result_type = IntType;
|
| 2397 |
+
using param_type = unspecified;
|
| 2398 |
|
| 2399 |
// constructors and reset functions
|
| 2400 |
explicit geometric_distribution(double p = 0.5);
|
| 2401 |
explicit geometric_distribution(const param_type& parm);
|
| 2402 |
void reset();
|
| 2403 |
|
| 2404 |
// generating functions
|
| 2405 |
+
template<class URBG>
|
| 2406 |
+
result_type operator()(URBG& g);
|
| 2407 |
+
template<class URBG>
|
| 2408 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2409 |
|
| 2410 |
// property functions
|
| 2411 |
double p() const;
|
| 2412 |
param_type param() const;
|
| 2413 |
void param(const param_type& parm);
|
|
|
|
| 2439 |
function $$%
|
| 2440 |
P(i\,|\,k,p)
|
| 2441 |
= \binom{k+i-1}{i} \cdot p^k \cdot (1-p)^i
|
| 2442 |
\; \mbox{.}$$
|
| 2443 |
|
| 2444 |
+
[*Note 1*: This implies that P(i | k,p) is undefined when
|
| 2445 |
+
`p == 1`. — *end note*]
|
| 2446 |
+
|
| 2447 |
``` cpp
|
| 2448 |
template<class IntType = int>
|
| 2449 |
+
class negative_binomial_distribution {
|
|
|
|
| 2450 |
public:
|
| 2451 |
// types
|
| 2452 |
+
using result_type = IntType;
|
| 2453 |
+
using param_type = unspecified;
|
| 2454 |
|
| 2455 |
// constructor and reset functions
|
| 2456 |
explicit negative_binomial_distribution(IntType k = 1, double p = 0.5);
|
| 2457 |
explicit negative_binomial_distribution(const param_type& parm);
|
| 2458 |
void reset();
|
| 2459 |
|
| 2460 |
// generating functions
|
| 2461 |
+
template<class URBG>
|
| 2462 |
+
result_type operator()(URBG& g);
|
| 2463 |
+
template<class URBG>
|
| 2464 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2465 |
|
| 2466 |
// property functions
|
| 2467 |
IntType k() const;
|
| 2468 |
double p() const;
|
| 2469 |
param_type param() const;
|
|
|
|
| 2513 |
template<class IntType = int>
|
| 2514 |
class poisson_distribution
|
| 2515 |
{
|
| 2516 |
public:
|
| 2517 |
// types
|
| 2518 |
+
using result_type = IntType;
|
| 2519 |
+
using param_type = unspecified;
|
| 2520 |
|
| 2521 |
// constructors and reset functions
|
| 2522 |
explicit poisson_distribution(double mean = 1.0);
|
| 2523 |
explicit poisson_distribution(const param_type& parm);
|
| 2524 |
void reset();
|
| 2525 |
|
| 2526 |
// generating functions
|
| 2527 |
+
template<class URBG>
|
| 2528 |
+
result_type operator()(URBG& g);
|
| 2529 |
+
template<class URBG>
|
| 2530 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2531 |
|
| 2532 |
// property functions
|
| 2533 |
double mean() const;
|
| 2534 |
param_type param() const;
|
| 2535 |
void param(const param_type& parm);
|
|
|
|
| 2563 |
= \lambda e^{-\lambda x}
|
| 2564 |
\; \mbox{.}$$
|
| 2565 |
|
| 2566 |
``` cpp
|
| 2567 |
template<class RealType = double>
|
| 2568 |
+
class exponential_distribution {
|
|
|
|
| 2569 |
public:
|
| 2570 |
// types
|
| 2571 |
+
using result_type = RealType;
|
| 2572 |
+
using param_type = unspecified;
|
| 2573 |
|
| 2574 |
// constructors and reset functions
|
| 2575 |
explicit exponential_distribution(RealType lambda = 1.0);
|
| 2576 |
explicit exponential_distribution(const param_type& parm);
|
| 2577 |
void reset();
|
| 2578 |
|
| 2579 |
// generating functions
|
| 2580 |
+
template<class URBG>
|
| 2581 |
+
result_type operator()(URBG& g);
|
| 2582 |
+
template<class URBG>
|
| 2583 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2584 |
|
| 2585 |
// property functions
|
| 2586 |
RealType lambda() const;
|
| 2587 |
param_type param() const;
|
| 2588 |
void param(const param_type& parm);
|
|
|
|
| 2595 |
explicit exponential_distribution(RealType lambda = 1.0);
|
| 2596 |
```
|
| 2597 |
|
| 2598 |
*Requires:* 0 < `lambda`.
|
| 2599 |
|
| 2600 |
+
*Effects:* Constructs an `exponential_distribution` object; `lambda`
|
| 2601 |
corresponds to the parameter of the distribution.
|
| 2602 |
|
| 2603 |
``` cpp
|
| 2604 |
RealType lambda() const;
|
| 2605 |
```
|
|
|
|
| 2617 |
\, \cdot \, x^{\, \alpha-1}
|
| 2618 |
\; \mbox{.}$$
|
| 2619 |
|
| 2620 |
``` cpp
|
| 2621 |
template<class RealType = double>
|
| 2622 |
+
class gamma_distribution {
|
|
|
|
| 2623 |
public:
|
| 2624 |
// types
|
| 2625 |
+
using result_type = RealType;
|
| 2626 |
+
using param_type = unspecified;
|
| 2627 |
|
| 2628 |
// constructors and reset functions
|
| 2629 |
explicit gamma_distribution(RealType alpha = 1.0, RealType beta = 1.0);
|
| 2630 |
explicit gamma_distribution(const param_type& parm);
|
| 2631 |
void reset();
|
| 2632 |
|
| 2633 |
// generating functions
|
| 2634 |
+
template<class URBG>
|
| 2635 |
+
result_type operator()(URBG& g);
|
| 2636 |
+
template<class URBG>
|
| 2637 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2638 |
|
| 2639 |
// property functions
|
| 2640 |
RealType alpha() const;
|
| 2641 |
RealType beta() const;
|
| 2642 |
param_type param() const;
|
|
|
|
| 2680 |
\cdot \, \exp\left( -\left(\frac{x}{b}\right)^a\right)
|
| 2681 |
\; \mbox{.}$$
|
| 2682 |
|
| 2683 |
``` cpp
|
| 2684 |
template<class RealType = double>
|
| 2685 |
+
class weibull_distribution {
|
|
|
|
| 2686 |
public:
|
| 2687 |
// types
|
| 2688 |
+
using result_type = RealType;
|
| 2689 |
+
using param_type = unspecified;
|
| 2690 |
|
| 2691 |
// constructor and reset functions
|
| 2692 |
explicit weibull_distribution(RealType a = 1.0, RealType b = 1.0);
|
| 2693 |
explicit weibull_distribution(const param_type& parm);
|
| 2694 |
void reset();
|
| 2695 |
|
| 2696 |
// generating functions
|
| 2697 |
+
template<class URBG>
|
| 2698 |
+
result_type operator()(URBG& g);
|
| 2699 |
+
template<class URBG>
|
| 2700 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2701 |
|
| 2702 |
// property functions
|
| 2703 |
RealType a() const;
|
| 2704 |
RealType b() const;
|
| 2705 |
param_type param() const;
|
|
|
|
| 2744 |
\right)
|
| 2745 |
\; \mbox{.}$$
|
| 2746 |
|
| 2747 |
``` cpp
|
| 2748 |
template<class RealType = double>
|
| 2749 |
+
class extreme_value_distribution {
|
|
|
|
| 2750 |
public:
|
| 2751 |
// types
|
| 2752 |
+
using result_type = RealType;
|
| 2753 |
+
using param_type = unspecified;
|
| 2754 |
|
| 2755 |
// constructor and reset functions
|
| 2756 |
explicit extreme_value_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 2757 |
explicit extreme_value_distribution(const param_type& parm);
|
| 2758 |
void reset();
|
| 2759 |
|
| 2760 |
// generating functions
|
| 2761 |
+
template<class URBG>
|
| 2762 |
+
result_type operator()(URBG& g);
|
| 2763 |
+
template<class URBG>
|
| 2764 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2765 |
|
| 2766 |
// property functions
|
| 2767 |
RealType a() const;
|
| 2768 |
RealType b() const;
|
| 2769 |
param_type param() const;
|
|
|
|
| 2813 |
\; \mbox{.}$$ The distribution parameters μ and σ are also known as this
|
| 2814 |
distribution’s *mean* and *standard deviation* .
|
| 2815 |
|
| 2816 |
``` cpp
|
| 2817 |
template<class RealType = double>
|
| 2818 |
+
class normal_distribution {
|
|
|
|
| 2819 |
public:
|
| 2820 |
// types
|
| 2821 |
+
using result_type = RealType;
|
| 2822 |
+
using param_type = unspecified;
|
| 2823 |
|
| 2824 |
// constructors and reset functions
|
| 2825 |
explicit normal_distribution(RealType mean = 0.0, RealType stddev = 1.0);
|
| 2826 |
explicit normal_distribution(const param_type& parm);
|
| 2827 |
void reset();
|
| 2828 |
|
| 2829 |
// generating functions
|
| 2830 |
+
template<class URBG>
|
| 2831 |
+
result_type operator()(URBG& g);
|
| 2832 |
+
template<class URBG>
|
| 2833 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2834 |
|
| 2835 |
// property functions
|
| 2836 |
RealType mean() const;
|
| 2837 |
RealType stddev() const;
|
| 2838 |
param_type param() const;
|
|
|
|
| 2880 |
}
|
| 2881 |
\; \mbox{.}$$
|
| 2882 |
|
| 2883 |
``` cpp
|
| 2884 |
template<class RealType = double>
|
| 2885 |
+
class lognormal_distribution {
|
|
|
|
| 2886 |
public:
|
| 2887 |
// types
|
| 2888 |
+
using result_type = RealType;
|
| 2889 |
+
using param_type = unspecified;
|
| 2890 |
|
| 2891 |
// constructor and reset functions
|
| 2892 |
explicit lognormal_distribution(RealType m = 0.0, RealType s = 1.0);
|
| 2893 |
explicit lognormal_distribution(const param_type& parm);
|
| 2894 |
void reset();
|
| 2895 |
|
| 2896 |
// generating functions
|
| 2897 |
+
template<class URBG>
|
| 2898 |
+
result_type operator()(URBG& g);
|
| 2899 |
+
template<class URBG>
|
| 2900 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2901 |
|
| 2902 |
// property functions
|
| 2903 |
RealType m() const;
|
| 2904 |
RealType s() const;
|
| 2905 |
param_type param() const;
|
|
|
|
| 2942 |
{\Gamma(n/2) \cdot 2^{n/2}}
|
| 2943 |
\; \mbox{.}$$
|
| 2944 |
|
| 2945 |
``` cpp
|
| 2946 |
template<class RealType = double>
|
| 2947 |
+
class chi_squared_distribution {
|
|
|
|
| 2948 |
public:
|
| 2949 |
// types
|
| 2950 |
+
using result_type = RealType;
|
| 2951 |
+
using param_type = unspecified;
|
| 2952 |
|
| 2953 |
// constructor and reset functions
|
| 2954 |
explicit chi_squared_distribution(RealType n = 1);
|
| 2955 |
explicit chi_squared_distribution(const param_type& parm);
|
| 2956 |
void reset();
|
| 2957 |
|
| 2958 |
// generating functions
|
| 2959 |
+
template<class URBG>
|
| 2960 |
+
result_type operator()(URBG& g);
|
| 2961 |
+
template<class URBG>
|
| 2962 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 2963 |
|
| 2964 |
// property functions
|
| 2965 |
RealType n() const;
|
| 2966 |
param_type param() const;
|
| 2967 |
void param(const param_type& parm);
|
|
|
|
| 2994 |
= \left( \pi b \left( 1 + \left( \frac{x-a}{b} \right)^2 \;\right)\right)^{-1}
|
| 2995 |
\; \mbox{.}$$
|
| 2996 |
|
| 2997 |
``` cpp
|
| 2998 |
template<class RealType = double>
|
| 2999 |
+
class cauchy_distribution {
|
|
|
|
| 3000 |
public:
|
| 3001 |
// types
|
| 3002 |
+
using result_type = RealType;
|
| 3003 |
+
using param_type = unspecified;
|
| 3004 |
|
| 3005 |
// constructor and reset functions
|
| 3006 |
explicit cauchy_distribution(RealType a = 0.0, RealType b = 1.0);
|
| 3007 |
explicit cauchy_distribution(const param_type& parm);
|
| 3008 |
void reset();
|
| 3009 |
|
| 3010 |
// generating functions
|
| 3011 |
+
template<class URBG>
|
| 3012 |
+
result_type operator()(URBG& g);
|
| 3013 |
+
template<class URBG>
|
| 3014 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3015 |
|
| 3016 |
// property functions
|
| 3017 |
RealType a() const;
|
| 3018 |
RealType b() const;
|
| 3019 |
param_type param() const;
|
|
|
|
| 3062 |
{\left( 1 + \frac{m x}{n} \right)}^{-(m+n)/2}
|
| 3063 |
\; \mbox{.}$$
|
| 3064 |
|
| 3065 |
``` cpp
|
| 3066 |
template<class RealType = double>
|
| 3067 |
+
class fisher_f_distribution {
|
|
|
|
| 3068 |
public:
|
| 3069 |
// types
|
| 3070 |
+
using result_type = RealType;
|
| 3071 |
+
using param_type = unspecified;
|
| 3072 |
|
| 3073 |
// constructor and reset functions
|
| 3074 |
explicit fisher_f_distribution(RealType m = 1, RealType n = 1);
|
| 3075 |
explicit fisher_f_distribution(const param_type& parm);
|
| 3076 |
void reset();
|
| 3077 |
|
| 3078 |
// generating functions
|
| 3079 |
+
template<class URBG>
|
| 3080 |
+
result_type operator()(URBG& g);
|
| 3081 |
+
template<class URBG>
|
| 3082 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3083 |
|
| 3084 |
// property functions
|
| 3085 |
RealType m() const;
|
| 3086 |
RealType n() const;
|
| 3087 |
param_type param() const;
|
|
|
|
| 3126 |
\cdot \left( 1+\frac{x^2}{n} \right) ^ {-(n+1)/2}
|
| 3127 |
\; \mbox{.}$$
|
| 3128 |
|
| 3129 |
``` cpp
|
| 3130 |
template<class RealType = double>
|
| 3131 |
+
class student_t_distribution {
|
|
|
|
| 3132 |
public:
|
| 3133 |
// types
|
| 3134 |
+
using result_type = RealType;
|
| 3135 |
+
using param_type = unspecified;
|
| 3136 |
|
| 3137 |
// constructor and reset functions
|
| 3138 |
explicit student_t_distribution(RealType n = 1);
|
| 3139 |
explicit student_t_distribution(const param_type& parm);
|
| 3140 |
void reset();
|
| 3141 |
|
| 3142 |
// generating functions
|
| 3143 |
+
template<class URBG>
|
| 3144 |
+
result_type operator()(URBG& g);
|
| 3145 |
+
template<class URBG>
|
| 3146 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3147 |
|
| 3148 |
// property functions
|
| 3149 |
RealType n() const;
|
| 3150 |
param_type param() const;
|
| 3151 |
void param(const param_type& parm);
|
|
|
|
| 3187 |
non-NaN, and non-infinity. Moreover, the following relation shall hold:
|
| 3188 |
0 < S = w₀ + ⋯ + wₙ₋₁.
|
| 3189 |
|
| 3190 |
``` cpp
|
| 3191 |
template<class IntType = int>
|
| 3192 |
+
class discrete_distribution {
|
|
|
|
| 3193 |
public:
|
| 3194 |
// types
|
| 3195 |
+
using result_type = IntType;
|
| 3196 |
+
using param_type = unspecified;
|
| 3197 |
|
| 3198 |
// constructor and reset functions
|
| 3199 |
discrete_distribution();
|
| 3200 |
template<class InputIterator>
|
| 3201 |
discrete_distribution(InputIterator firstW, InputIterator lastW);
|
|
|
|
| 3204 |
discrete_distribution(size_t nw, double xmin, double xmax, UnaryOperation fw);
|
| 3205 |
explicit discrete_distribution(const param_type& parm);
|
| 3206 |
void reset();
|
| 3207 |
|
| 3208 |
// generating functions
|
| 3209 |
+
template<class URBG>
|
| 3210 |
+
result_type operator()(URBG& g);
|
| 3211 |
+
template<class URBG>
|
| 3212 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3213 |
|
| 3214 |
// property functions
|
| 3215 |
vector<double> probabilities() const;
|
| 3216 |
param_type param() const;
|
| 3217 |
void param(const param_type& parm);
|
|
|
|
| 3223 |
``` cpp
|
| 3224 |
discrete_distribution();
|
| 3225 |
```
|
| 3226 |
|
| 3227 |
*Effects:* Constructs a `discrete_distribution` object with n = 1 and
|
| 3228 |
+
p₀ = 1.
|
| 3229 |
+
|
| 3230 |
+
[*Note 1*: Such an object will always deliver the value
|
| 3231 |
+
0. — *end note*]
|
| 3232 |
|
| 3233 |
``` cpp
|
| 3234 |
template<class InputIterator>
|
| 3235 |
discrete_distribution(InputIterator firstW, InputIterator lastW);
|
| 3236 |
```
|
| 3237 |
|
| 3238 |
*Requires:* `InputIterator` shall satisfy the requirements of an input
|
| 3239 |
+
iterator ([[input.iterators]]). Moreover,
|
| 3240 |
`iterator_traits<InputIterator>::value_type` shall denote a type that is
|
| 3241 |
convertible to `double`. If `firstW == lastW`, let n = 1 and w₀ = 1.
|
| 3242 |
Otherwise, [`firstW`, `lastW`) shall form a sequence w of length n > 0.
|
| 3243 |
|
| 3244 |
*Effects:* Constructs a `discrete_distribution` object with
|
|
|
|
| 3299 |
non-infinity. Moreover, the following relation shall hold:
|
| 3300 |
0 < S = w₀ + ⋯ + wₙ₋₁.
|
| 3301 |
|
| 3302 |
``` cpp
|
| 3303 |
template<class RealType = double>
|
| 3304 |
+
class piecewise_constant_distribution {
|
|
|
|
| 3305 |
public:
|
| 3306 |
// types
|
| 3307 |
+
using result_type = RealType;
|
| 3308 |
+
using param_type = unspecified;
|
| 3309 |
|
| 3310 |
// constructor and reset functions
|
| 3311 |
piecewise_constant_distribution();
|
| 3312 |
template<class InputIteratorB, class InputIteratorW>
|
| 3313 |
piecewise_constant_distribution(InputIteratorB firstB, InputIteratorB lastB,
|
| 3314 |
InputIteratorW firstW);
|
| 3315 |
template<class UnaryOperation>
|
| 3316 |
piecewise_constant_distribution(initializer_list<RealType> bl, UnaryOperation fw);
|
| 3317 |
template<class UnaryOperation>
|
| 3318 |
+
piecewise_constant_distribution(size_t nw, RealType xmin, RealType xmax,
|
| 3319 |
+
UnaryOperation fw);
|
| 3320 |
explicit piecewise_constant_distribution(const param_type& parm);
|
| 3321 |
void reset();
|
| 3322 |
|
| 3323 |
// generating functions
|
| 3324 |
+
template<class URBG>
|
| 3325 |
+
result_type operator()(URBG& g);
|
| 3326 |
+
template<class URBG>
|
| 3327 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3328 |
|
| 3329 |
// property functions
|
| 3330 |
vector<result_type> intervals() const;
|
| 3331 |
vector<result_type> densities() const;
|
| 3332 |
param_type param() const;
|
|
|
|
| 3439 |
\cdot \sum_{k=0}^{n-1} (w_k + w_{k+1}) \cdot (b_{k+1} - b_k)
|
| 3440 |
\; \mbox{.}$$
|
| 3441 |
|
| 3442 |
``` cpp
|
| 3443 |
template<class RealType = double>
|
| 3444 |
+
class piecewise_linear_distribution {
|
|
|
|
| 3445 |
public:
|
| 3446 |
// types
|
| 3447 |
+
using result_type = RealType;
|
| 3448 |
+
using param_type = unspecified;
|
| 3449 |
|
| 3450 |
// constructor and reset functions
|
| 3451 |
piecewise_linear_distribution();
|
| 3452 |
template<class InputIteratorB, class InputIteratorW>
|
| 3453 |
piecewise_linear_distribution(InputIteratorB firstB, InputIteratorB lastB,
|
|
|
|
| 3458 |
piecewise_linear_distribution(size_t nw, RealType xmin, RealType xmax, UnaryOperation fw);
|
| 3459 |
explicit piecewise_linear_distribution(const param_type& parm);
|
| 3460 |
void reset();
|
| 3461 |
|
| 3462 |
// generating functions
|
| 3463 |
+
template<class URBG>
|
| 3464 |
+
result_type operator()(URBG& g);
|
| 3465 |
+
template<class URBG>
|
| 3466 |
+
result_type operator()(URBG& g, const param_type& parm);
|
| 3467 |
|
| 3468 |
// property functions
|
| 3469 |
vector<result_type> intervals() const;
|
| 3470 |
vector<result_type> densities() const;
|
| 3471 |
param_type param() const;
|
|
|
|
| 3551 |
|
| 3552 |
*Returns:* A `vector<result_type>` whose `size` member returns n and
|
| 3553 |
whose `operator[]` member returns ρₖ when invoked with argument k for
|
| 3554 |
k = 0, …, n.
|
| 3555 |
|
| 3556 |
+
### Low-quality random number generation <a id="c.math.rand">[[c.math.rand]]</a>
|
| 3557 |
+
|
| 3558 |
+
[*Note 1*: The header `<cstdlib>` ([[cstdlib.syn]]) declares the
|
| 3559 |
+
functions described in this subclause. — *end note*]
|
| 3560 |
+
|
| 3561 |
+
``` cpp
|
| 3562 |
+
int rand();
|
| 3563 |
+
void srand(unsigned int seed);
|
| 3564 |
+
```
|
| 3565 |
+
|
| 3566 |
+
*Effects:* The `rand` and `srand` functions have the semantics specified
|
| 3567 |
+
in the C standard library.
|
| 3568 |
+
|
| 3569 |
+
*Remarks:* The implementation may specify that particular library
|
| 3570 |
+
functions may call `rand`. It is *implementation-defined* whether the
|
| 3571 |
+
`rand` function may introduce data races ([[res.on.data.races]]).
|
| 3572 |
+
|
| 3573 |
+
[*Note 1*: The other random number generation facilities in this
|
| 3574 |
+
International Standard ([[rand]]) are often preferable to `rand`,
|
| 3575 |
+
because `rand`’s underlying algorithm is unspecified. Use of `rand`
|
| 3576 |
+
therefore continues to be non-portable, with unpredictable and
|
| 3577 |
+
oft-questionable quality and performance. — *end note*]
|
| 3578 |
+
|
| 3579 |
+
ISO C 7.22.2
|
| 3580 |
+
|
| 3581 |
## Numeric arrays <a id="numarray">[[numarray]]</a>
|
| 3582 |
|
| 3583 |
### Header `<valarray>` synopsis <a id="valarray.syn">[[valarray.syn]]</a>
|
| 3584 |
|
| 3585 |
``` cpp
|
| 3586 |
#include <initializer_list>
|
| 3587 |
|
| 3588 |
namespace std {
|
|
|
|
| 3589 |
template<class T> class valarray; // An array of type T
|
| 3590 |
class slice; // a BLAS-like slice out of an array
|
| 3591 |
template<class T> class slice_array;
|
| 3592 |
class gslice; // a generalized slice out of an array
|
| 3593 |
template<class T> class gslice_array;
|
|
|
|
| 3726 |
identical functions taking every combination of `const valarray<T>&`
|
| 3727 |
and replacement types shall be added.
|
| 3728 |
|
| 3729 |
In particular, an implementation shall allow a `valarray<T>` to be
|
| 3730 |
constructed from such replacement types and shall allow assignments and
|
| 3731 |
+
compound assignments of such types to `valarray<T>`, `slice_array<T>`,
|
| 3732 |
`gslice_array<T>`, `mask_array<T>` and `indirect_array<T>` objects.
|
| 3733 |
|
| 3734 |
These library functions are permitted to throw a `bad_alloc` (
|
| 3735 |
[[bad.alloc]]) exception if there are not sufficient resources available
|
| 3736 |
to carry out the operation. Note that the exception is not mandated.
|
|
|
|
| 3741 |
|
| 3742 |
``` cpp
|
| 3743 |
namespace std {
|
| 3744 |
template<class T> class valarray {
|
| 3745 |
public:
|
| 3746 |
+
using value_type = T;
|
| 3747 |
|
| 3748 |
+
// [valarray.cons], construct/destroy
|
| 3749 |
valarray();
|
| 3750 |
explicit valarray(size_t);
|
| 3751 |
valarray(const T&, size_t);
|
| 3752 |
valarray(const T*, size_t);
|
| 3753 |
valarray(const valarray&);
|
|
|
|
| 3757 |
valarray(const mask_array<T>&);
|
| 3758 |
valarray(const indirect_array<T>&);
|
| 3759 |
valarray(initializer_list<T>);
|
| 3760 |
~valarray();
|
| 3761 |
|
| 3762 |
+
// [valarray.assign], assignment
|
| 3763 |
+
valarray& operator=(const valarray&);
|
| 3764 |
+
valarray& operator=(valarray&&) noexcept;
|
| 3765 |
valarray& operator=(initializer_list<T>);
|
| 3766 |
+
valarray& operator=(const T&);
|
| 3767 |
+
valarray& operator=(const slice_array<T>&);
|
| 3768 |
+
valarray& operator=(const gslice_array<T>&);
|
| 3769 |
+
valarray& operator=(const mask_array<T>&);
|
| 3770 |
+
valarray& operator=(const indirect_array<T>&);
|
| 3771 |
|
| 3772 |
+
// [valarray.access], element access
|
| 3773 |
const T& operator[](size_t) const;
|
| 3774 |
T& operator[](size_t);
|
| 3775 |
|
| 3776 |
+
// [valarray.sub], subset operations
|
| 3777 |
+
valarray operator[](slice) const;
|
| 3778 |
slice_array<T> operator[](slice);
|
| 3779 |
+
valarray operator[](const gslice&) const;
|
| 3780 |
gslice_array<T> operator[](const gslice&);
|
| 3781 |
+
valarray operator[](const valarray<bool>&) const;
|
| 3782 |
mask_array<T> operator[](const valarray<bool>&);
|
| 3783 |
+
valarray operator[](const valarray<size_t>&) const;
|
| 3784 |
indirect_array<T> operator[](const valarray<size_t>&);
|
| 3785 |
|
| 3786 |
+
// [valarray.unary], unary operators
|
| 3787 |
+
valarray operator+() const;
|
| 3788 |
+
valarray operator-() const;
|
| 3789 |
+
valarray operator~() const;
|
| 3790 |
valarray<bool> operator!() const;
|
| 3791 |
|
| 3792 |
+
// [valarray.cassign], compound assignment
|
| 3793 |
+
valarray& operator*= (const T&);
|
| 3794 |
+
valarray& operator/= (const T&);
|
| 3795 |
+
valarray& operator%= (const T&);
|
| 3796 |
+
valarray& operator+= (const T&);
|
| 3797 |
+
valarray& operator-= (const T&);
|
| 3798 |
+
valarray& operator^= (const T&);
|
| 3799 |
+
valarray& operator&= (const T&);
|
| 3800 |
+
valarray& operator|= (const T&);
|
| 3801 |
+
valarray& operator<<=(const T&);
|
| 3802 |
+
valarray& operator>>=(const T&);
|
| 3803 |
|
| 3804 |
+
valarray& operator*= (const valarray&);
|
| 3805 |
+
valarray& operator/= (const valarray&);
|
| 3806 |
+
valarray& operator%= (const valarray&);
|
| 3807 |
+
valarray& operator+= (const valarray&);
|
| 3808 |
+
valarray& operator-= (const valarray&);
|
| 3809 |
+
valarray& operator^= (const valarray&);
|
| 3810 |
+
valarray& operator|= (const valarray&);
|
| 3811 |
+
valarray& operator&= (const valarray&);
|
| 3812 |
+
valarray& operator<<=(const valarray&);
|
| 3813 |
+
valarray& operator>>=(const valarray&);
|
| 3814 |
|
| 3815 |
+
// [valarray.members], member functions
|
| 3816 |
void swap(valarray&) noexcept;
|
| 3817 |
|
| 3818 |
size_t size() const;
|
| 3819 |
|
| 3820 |
T sum() const;
|
| 3821 |
T min() const;
|
| 3822 |
T max() const;
|
| 3823 |
|
| 3824 |
+
valarray shift (int) const;
|
| 3825 |
+
valarray cshift(int) const;
|
| 3826 |
+
valarray apply(T func(T)) const;
|
| 3827 |
+
valarray apply(T func(const T&)) const;
|
| 3828 |
void resize(size_t sz, T c = T());
|
| 3829 |
};
|
| 3830 |
+
|
| 3831 |
+
template<class T, size_t cnt> valarray(const T(&)[cnt], size_t) -> valarray<T>;
|
| 3832 |
}
|
| 3833 |
```
|
| 3834 |
|
| 3835 |
The class template `valarray<T>` is a one-dimensional smart array, with
|
| 3836 |
elements numbered sequentially from zero. It is a representation of the
|
| 3837 |
+
mathematical concept of an ordered set of values. For convenience, an
|
| 3838 |
+
object of type `valarray<T>` is referred to as an “array” throughout the
|
| 3839 |
+
remainder of [[numarray]]. The illusion of higher dimensionality may be
|
| 3840 |
+
produced by the familiar idiom of computed indices, together with the
|
| 3841 |
+
powerful subsetting capabilities provided by the generalized subscript
|
| 3842 |
+
operators.[^8]
|
| 3843 |
|
| 3844 |
An implementation is permitted to qualify any of the functions declared
|
| 3845 |
in `<valarray>` as `inline`.
|
| 3846 |
|
| 3847 |
#### `valarray` constructors <a id="valarray.cons">[[valarray.cons]]</a>
|
| 3848 |
|
| 3849 |
``` cpp
|
| 3850 |
valarray();
|
| 3851 |
```
|
| 3852 |
|
| 3853 |
+
*Effects:* Constructs a `valarray` that has zero length.[^9]
|
|
|
|
| 3854 |
|
| 3855 |
``` cpp
|
| 3856 |
+
explicit valarray(size_t n);
|
| 3857 |
```
|
| 3858 |
|
| 3859 |
+
*Effects:* Constructs a `valarray` that has length `n`. Each element of
|
| 3860 |
+
the array is value-initialized ([[dcl.init]]).
|
|
|
|
| 3861 |
|
| 3862 |
``` cpp
|
| 3863 |
+
valarray(const T& v, size_t n);
|
| 3864 |
```
|
| 3865 |
|
| 3866 |
+
*Effects:* Constructs a `valarray` that has length `n`. Each element of
|
| 3867 |
+
the array is initialized with `v`.
|
|
|
|
| 3868 |
|
| 3869 |
``` cpp
|
| 3870 |
+
valarray(const T* p, size_t n);
|
| 3871 |
```
|
| 3872 |
|
| 3873 |
+
*Requires:* `p` points to an array ([[dcl.array]]) of at least `n`
|
| 3874 |
+
elements.
|
| 3875 |
+
|
| 3876 |
+
*Effects:* Constructs a `valarray` that has length `n`. The values of
|
| 3877 |
+
the elements of the array are initialized with the first `n` values
|
| 3878 |
+
pointed to by the first argument.[^10]
|
| 3879 |
|
| 3880 |
``` cpp
|
| 3881 |
+
valarray(const valarray& v);
|
| 3882 |
```
|
| 3883 |
|
| 3884 |
+
*Effects:* Constructs a `valarray` that has the same length as `v`. The
|
| 3885 |
+
elements are initialized with the values of the corresponding elements
|
| 3886 |
+
of `v`.[^11]
|
| 3887 |
|
| 3888 |
``` cpp
|
| 3889 |
+
valarray(valarray&& v) noexcept;
|
| 3890 |
```
|
| 3891 |
|
| 3892 |
+
*Effects:* Constructs a `valarray` that has the same length as `v`. The
|
| 3893 |
+
elements are initialized with the values of the corresponding elements
|
| 3894 |
+
of `v`.
|
| 3895 |
|
| 3896 |
*Complexity:* Constant.
|
| 3897 |
|
| 3898 |
``` cpp
|
| 3899 |
valarray(initializer_list<T> il);
|
| 3900 |
```
|
| 3901 |
|
| 3902 |
+
*Effects:* Equivalent to `valarray(il.begin(), il.size())`.
|
| 3903 |
|
| 3904 |
``` cpp
|
| 3905 |
valarray(const slice_array<T>&);
|
| 3906 |
valarray(const gslice_array<T>&);
|
| 3907 |
valarray(const mask_array<T>&);
|
|
|
|
| 3913 |
|
| 3914 |
``` cpp
|
| 3915 |
~valarray();
|
| 3916 |
```
|
| 3917 |
|
| 3918 |
+
*Effects:* The destructor is applied to every element of `*this`; an
|
| 3919 |
+
implementation may return all allocated memory.
|
| 3920 |
|
| 3921 |
#### `valarray` assignment <a id="valarray.assign">[[valarray.assign]]</a>
|
| 3922 |
|
| 3923 |
``` cpp
|
| 3924 |
+
valarray& operator=(const valarray& v);
|
| 3925 |
```
|
| 3926 |
|
| 3927 |
+
*Effects:* Each element of the `*this` array is assigned the value of
|
| 3928 |
+
the corresponding element of `v`. If the length of `v` is not equal to
|
| 3929 |
+
the length of `*this`, resizes `*this` to make the two arrays the same
|
| 3930 |
+
length, as if by calling `resize(v.size())`, before performing the
|
| 3931 |
+
assignment.
|
| 3932 |
|
| 3933 |
+
*Postconditions:* `size() == v.size()`.
|
| 3934 |
+
|
| 3935 |
+
*Returns:* `*this`.
|
| 3936 |
|
| 3937 |
``` cpp
|
| 3938 |
+
valarray& operator=(valarray&& v) noexcept;
|
| 3939 |
```
|
| 3940 |
|
| 3941 |
*Effects:* `*this` obtains the value of `v`. The value of `v` after the
|
| 3942 |
assignment is not specified.
|
| 3943 |
|
| 3944 |
+
*Returns:* `*this`.
|
| 3945 |
+
|
| 3946 |
*Complexity:* Linear.
|
| 3947 |
|
| 3948 |
``` cpp
|
| 3949 |
valarray& operator=(initializer_list<T> il);
|
| 3950 |
```
|
| 3951 |
|
| 3952 |
+
*Effects:* Equivalent to: `return *this = valarray(il);`
|
|
|
|
|
|
|
| 3953 |
|
| 3954 |
``` cpp
|
| 3955 |
+
valarray& operator=(const T& v);
|
| 3956 |
```
|
| 3957 |
|
| 3958 |
+
*Effects:* Assigns `v` to each element of `*this`.
|
| 3959 |
+
|
| 3960 |
+
*Returns:* `*this`.
|
| 3961 |
|
| 3962 |
``` cpp
|
| 3963 |
+
valarray& operator=(const slice_array<T>&);
|
| 3964 |
+
valarray& operator=(const gslice_array<T>&);
|
| 3965 |
+
valarray& operator=(const mask_array<T>&);
|
| 3966 |
+
valarray& operator=(const indirect_array<T>&);
|
| 3967 |
```
|
| 3968 |
|
| 3969 |
*Requires:* The length of the array to which the argument refers equals
|
| 3970 |
+
`size()`. The value of an element in the left-hand side of a `valarray`
|
| 3971 |
+
assignment operator does not depend on the value of another element in
|
| 3972 |
+
that left-hand side.
|
| 3973 |
|
| 3974 |
These operators allow the results of a generalized subscripting
|
| 3975 |
operation to be assigned directly to a `valarray`.
|
| 3976 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| 3977 |
#### `valarray` element access <a id="valarray.access">[[valarray.access]]</a>
|
| 3978 |
|
| 3979 |
``` cpp
|
| 3980 |
+
const T& operator[](size_t n) const;
|
| 3981 |
+
T& operator[](size_t n);
|
| 3982 |
```
|
| 3983 |
|
| 3984 |
+
*Requires:* `n < size()`.
|
|
|
|
| 3985 |
|
| 3986 |
+
*Returns:* A reference to the corresponding element of the array.
|
|
|
|
|
|
|
| 3987 |
|
| 3988 |
+
[*Note 1*: The expression `(a[i] = q, a[i]) == q` evaluates to `true`
|
| 3989 |
+
for any non-constant `valarray<T> a`, any `T q`, and for any `size_t i`
|
| 3990 |
+
such that the value of `i` is less than the length of
|
| 3991 |
+
`a`. — *end note*]
|
| 3992 |
|
| 3993 |
+
*Remarks:* The expression `&a[i+j] == &a[i] + j` evaluates to `true` for
|
| 3994 |
+
all `size_t i` and `size_t j` such that `i+j < a.size()`.
|
| 3995 |
+
|
| 3996 |
+
The expression `&a[i] != &b[j]` evaluates to `true` for any two arrays
|
| 3997 |
+
`a` and `b` and for any `size_t i` and `size_t j` such that
|
| 3998 |
+
`i < a.size()` and `j < b.size()`.
|
| 3999 |
+
|
| 4000 |
+
[*Note 2*: This property indicates an absence of aliasing and may be
|
| 4001 |
+
used to advantage by optimizing compilers. Compilers may take advantage
|
| 4002 |
+
of inlining, constant propagation, loop fusion, tracking of pointers
|
| 4003 |
+
obtained from `operator new`, and other techniques to generate efficient
|
| 4004 |
+
`valarray`s. — *end note*]
|
| 4005 |
|
| 4006 |
The reference returned by the subscript operator for an array shall be
|
| 4007 |
valid until the member function
|
| 4008 |
`resize(size_t, T)` ([[valarray.members]]) is called for that array or
|
| 4009 |
until the lifetime of that array ends, whichever happens first.
|
| 4010 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| 4011 |
#### `valarray` subset operations <a id="valarray.sub">[[valarray.sub]]</a>
|
| 4012 |
|
| 4013 |
The member `operator[]` is overloaded to provide several ways to select
|
| 4014 |
sequences of elements from among those controlled by `*this`. Each of
|
| 4015 |
these operations returns a subset of the array. The const-qualified
|
|
|
|
| 4019 |
`operator=` and other assigning operators to allow selective replacement
|
| 4020 |
(slicing) of the controlled sequence. In each case the selected
|
| 4021 |
element(s) must exist.
|
| 4022 |
|
| 4023 |
``` cpp
|
| 4024 |
+
valarray operator[](slice slicearr) const;
|
| 4025 |
```
|
| 4026 |
|
| 4027 |
+
*Returns:* A `valarray` containing those elements of the controlled
|
| 4028 |
+
sequence designated by `slicearr`.
|
| 4029 |
+
|
| 4030 |
+
[*Example 1*:
|
| 4031 |
|
| 4032 |
``` cpp
|
| 4033 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4034 |
// v0[slice(2, 5, 3)] returns valarray<char>("cfilo", 5)
|
| 4035 |
```
|
| 4036 |
|
| 4037 |
+
— *end example*]
|
| 4038 |
+
|
| 4039 |
``` cpp
|
| 4040 |
slice_array<T> operator[](slice slicearr);
|
| 4041 |
```
|
| 4042 |
|
| 4043 |
*Returns:* An object that holds references to elements of the controlled
|
| 4044 |
sequence selected by `slicearr`.
|
| 4045 |
|
| 4046 |
+
[*Example 2*:
|
| 4047 |
+
|
| 4048 |
``` cpp
|
| 4049 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4050 |
valarray<char> v1("ABCDE", 5);
|
| 4051 |
v0[slice(2, 5, 3)] = v1;
|
| 4052 |
// v0 == valarray<char>("abAdeBghCjkDmnEp", 16);
|
| 4053 |
```
|
| 4054 |
|
| 4055 |
+
— *end example*]
|
| 4056 |
+
|
| 4057 |
``` cpp
|
| 4058 |
+
valarray operator[](const gslice& gslicearr) const;
|
| 4059 |
```
|
| 4060 |
|
| 4061 |
+
*Returns:* A `valarray` containing those elements of the controlled
|
| 4062 |
+
sequence designated by `gslicearr`.
|
| 4063 |
+
|
| 4064 |
+
[*Example 3*:
|
| 4065 |
|
| 4066 |
``` cpp
|
| 4067 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4068 |
const size_t lv[] = { 2, 3 };
|
| 4069 |
const size_t dv[] = { 7, 2 };
|
| 4070 |
const valarray<size_t> len(lv, 2), str(dv, 2);
|
| 4071 |
// v0[gslice(3, len, str)] returns
|
| 4072 |
// valarray<char>("dfhkmo", 6)
|
| 4073 |
```
|
| 4074 |
|
| 4075 |
+
— *end example*]
|
| 4076 |
+
|
| 4077 |
``` cpp
|
| 4078 |
gslice_array<T> operator[](const gslice& gslicearr);
|
| 4079 |
```
|
| 4080 |
|
| 4081 |
*Returns:* An object that holds references to elements of the controlled
|
| 4082 |
sequence selected by `gslicearr`.
|
| 4083 |
|
| 4084 |
+
[*Example 4*:
|
| 4085 |
+
|
| 4086 |
``` cpp
|
| 4087 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4088 |
+
valarray<char> v1("ABCDEF", 6);
|
| 4089 |
const size_t lv[] = { 2, 3 };
|
| 4090 |
const size_t dv[] = { 7, 2 };
|
| 4091 |
const valarray<size_t> len(lv, 2), str(dv, 2);
|
| 4092 |
v0[gslice(3, len, str)] = v1;
|
| 4093 |
// v0 == valarray<char>("abcAeBgCijDlEnFp", 16)
|
| 4094 |
```
|
| 4095 |
|
| 4096 |
+
— *end example*]
|
| 4097 |
+
|
| 4098 |
``` cpp
|
| 4099 |
+
valarray operator[](const valarray<bool>& boolarr) const;
|
| 4100 |
```
|
| 4101 |
|
| 4102 |
+
*Returns:* A `valarray` containing those elements of the controlled
|
| 4103 |
+
sequence designated by `boolarr`.
|
| 4104 |
+
|
| 4105 |
+
[*Example 5*:
|
| 4106 |
|
| 4107 |
``` cpp
|
| 4108 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4109 |
const bool vb[] = { false, false, true, true, false, true };
|
| 4110 |
// v0[valarray<bool>(vb, 6)] returns
|
| 4111 |
// valarray<char>("cdf", 3)
|
| 4112 |
```
|
| 4113 |
|
| 4114 |
+
— *end example*]
|
| 4115 |
+
|
| 4116 |
``` cpp
|
| 4117 |
mask_array<T> operator[](const valarray<bool>& boolarr);
|
| 4118 |
```
|
| 4119 |
|
| 4120 |
*Returns:* An object that holds references to elements of the controlled
|
| 4121 |
sequence selected by `boolarr`.
|
| 4122 |
|
| 4123 |
+
[*Example 6*:
|
| 4124 |
+
|
| 4125 |
``` cpp
|
| 4126 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4127 |
valarray<char> v1("ABC", 3);
|
| 4128 |
const bool vb[] = { false, false, true, true, false, true };
|
| 4129 |
v0[valarray<bool>(vb, 6)] = v1;
|
| 4130 |
// v0 == valarray<char>("abABeCghijklmnop", 16)
|
| 4131 |
```
|
| 4132 |
|
| 4133 |
+
— *end example*]
|
| 4134 |
+
|
| 4135 |
``` cpp
|
| 4136 |
+
valarray operator[](const valarray<size_t>& indarr) const;
|
| 4137 |
```
|
| 4138 |
|
| 4139 |
+
*Returns:* A `valarray` containing those elements of the controlled
|
| 4140 |
+
sequence designated by `indarr`.
|
| 4141 |
+
|
| 4142 |
+
[*Example 7*:
|
| 4143 |
|
| 4144 |
``` cpp
|
| 4145 |
const valarray<char> v0("abcdefghijklmnop", 16);
|
| 4146 |
const size_t vi[] = { 7, 5, 2, 3, 8 };
|
| 4147 |
// v0[valarray<size_t>(vi, 5)] returns
|
| 4148 |
// valarray<char>("hfcdi", 5)
|
| 4149 |
```
|
| 4150 |
|
| 4151 |
+
— *end example*]
|
| 4152 |
+
|
| 4153 |
``` cpp
|
| 4154 |
indirect_array<T> operator[](const valarray<size_t>& indarr);
|
| 4155 |
```
|
| 4156 |
|
| 4157 |
*Returns:* An object that holds references to elements of the controlled
|
| 4158 |
sequence selected by `indarr`.
|
| 4159 |
|
| 4160 |
+
[*Example 8*:
|
| 4161 |
+
|
| 4162 |
``` cpp
|
| 4163 |
valarray<char> v0("abcdefghijklmnop", 16);
|
| 4164 |
valarray<char> v1("ABCDE", 5);
|
| 4165 |
const size_t vi[] = { 7, 5, 2, 3, 8 };
|
| 4166 |
v0[valarray<size_t>(vi, 5)] = v1;
|
| 4167 |
// v0 == valarray<char>("abCDeBgAEjklmnop", 16)
|
| 4168 |
```
|
| 4169 |
|
| 4170 |
+
— *end example*]
|
| 4171 |
+
|
| 4172 |
#### `valarray` unary operators <a id="valarray.unary">[[valarray.unary]]</a>
|
| 4173 |
|
| 4174 |
``` cpp
|
| 4175 |
+
valarray operator+() const;
|
| 4176 |
+
valarray operator-() const;
|
| 4177 |
+
valarray operator~() const;
|
| 4178 |
valarray<bool> operator!() const;
|
| 4179 |
```
|
| 4180 |
|
| 4181 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4182 |
+
`T` to which the indicated operator can be applied and for which the
|
| 4183 |
+
indicated operator returns a value which is of type `T` (`bool` for
|
| 4184 |
+
`operator!`) or which may be unambiguously implicitly converted to type
|
| 4185 |
+
`T` (`bool` for `operator!`).
|
| 4186 |
|
| 4187 |
+
*Returns:* A `valarray` whose length is `size()`. Each element of the
|
| 4188 |
+
returned array is initialized with the result of applying the indicated
|
| 4189 |
+
operator to the corresponding element of the array.
|
|
|
|
| 4190 |
|
| 4191 |
+
#### `valarray` compound assignment <a id="valarray.cassign">[[valarray.cassign]]</a>
|
| 4192 |
|
| 4193 |
``` cpp
|
| 4194 |
+
valarray& operator*= (const valarray& v);
|
| 4195 |
+
valarray& operator/= (const valarray& v);
|
| 4196 |
+
valarray& operator%= (const valarray& v);
|
| 4197 |
+
valarray& operator+= (const valarray& v);
|
| 4198 |
+
valarray& operator-= (const valarray& v);
|
| 4199 |
+
valarray& operator^= (const valarray& v);
|
| 4200 |
+
valarray& operator&= (const valarray& v);
|
| 4201 |
+
valarray& operator|= (const valarray& v);
|
| 4202 |
+
valarray& operator<<=(const valarray& v);
|
| 4203 |
+
valarray& operator>>=(const valarray& v);
|
| 4204 |
```
|
| 4205 |
|
| 4206 |
+
*Requires:* `size() == v.size()`. Each of these operators may only be
|
| 4207 |
+
instantiated for a type `T` if the indicated operator can be applied to
|
| 4208 |
+
two operands of type `T`. The value of an element in the left-hand side
|
| 4209 |
+
of a valarray compound assignment operator does not depend on the value
|
| 4210 |
+
of another element in that left hand side.
|
| 4211 |
|
| 4212 |
+
*Effects:* Each of these operators performs the indicated operation on
|
| 4213 |
+
each of the elements of `*this` and the corresponding element of `v`.
|
| 4214 |
|
| 4215 |
+
*Returns:* `*this`.
|
|
|
|
|
|
|
| 4216 |
|
| 4217 |
+
*Remarks:* The appearance of an array on the left-hand side of a
|
| 4218 |
+
compound assignment does not invalidate references or pointers.
|
|
|
|
| 4219 |
|
| 4220 |
``` cpp
|
| 4221 |
+
valarray& operator*= (const T& v);
|
| 4222 |
+
valarray& operator/= (const T& v);
|
| 4223 |
+
valarray& operator%= (const T& v);
|
| 4224 |
+
valarray& operator+= (const T& v);
|
| 4225 |
+
valarray& operator-= (const T& v);
|
| 4226 |
+
valarray& operator^= (const T& v);
|
| 4227 |
+
valarray& operator&= (const T& v);
|
| 4228 |
+
valarray& operator|= (const T& v);
|
| 4229 |
+
valarray& operator<<=(const T& v);
|
| 4230 |
+
valarray& operator>>=(const T& v);
|
| 4231 |
```
|
| 4232 |
|
| 4233 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4234 |
+
`T` if the indicated operator can be applied to two operands of type
|
| 4235 |
+
`T`.
|
| 4236 |
|
| 4237 |
+
*Effects:* Each of these operators applies the indicated operation to
|
| 4238 |
+
each element of `*this` and `v`.
|
| 4239 |
|
| 4240 |
+
*Returns:* `*this`
|
| 4241 |
|
| 4242 |
+
*Remarks:* The appearance of an array on the left-hand side of a
|
| 4243 |
+
compound assignment does not invalidate references or pointers to the
|
| 4244 |
+
elements of the array.
|
| 4245 |
|
| 4246 |
#### `valarray` member functions <a id="valarray.members">[[valarray.members]]</a>
|
| 4247 |
|
| 4248 |
``` cpp
|
| 4249 |
void swap(valarray& v) noexcept;
|
|
|
|
| 4264 |
|
| 4265 |
``` cpp
|
| 4266 |
T sum() const;
|
| 4267 |
```
|
| 4268 |
|
| 4269 |
+
*Requires:* `size() > 0`. This function may only be instantiated for a
|
| 4270 |
+
type `T` to which `operator+=` can be applied.
|
|
|
|
| 4271 |
|
| 4272 |
+
*Returns:* The sum of all the elements of the array. If the array has
|
| 4273 |
+
length 1, returns the value of element 0. Otherwise, the returned value
|
| 4274 |
+
is calculated by applying `operator+=` to a copy of an element of the
|
| 4275 |
+
array and all other elements of the array in an unspecified order.
|
|
|
|
| 4276 |
|
| 4277 |
``` cpp
|
| 4278 |
T min() const;
|
| 4279 |
```
|
| 4280 |
|
| 4281 |
+
*Requires:* `size() > 0`
|
| 4282 |
+
|
| 4283 |
+
*Returns:* The minimum value contained in `*this`. For an array of
|
| 4284 |
+
length 1, the value of element 0 is returned. For all other array
|
| 4285 |
+
lengths, the determination is made using `operator<`.
|
| 4286 |
|
| 4287 |
``` cpp
|
| 4288 |
T max() const;
|
| 4289 |
```
|
| 4290 |
|
| 4291 |
+
*Requires:* `size() > 0`.
|
| 4292 |
+
|
| 4293 |
+
*Returns:* The maximum value contained in `*this`. For an array of
|
| 4294 |
+
length 1, the value of element 0 is returned. For all other array
|
| 4295 |
+
lengths, the determination is made using `operator<`.
|
| 4296 |
|
| 4297 |
``` cpp
|
| 4298 |
+
valarray shift(int n) const;
|
| 4299 |
```
|
| 4300 |
|
| 4301 |
+
*Returns:* A `valarray` of length `size()`, each of whose elements *I*
|
| 4302 |
+
is `(*this)[`*`I`*` + n]` if *`I`*` + n` is non-negative and less than
|
| 4303 |
+
`size()`, otherwise `T()`.
|
| 4304 |
+
|
| 4305 |
+
[*Note 1*: If element zero is taken as the leftmost element, a positive
|
| 4306 |
+
value of `n` shifts the elements left `n` places, with zero
|
| 4307 |
+
fill. — *end note*]
|
| 4308 |
+
|
| 4309 |
+
[*Example 1*: If the argument has the value -2, the first two elements
|
| 4310 |
+
of the result will be value-initialized ([[dcl.init]]); the third
|
| 4311 |
+
element of the result will be assigned the value of the first element of
|
| 4312 |
+
the argument; etc. — *end example*]
|
| 4313 |
+
|
| 4314 |
``` cpp
|
| 4315 |
+
valarray cshift(int n) const;
|
| 4316 |
```
|
| 4317 |
|
| 4318 |
+
*Returns:* A `valarray` of length `size()` that is a circular shift of
|
| 4319 |
+
`*this`. If element zero is taken as the leftmost element, a
|
| 4320 |
+
non-negative value of n shifts the elements circularly left n places and
|
| 4321 |
+
a negative value of n shifts the elements circularly right -n places.
|
| 4322 |
+
|
| 4323 |
``` cpp
|
| 4324 |
+
valarray apply(T func(T)) const;
|
| 4325 |
+
valarray apply(T func(const T&)) const;
|
| 4326 |
```
|
| 4327 |
|
| 4328 |
+
*Returns:* A `valarray` whose length is `size()`. Each element of the
|
| 4329 |
+
returned array is assigned the value returned by applying the argument
|
| 4330 |
+
function to the corresponding element of `*this`.
|
| 4331 |
+
|
| 4332 |
``` cpp
|
| 4333 |
void resize(size_t sz, T c = T());
|
| 4334 |
```
|
| 4335 |
|
| 4336 |
+
*Effects:* Changes the length of the `*this` array to `sz` and then
|
| 4337 |
+
assigns to each element the value of the second argument. Resizing
|
| 4338 |
+
invalidates all pointers and references to elements in the array.
|
| 4339 |
+
|
| 4340 |
### `valarray` non-member operations <a id="valarray.nonmembers">[[valarray.nonmembers]]</a>
|
| 4341 |
|
| 4342 |
#### `valarray` binary operators <a id="valarray.binary">[[valarray.binary]]</a>
|
| 4343 |
|
| 4344 |
``` cpp
|
|
|
|
| 4362 |
(const valarray<T>&, const valarray<T>&);
|
| 4363 |
template<class T> valarray<T> operator>>
|
| 4364 |
(const valarray<T>&, const valarray<T>&);
|
| 4365 |
```
|
| 4366 |
|
| 4367 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4368 |
+
`T` to which the indicated operator can be applied and for which the
|
| 4369 |
+
indicated operator returns a value which is of type `T` or which can be
|
| 4370 |
+
unambiguously implicitly converted to type `T`. The argument arrays have
|
| 4371 |
+
the same length.
|
| 4372 |
|
| 4373 |
+
*Returns:* A `valarray` whose length is equal to the lengths of the
|
| 4374 |
+
argument arrays. Each element of the returned array is initialized with
|
| 4375 |
+
the result of applying the indicated operator to the corresponding
|
| 4376 |
+
elements of the argument arrays.
|
|
|
|
|
|
|
|
|
|
| 4377 |
|
| 4378 |
``` cpp
|
| 4379 |
template<class T> valarray<T> operator* (const valarray<T>&, const T&);
|
| 4380 |
template<class T> valarray<T> operator* (const T&, const valarray<T>&);
|
| 4381 |
template<class T> valarray<T> operator/ (const valarray<T>&, const T&);
|
|
|
|
| 4396 |
template<class T> valarray<T> operator<<(const T&, const valarray<T>&);
|
| 4397 |
template<class T> valarray<T> operator>>(const valarray<T>&, const T&);
|
| 4398 |
template<class T> valarray<T> operator>>(const T&, const valarray<T>&);
|
| 4399 |
```
|
| 4400 |
|
| 4401 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4402 |
+
`T` to which the indicated operator can be applied and for which the
|
| 4403 |
+
indicated operator returns a value which is of type `T` or which can be
|
| 4404 |
unambiguously implicitly converted to type `T`.
|
| 4405 |
|
| 4406 |
+
*Returns:* A `valarray` whose length is equal to the length of the array
|
| 4407 |
+
argument. Each element of the returned array is initialized with the
|
| 4408 |
+
result of applying the indicated operator to the corresponding element
|
| 4409 |
+
of the array argument and the non-array argument.
|
| 4410 |
|
| 4411 |
#### `valarray` logical operators <a id="valarray.comparison">[[valarray.comparison]]</a>
|
| 4412 |
|
| 4413 |
``` cpp
|
| 4414 |
template<class T> valarray<bool> operator==
|
|
|
|
| 4427 |
(const valarray<T>&, const valarray<T>&);
|
| 4428 |
template<class T> valarray<bool> operator||
|
| 4429 |
(const valarray<T>&, const valarray<T>&);
|
| 4430 |
```
|
| 4431 |
|
| 4432 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4433 |
+
`T` to which the indicated operator can be applied and for which the
|
| 4434 |
+
indicated operator returns a value which is of type `bool` or which can
|
| 4435 |
+
be unambiguously implicitly converted to type `bool`. The two array
|
| 4436 |
+
arguments have the same length.
|
| 4437 |
|
| 4438 |
+
*Returns:* A `valarray<bool>` whose length is equal to the length of the
|
| 4439 |
+
array arguments. Each element of the returned array is initialized with
|
| 4440 |
+
the result of applying the indicated operator to the corresponding
|
| 4441 |
+
elements of the argument arrays.
|
|
|
|
|
|
|
|
|
|
| 4442 |
|
| 4443 |
``` cpp
|
| 4444 |
template<class T> valarray<bool> operator==(const valarray<T>&, const T&);
|
| 4445 |
template<class T> valarray<bool> operator==(const T&, const valarray<T>&);
|
| 4446 |
template<class T> valarray<bool> operator!=(const valarray<T>&, const T&);
|
|
|
|
| 4457 |
template<class T> valarray<bool> operator&&(const T&, const valarray<T>&);
|
| 4458 |
template<class T> valarray<bool> operator||(const valarray<T>&, const T&);
|
| 4459 |
template<class T> valarray<bool> operator||(const T&, const valarray<T>&);
|
| 4460 |
```
|
| 4461 |
|
| 4462 |
+
*Requires:* Each of these operators may only be instantiated for a type
|
| 4463 |
+
`T` to which the indicated operator can be applied and for which the
|
| 4464 |
+
indicated operator returns a value which is of type `bool` or which can
|
| 4465 |
+
be unambiguously implicitly converted to type `bool`.
|
| 4466 |
|
| 4467 |
+
*Returns:* A `valarray<bool>` whose length is equal to the length of the
|
| 4468 |
+
array argument. Each element of the returned array is initialized with
|
| 4469 |
+
the result of applying the indicated operator to the corresponding
|
| 4470 |
+
element of the array and the non-array argument.
|
| 4471 |
|
| 4472 |
#### `valarray` transcendentals <a id="valarray.transcend">[[valarray.transcend]]</a>
|
| 4473 |
|
| 4474 |
``` cpp
|
| 4475 |
template<class T> valarray<T> abs (const valarray<T>&);
|
|
|
|
| 4494 |
template<class T> valarray<T> sqrt (const valarray<T>&);
|
| 4495 |
template<class T> valarray<T> tan (const valarray<T>&);
|
| 4496 |
template<class T> valarray<T> tanh (const valarray<T>&);
|
| 4497 |
```
|
| 4498 |
|
| 4499 |
+
*Requires:* Each of these functions may only be instantiated for a type
|
| 4500 |
+
`T` to which a unique function with the indicated name can be applied
|
| 4501 |
+
(unqualified). This function shall return a value which is of type `T`
|
| 4502 |
+
or which can be unambiguously implicitly converted to type `T`.
|
| 4503 |
|
| 4504 |
#### `valarray` specialized algorithms <a id="valarray.special">[[valarray.special]]</a>
|
| 4505 |
|
| 4506 |
``` cpp
|
| 4507 |
template <class T> void swap(valarray<T>& x, valarray<T>& y) noexcept;
|
| 4508 |
```
|
| 4509 |
|
| 4510 |
+
*Effects:* Equivalent to `x.swap(y)`.
|
| 4511 |
|
| 4512 |
### Class `slice` <a id="class.slice">[[class.slice]]</a>
|
| 4513 |
|
| 4514 |
#### Class `slice` overview <a id="class.slice.overview">[[class.slice.overview]]</a>
|
| 4515 |
|
|
|
|
| 4526 |
};
|
| 4527 |
}
|
| 4528 |
```
|
| 4529 |
|
| 4530 |
The `slice` class represents a BLAS-like slice from an array. Such a
|
| 4531 |
+
slice is specified by a starting index, a length, and a stride.[^12]
|
| 4532 |
|
| 4533 |
#### `slice` constructors <a id="cons.slice">[[cons.slice]]</a>
|
| 4534 |
|
| 4535 |
``` cpp
|
| 4536 |
slice();
|
|
|
|
| 4541 |
The default constructor is equivalent to `slice(0, 0, 0)`. A default
|
| 4542 |
constructor is provided only to permit the declaration of arrays of
|
| 4543 |
slices. The constructor with arguments for a slice takes a start,
|
| 4544 |
length, and stride parameter.
|
| 4545 |
|
| 4546 |
+
[*Example 1*: `slice(3, 8, 2)` constructs a slice which selects
|
| 4547 |
+
elements 3, 5, 7, ... 17 from an array. — *end example*]
|
| 4548 |
|
| 4549 |
#### `slice` access functions <a id="slice.access">[[slice.access]]</a>
|
| 4550 |
|
| 4551 |
``` cpp
|
| 4552 |
size_t start() const;
|
|
|
|
| 4564 |
|
| 4565 |
``` cpp
|
| 4566 |
namespace std {
|
| 4567 |
template <class T> class slice_array {
|
| 4568 |
public:
|
| 4569 |
+
using value_type = T;
|
| 4570 |
|
| 4571 |
void operator= (const valarray<T>&) const;
|
| 4572 |
void operator*= (const valarray<T>&) const;
|
| 4573 |
void operator/= (const valarray<T>&) const;
|
| 4574 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4598 |
```
|
| 4599 |
|
| 4600 |
It has reference semantics to a subset of an array specified by a
|
| 4601 |
`slice` object.
|
| 4602 |
|
| 4603 |
+
[*Example 1*: The expression `a[slice(1, 5, 3)] = b;` has the effect of
|
| 4604 |
+
assigning the elements of `b` to a slice of the elements in `a`. For the
|
| 4605 |
+
slice shown, the elements selected from `a` are 1, 4, ...,
|
| 4606 |
+
13. — *end example*]
|
| 4607 |
|
| 4608 |
#### `slice_array` assignment <a id="slice.arr.assign">[[slice.arr.assign]]</a>
|
| 4609 |
|
| 4610 |
``` cpp
|
| 4611 |
void operator=(const valarray<T>&) const;
|
|
|
|
| 4614 |
|
| 4615 |
These assignment operators have reference semantics, assigning the
|
| 4616 |
values of the argument array elements to selected elements of the
|
| 4617 |
`valarray<T>` object to which the `slice_array` object refers.
|
| 4618 |
|
| 4619 |
+
#### `slice_array` compound assignment <a id="slice.arr.comp.assign">[[slice.arr.comp.assign]]</a>
|
| 4620 |
|
| 4621 |
``` cpp
|
| 4622 |
void operator*= (const valarray<T>&) const;
|
| 4623 |
void operator/= (const valarray<T>&) const;
|
| 4624 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4629 |
void operator|= (const valarray<T>&) const;
|
| 4630 |
void operator<<=(const valarray<T>&) const;
|
| 4631 |
void operator>>=(const valarray<T>&) const;
|
| 4632 |
```
|
| 4633 |
|
| 4634 |
+
These compound assignments have reference semantics, applying the
|
| 4635 |
indicated operation to the elements of the argument array and selected
|
| 4636 |
elements of the `valarray<T>` object to which the `slice_array` object
|
| 4637 |
refers.
|
| 4638 |
|
| 4639 |
#### `slice_array` fill function <a id="slice.arr.fill">[[slice.arr.fill]]</a>
|
|
|
|
| 4673 |
building multidimensional array classes using the `valarray` template,
|
| 4674 |
which is one-dimensional. The set of one-dimensional index values
|
| 4675 |
specified by a `gslice` are $$k = s + \sum_j i_j d_j$$ where the
|
| 4676 |
multidimensional indices iⱼ range in value from 0 to lᵢⱼ - 1.
|
| 4677 |
|
| 4678 |
+
[*Example 1*:
|
| 4679 |
+
|
| 4680 |
The `gslice` specification
|
| 4681 |
|
| 4682 |
``` cpp
|
| 4683 |
start = 3
|
| 4684 |
length = {2, 4, 3}
|
| 4685 |
stride = {19, 4, 1}
|
| 4686 |
```
|
| 4687 |
|
| 4688 |
yields the sequence of one-dimensional indices
|
|
|
|
| 4689 |
$$k = 3 + (0, 1) \times 19 + (0, 1, 2, 3) \times 4 + (0, 1, 2) \times 1$$
|
|
|
|
| 4690 |
which are ordered as shown in the following table:
|
| 4691 |
|
| 4692 |
That is, the highest-ordered index turns fastest.
|
| 4693 |
|
| 4694 |
+
— *end example*]
|
| 4695 |
+
|
| 4696 |
It is possible to have degenerate generalized slices in which an address
|
| 4697 |
is repeated.
|
| 4698 |
|
| 4699 |
+
[*Example 2*:
|
| 4700 |
+
|
| 4701 |
If the stride parameters in the previous example are changed to {1, 1,
|
| 4702 |
1}, the first few elements of the resulting sequence of indices will be
|
| 4703 |
|
| 4704 |
+
— *end example*]
|
| 4705 |
+
|
| 4706 |
If a degenerate slice is used as the argument to the non-`const` version
|
| 4707 |
+
of `operator[](const gslice&)`, the behavior is undefined.
|
| 4708 |
|
| 4709 |
#### `gslice` constructors <a id="gslice.cons">[[gslice.cons]]</a>
|
| 4710 |
|
| 4711 |
``` cpp
|
| 4712 |
gslice();
|
|
|
|
| 4740 |
|
| 4741 |
``` cpp
|
| 4742 |
namespace std {
|
| 4743 |
template <class T> class gslice_array {
|
| 4744 |
public:
|
| 4745 |
+
using value_type = T;
|
| 4746 |
|
| 4747 |
void operator= (const valarray<T>&) const;
|
| 4748 |
void operator*= (const valarray<T>&) const;
|
| 4749 |
void operator/= (const valarray<T>&) const;
|
| 4750 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4789 |
|
| 4790 |
These assignment operators have reference semantics, assigning the
|
| 4791 |
values of the argument array elements to selected elements of the
|
| 4792 |
`valarray<T>` object to which the `gslice_array` refers.
|
| 4793 |
|
| 4794 |
+
#### `gslice_array` compound assignment <a id="gslice.array.comp.assign">[[gslice.array.comp.assign]]</a>
|
| 4795 |
|
| 4796 |
``` cpp
|
| 4797 |
void operator*= (const valarray<T>&) const;
|
| 4798 |
void operator/= (const valarray<T>&) const;
|
| 4799 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4804 |
void operator|= (const valarray<T>&) const;
|
| 4805 |
void operator<<=(const valarray<T>&) const;
|
| 4806 |
void operator>>=(const valarray<T>&) const;
|
| 4807 |
```
|
| 4808 |
|
| 4809 |
+
These compound assignments have reference semantics, applying the
|
| 4810 |
indicated operation to the elements of the argument array and selected
|
| 4811 |
elements of the `valarray<T>` object to which the `gslice_array` object
|
| 4812 |
refers.
|
| 4813 |
|
| 4814 |
#### `gslice_array` fill function <a id="gslice.array.fill">[[gslice.array.fill]]</a>
|
|
|
|
| 4827 |
|
| 4828 |
``` cpp
|
| 4829 |
namespace std {
|
| 4830 |
template <class T> class mask_array {
|
| 4831 |
public:
|
| 4832 |
+
using value_type = T;
|
| 4833 |
|
| 4834 |
void operator= (const valarray<T>&) const;
|
| 4835 |
void operator*= (const valarray<T>&) const;
|
| 4836 |
void operator/= (const valarray<T>&) const;
|
| 4837 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4873 |
|
| 4874 |
These assignment operators have reference semantics, assigning the
|
| 4875 |
values of the argument array elements to selected elements of the
|
| 4876 |
`valarray<T>` object to which it refers.
|
| 4877 |
|
| 4878 |
+
#### `mask_array` compound assignment <a id="mask.array.comp.assign">[[mask.array.comp.assign]]</a>
|
| 4879 |
|
| 4880 |
``` cpp
|
| 4881 |
void operator*= (const valarray<T>&) const;
|
| 4882 |
void operator/= (const valarray<T>&) const;
|
| 4883 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4888 |
void operator|= (const valarray<T>&) const;
|
| 4889 |
void operator<<=(const valarray<T>&) const;
|
| 4890 |
void operator>>=(const valarray<T>&) const;
|
| 4891 |
```
|
| 4892 |
|
| 4893 |
+
These compound assignments have reference semantics, applying the
|
| 4894 |
indicated operation to the elements of the argument array and selected
|
| 4895 |
elements of the `valarray<T>` object to which the mask object refers.
|
| 4896 |
|
| 4897 |
#### `mask_array` fill function <a id="mask.array.fill">[[mask.array.fill]]</a>
|
| 4898 |
|
|
|
|
| 4910 |
|
| 4911 |
``` cpp
|
| 4912 |
namespace std {
|
| 4913 |
template <class T> class indirect_array {
|
| 4914 |
public:
|
| 4915 |
+
using value_type = T;
|
| 4916 |
|
| 4917 |
void operator= (const valarray<T>&) const;
|
| 4918 |
void operator*= (const valarray<T>&) const;
|
| 4919 |
void operator/= (const valarray<T>&) const;
|
| 4920 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4960 |
`valarray<T>` object to which it refers.
|
| 4961 |
|
| 4962 |
If the `indirect_array` specifies an element in the `valarray<T>` object
|
| 4963 |
to which it refers more than once, the behavior is undefined.
|
| 4964 |
|
| 4965 |
+
[*Example 1*:
|
| 4966 |
+
|
| 4967 |
``` cpp
|
| 4968 |
int addr[] = {2, 3, 1, 4, 4};
|
| 4969 |
valarray<size_t> indirect(addr, 5);
|
| 4970 |
valarray<double> a(0., 10), b(1., 5);
|
| 4971 |
a[indirect] = b;
|
| 4972 |
```
|
| 4973 |
|
| 4974 |
results in undefined behavior since element 4 is specified twice in the
|
| 4975 |
indirection.
|
| 4976 |
|
| 4977 |
+
— *end example*]
|
| 4978 |
+
|
| 4979 |
+
#### `indirect_array` compound assignment <a id="indirect.array.comp.assign">[[indirect.array.comp.assign]]</a>
|
| 4980 |
|
| 4981 |
``` cpp
|
| 4982 |
void operator*= (const valarray<T>&) const;
|
| 4983 |
void operator/= (const valarray<T>&) const;
|
| 4984 |
void operator%= (const valarray<T>&) const;
|
|
|
|
| 4989 |
void operator|= (const valarray<T>&) const;
|
| 4990 |
void operator<<=(const valarray<T>&) const;
|
| 4991 |
void operator>>=(const valarray<T>&) const;
|
| 4992 |
```
|
| 4993 |
|
| 4994 |
+
These compound assignments have reference semantics, applying the
|
| 4995 |
indicated operation to the elements of the argument array and selected
|
| 4996 |
elements of the `valarray<T>` object to which the `indirect_array`
|
| 4997 |
object refers.
|
| 4998 |
|
| 4999 |
If the `indirect_array` specifies an element in the `valarray<T>` object
|
|
|
|
| 5007 |
|
| 5008 |
This function has reference semantics, assigning the value of its
|
| 5009 |
argument to the elements of the `valarray<T>` object to which the
|
| 5010 |
`indirect_array` object refers.
|
| 5011 |
|
| 5012 |
+
### `valarray` range access <a id="valarray.range">[[valarray.range]]</a>
|
| 5013 |
|
| 5014 |
In the `begin` and `end` function templates that follow, *unspecified*1
|
| 5015 |
is a type that meets the requirements of a mutable random access
|
| 5016 |
+
iterator ([[random.access.iterators]]) and of a contiguous iterator (
|
| 5017 |
+
[[iterator.requirements.general]]) whose `value_type` is the template
|
| 5018 |
+
parameter `T` and whose `reference` type is `T&`. *unspecified*2 is a
|
| 5019 |
+
type that meets the requirements of a constant random access iterator (
|
| 5020 |
+
[[random.access.iterators]]) and of a contiguous iterator (
|
| 5021 |
+
[[iterator.requirements.general]]) whose `value_type` is the template
|
| 5022 |
+
parameter `T` and whose `reference` type is `const T&`.
|
| 5023 |
|
| 5024 |
The iterators returned by `begin` and `end` for an array are guaranteed
|
| 5025 |
to be valid until the member function `resize(size_t, T)` (
|
| 5026 |
[[valarray.members]]) is called for that array or until the lifetime of
|
| 5027 |
that array ends, whichever happens first.
|
|
|
|
| 5029 |
``` cpp
|
| 5030 |
template <class T> unspecified{1} begin(valarray<T>& v);
|
| 5031 |
template <class T> unspecified{2} begin(const valarray<T>& v);
|
| 5032 |
```
|
| 5033 |
|
| 5034 |
+
*Returns:* An iterator referencing the first value in the array.
|
| 5035 |
|
| 5036 |
``` cpp
|
| 5037 |
template <class T> unspecified{1} end(valarray<T>& v);
|
| 5038 |
template <class T> unspecified{2} end(const valarray<T>& v);
|
| 5039 |
```
|
| 5040 |
|
| 5041 |
+
*Returns:* An iterator referencing one past the last value in the array.
|
|
|
|
| 5042 |
|
| 5043 |
## Generalized numeric operations <a id="numeric.ops">[[numeric.ops]]</a>
|
| 5044 |
|
| 5045 |
### Header `<numeric>` synopsis <a id="numeric.ops.overview">[[numeric.ops.overview]]</a>
|
| 5046 |
|
| 5047 |
``` cpp
|
| 5048 |
namespace std {
|
| 5049 |
+
// [accumulate], accumulate
|
| 5050 |
template <class InputIterator, class T>
|
| 5051 |
T accumulate(InputIterator first, InputIterator last, T init);
|
| 5052 |
template <class InputIterator, class T, class BinaryOperation>
|
| 5053 |
T accumulate(InputIterator first, InputIterator last, T init,
|
| 5054 |
BinaryOperation binary_op);
|
| 5055 |
|
| 5056 |
+
// [reduce], reduce
|
| 5057 |
+
template<class InputIterator>
|
| 5058 |
+
typename iterator_traits<InputIterator>::value_type
|
| 5059 |
+
reduce(InputIterator first, InputIterator last);
|
| 5060 |
+
template<class InputIterator, class T>
|
| 5061 |
+
T reduce(InputIterator first, InputIterator last, T init);
|
| 5062 |
+
template<class InputIterator, class T, class BinaryOperation>
|
| 5063 |
+
T reduce(InputIterator first, InputIterator last, T init,
|
| 5064 |
+
BinaryOperation binary_op);
|
| 5065 |
+
template<class ExecutionPolicy, class ForwardIterator>
|
| 5066 |
+
typename iterator_traits<ForwardIterator>::value_type
|
| 5067 |
+
reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5068 |
+
ForwardIterator first, ForwardIterator last);
|
| 5069 |
+
template<class ExecutionPolicy, class ForwardIterator, class T>
|
| 5070 |
+
T reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5071 |
+
ForwardIterator first, ForwardIterator last, T init);
|
| 5072 |
+
template<class ExecutionPolicy, class ForwardIterator, class T, class BinaryOperation>
|
| 5073 |
+
T reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5074 |
+
ForwardIterator first, ForwardIterator last, T init,
|
| 5075 |
+
BinaryOperation binary_op);
|
| 5076 |
+
|
| 5077 |
+
// [inner.product], inner product
|
| 5078 |
template <class InputIterator1, class InputIterator2, class T>
|
| 5079 |
T inner_product(InputIterator1 first1, InputIterator1 last1,
|
| 5080 |
InputIterator2 first2, T init);
|
| 5081 |
template <class InputIterator1, class InputIterator2, class T,
|
| 5082 |
class BinaryOperation1, class BinaryOperation2>
|
| 5083 |
T inner_product(InputIterator1 first1, InputIterator1 last1,
|
| 5084 |
InputIterator2 first2, T init,
|
| 5085 |
BinaryOperation1 binary_op1,
|
| 5086 |
BinaryOperation2 binary_op2);
|
| 5087 |
|
| 5088 |
+
// [transform.reduce], transform reduce
|
| 5089 |
+
template<class InputIterator1, class InputIterator2, class T>
|
| 5090 |
+
T transform_reduce(InputIterator1 first1, InputIterator1 last1,
|
| 5091 |
+
InputIterator2 first2,
|
| 5092 |
+
T init);
|
| 5093 |
+
template<class InputIterator1, class InputIterator2, class T,
|
| 5094 |
+
class BinaryOperation1, class BinaryOperation2>
|
| 5095 |
+
T transform_reduce(InputIterator1 first1, InputIterator1 last1,
|
| 5096 |
+
InputIterator2 first2,
|
| 5097 |
+
T init,
|
| 5098 |
+
BinaryOperation1 binary_op1,
|
| 5099 |
+
BinaryOperation2 binary_op2);
|
| 5100 |
+
template<class InputIterator, class T,
|
| 5101 |
+
class BinaryOperation, class UnaryOperation>
|
| 5102 |
+
T transform_reduce(InputIterator first, InputIterator last,
|
| 5103 |
+
T init,
|
| 5104 |
+
BinaryOperation binary_op, UnaryOperation unary_op);
|
| 5105 |
+
template<class ExecutionPolicy,
|
| 5106 |
+
class ForwardIterator1, class ForwardIterator2, class T>
|
| 5107 |
+
T transform_reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5108 |
+
ForwardIterator1 first1, ForwardIterator1 last1,
|
| 5109 |
+
ForwardIterator2 first2,
|
| 5110 |
+
T init);
|
| 5111 |
+
template<class ExecutionPolicy,
|
| 5112 |
+
class ForwardIterator1, class ForwardIterator2, class T,
|
| 5113 |
+
class BinaryOperation1, class BinaryOperation2>
|
| 5114 |
+
T transform_reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5115 |
+
ForwardIterator1 first1, ForwardIterator1 last1,
|
| 5116 |
+
ForwardIterator2 first2,
|
| 5117 |
+
T init,
|
| 5118 |
+
BinaryOperation1 binary_op1,
|
| 5119 |
+
BinaryOperation2 binary_op2);
|
| 5120 |
+
template<class ExecutionPolicy,
|
| 5121 |
+
class ForwardIterator, class T,
|
| 5122 |
+
class BinaryOperation, class UnaryOperation>
|
| 5123 |
+
T transform_reduce(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5124 |
+
ForwardIterator first, ForwardIterator last,
|
| 5125 |
+
T init,
|
| 5126 |
+
BinaryOperation binary_op, UnaryOperation unary_op);
|
| 5127 |
+
|
| 5128 |
+
// [partial.sum], partial sum
|
| 5129 |
template <class InputIterator, class OutputIterator>
|
| 5130 |
OutputIterator partial_sum(InputIterator first,
|
| 5131 |
InputIterator last,
|
| 5132 |
OutputIterator result);
|
| 5133 |
+
template <class InputIterator, class OutputIterator, class BinaryOperation>
|
|
|
|
| 5134 |
OutputIterator partial_sum(InputIterator first,
|
| 5135 |
InputIterator last,
|
| 5136 |
OutputIterator result,
|
| 5137 |
BinaryOperation binary_op);
|
| 5138 |
|
| 5139 |
+
// [exclusive.scan], exclusive scan
|
| 5140 |
+
template<class InputIterator, class OutputIterator, class T>
|
| 5141 |
+
OutputIterator exclusive_scan(InputIterator first, InputIterator last,
|
| 5142 |
+
OutputIterator result,
|
| 5143 |
+
T init);
|
| 5144 |
+
template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
|
| 5145 |
+
OutputIterator exclusive_scan(InputIterator first, InputIterator last,
|
| 5146 |
+
OutputIterator result,
|
| 5147 |
+
T init, BinaryOperation binary_op);
|
| 5148 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2, class T>
|
| 5149 |
+
ForwardIterator2 exclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5150 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5151 |
+
ForwardIterator2 result,
|
| 5152 |
+
T init);
|
| 5153 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2, class T,
|
| 5154 |
+
class BinaryOperation>
|
| 5155 |
+
ForwardIterator2 exclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5156 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5157 |
+
ForwardIterator2 result,
|
| 5158 |
+
T init, BinaryOperation binary_op);
|
| 5159 |
+
|
| 5160 |
+
// [inclusive.scan], inclusive scan
|
| 5161 |
+
template<class InputIterator, class OutputIterator>
|
| 5162 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5163 |
+
OutputIterator result);
|
| 5164 |
+
template<class InputIterator, class OutputIterator, class BinaryOperation>
|
| 5165 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5166 |
+
OutputIterator result,
|
| 5167 |
+
BinaryOperation binary_op);
|
| 5168 |
+
template<class InputIterator, class OutputIterator, class BinaryOperation, class T>
|
| 5169 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5170 |
+
OutputIterator result,
|
| 5171 |
+
BinaryOperation binary_op, T init);
|
| 5172 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
|
| 5173 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5174 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5175 |
+
ForwardIterator2 result);
|
| 5176 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
|
| 5177 |
+
class BinaryOperation>
|
| 5178 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5179 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5180 |
+
ForwardIterator2 result,
|
| 5181 |
+
BinaryOperation binary_op);
|
| 5182 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
|
| 5183 |
+
class BinaryOperation, class T>
|
| 5184 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5185 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5186 |
+
ForwardIterator2 result,
|
| 5187 |
+
BinaryOperation binary_op, T init);
|
| 5188 |
+
|
| 5189 |
+
// [transform.exclusive.scan], transform exclusive scan
|
| 5190 |
+
template<class InputIterator, class OutputIterator, class T,
|
| 5191 |
+
class BinaryOperation, class UnaryOperation>
|
| 5192 |
+
OutputIterator transform_exclusive_scan(InputIterator first, InputIterator last,
|
| 5193 |
+
OutputIterator result,
|
| 5194 |
+
T init,
|
| 5195 |
+
BinaryOperation binary_op,
|
| 5196 |
+
UnaryOperation unary_op);
|
| 5197 |
+
template<class ExecutionPolicy,
|
| 5198 |
+
class ForwardIterator1, class ForwardIterator2, class T,
|
| 5199 |
+
class BinaryOperation, class UnaryOperation>
|
| 5200 |
+
ForwardIterator2 transform_exclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5201 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5202 |
+
ForwardIterator2 result,
|
| 5203 |
+
T init,
|
| 5204 |
+
BinaryOperation binary_op,
|
| 5205 |
+
UnaryOperation unary_op);
|
| 5206 |
+
|
| 5207 |
+
// [transform.inclusive.scan], transform inclusive scan
|
| 5208 |
+
template<class InputIterator, class OutputIterator,
|
| 5209 |
+
class BinaryOperation, class UnaryOperation>
|
| 5210 |
+
OutputIterator transform_inclusive_scan(InputIterator first, InputIterator last,
|
| 5211 |
+
OutputIterator result,
|
| 5212 |
+
BinaryOperation binary_op,
|
| 5213 |
+
UnaryOperation unary_op);
|
| 5214 |
+
template<class InputIterator, class OutputIterator,
|
| 5215 |
+
class BinaryOperation, class UnaryOperation, class T>
|
| 5216 |
+
OutputIterator transform_inclusive_scan(InputIterator first, InputIterator last,
|
| 5217 |
+
OutputIterator result,
|
| 5218 |
+
BinaryOperation binary_op,
|
| 5219 |
+
UnaryOperation unary_op,
|
| 5220 |
+
T init);
|
| 5221 |
+
template<class ExecutionPolicy,
|
| 5222 |
+
class ForwardIterator1, class ForwardIterator2,
|
| 5223 |
+
class BinaryOperation, class UnaryOperation>
|
| 5224 |
+
ForwardIterator2 transform_inclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5225 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5226 |
+
ForwardIterator2 result,
|
| 5227 |
+
BinaryOperation binary_op,
|
| 5228 |
+
UnaryOperation unary_op);
|
| 5229 |
+
template<class ExecutionPolicy,
|
| 5230 |
+
class ForwardIterator1, class ForwardIterator2,
|
| 5231 |
+
class BinaryOperation, class UnaryOperation, class T>
|
| 5232 |
+
ForwardIterator2 transform_inclusive_scan(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5233 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5234 |
+
ForwardIterator2 result,
|
| 5235 |
+
BinaryOperation binary_op,
|
| 5236 |
+
UnaryOperation unary_op,
|
| 5237 |
+
T init);
|
| 5238 |
+
|
| 5239 |
+
// [adjacent.difference], adjacent difference
|
| 5240 |
template <class InputIterator, class OutputIterator>
|
| 5241 |
OutputIterator adjacent_difference(InputIterator first,
|
| 5242 |
InputIterator last,
|
| 5243 |
OutputIterator result);
|
| 5244 |
+
template <class InputIterator, class OutputIterator, class BinaryOperation>
|
|
|
|
| 5245 |
OutputIterator adjacent_difference(InputIterator first,
|
| 5246 |
InputIterator last,
|
| 5247 |
OutputIterator result,
|
| 5248 |
BinaryOperation binary_op);
|
| 5249 |
+
template <class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
|
| 5250 |
+
ForwardIterator2 adjacent_difference(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5251 |
+
ForwardIterator1 first,
|
| 5252 |
+
ForwardIterator1 last,
|
| 5253 |
+
ForwardIterator2 result);
|
| 5254 |
+
template <class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
|
| 5255 |
+
class BinaryOperation>
|
| 5256 |
+
ForwardIterator2 adjacent_difference(ExecutionPolicy&& exec, // see [algorithms.parallel.overloads]
|
| 5257 |
+
ForwardIterator1 first,
|
| 5258 |
+
ForwardIterator1 last,
|
| 5259 |
+
ForwardIterator2 result,
|
| 5260 |
+
BinaryOperation binary_op);
|
| 5261 |
|
| 5262 |
+
// [numeric.iota], iota
|
| 5263 |
template <class ForwardIterator, class T>
|
| 5264 |
void iota(ForwardIterator first, ForwardIterator last, T value);
|
| 5265 |
+
|
| 5266 |
+
// [numeric.ops.gcd], greatest common divisor
|
| 5267 |
+
template <class M, class N>
|
| 5268 |
+
constexpr common_type_t<M,N> gcd(M m, N n);
|
| 5269 |
+
|
| 5270 |
+
// [numeric.ops.lcm], least common multiple
|
| 5271 |
+
template <class M, class N>
|
| 5272 |
+
constexpr common_type_t<M,N> lcm(M m, N n);
|
| 5273 |
}
|
| 5274 |
```
|
| 5275 |
|
| 5276 |
The requirements on the types of algorithms’ arguments that are
|
| 5277 |
described in the introduction to Clause [[algorithms]] also apply to
|
| 5278 |
the following algorithms.
|
| 5279 |
|
| 5280 |
+
Throughout this subclause, the parameters `UnaryOperation`,
|
| 5281 |
+
`BinaryOperation`, `BinaryOperation1`, and `BinaryOperation2` are used
|
| 5282 |
+
whenever an algorithm expects a function object ([[function.objects]]).
|
| 5283 |
+
|
| 5284 |
+
[*Note 1*: The use of closed ranges as well as semi-open ranges to
|
| 5285 |
+
specify requirements throughout this subclause is
|
| 5286 |
+
intentional. — *end note*]
|
| 5287 |
+
|
| 5288 |
### Accumulate <a id="accumulate">[[accumulate]]</a>
|
| 5289 |
|
| 5290 |
``` cpp
|
| 5291 |
template <class InputIterator, class T>
|
| 5292 |
T accumulate(InputIterator first, InputIterator last, T init);
|
| 5293 |
template <class InputIterator, class T, class BinaryOperation>
|
| 5294 |
T accumulate(InputIterator first, InputIterator last, T init,
|
| 5295 |
BinaryOperation binary_op);
|
| 5296 |
```
|
| 5297 |
|
| 5298 |
+
*Requires:* `T` shall meet the requirements of `CopyConstructible`
|
| 5299 |
+
(Table [[tab:copyconstructible]]) and `CopyAssignable`
|
| 5300 |
+
(Table [[tab:copyassignable]]) types. In the range \[`first`, `last`\],
|
| 5301 |
+
`binary_op` shall neither modify elements nor invalidate iterators or
|
| 5302 |
+
subranges.[^13]
|
| 5303 |
+
|
| 5304 |
*Effects:* Computes its result by initializing the accumulator `acc`
|
| 5305 |
with the initial value `init` and then modifies it with `acc = acc + *i`
|
| 5306 |
or `acc = binary_op(acc, *i)` for every iterator `i` in the range
|
| 5307 |
+
\[`first`, `last`) in order.[^14]
|
| 5308 |
|
| 5309 |
+
### Reduce <a id="reduce">[[reduce]]</a>
|
| 5310 |
+
|
| 5311 |
+
``` cpp
|
| 5312 |
+
template<class InputIterator>
|
| 5313 |
+
typename iterator_traits<InputIterator>::value_type
|
| 5314 |
+
reduce(InputIterator first, InputIterator last);
|
| 5315 |
+
```
|
| 5316 |
+
|
| 5317 |
+
*Effects:* Equivalent to:
|
| 5318 |
+
|
| 5319 |
+
``` cpp
|
| 5320 |
+
return reduce(first, last,
|
| 5321 |
+
typename iterator_traits<InputIterator>::value_type{});
|
| 5322 |
+
```
|
| 5323 |
+
|
| 5324 |
+
``` cpp
|
| 5325 |
+
template<class ExecutionPolicy, class ForwardIterator>
|
| 5326 |
+
typename iterator_traits<ForwardIterator>::value_type
|
| 5327 |
+
reduce(ExecutionPolicy&& exec,
|
| 5328 |
+
ForwardIterator first, ForwardIterator last);
|
| 5329 |
+
```
|
| 5330 |
+
|
| 5331 |
+
*Effects:* Equivalent to:
|
| 5332 |
+
|
| 5333 |
+
``` cpp
|
| 5334 |
+
return reduce(std::forward<ExecutionPolicy>(exec), first, last,
|
| 5335 |
+
typename iterator_traits<ForwardIterator>::value_type{});
|
| 5336 |
+
```
|
| 5337 |
+
|
| 5338 |
+
``` cpp
|
| 5339 |
+
template<class InputIterator, class T>
|
| 5340 |
+
T reduce(InputIterator first, InputIterator last, T init);
|
| 5341 |
+
```
|
| 5342 |
+
|
| 5343 |
+
*Effects:* Equivalent to:
|
| 5344 |
+
|
| 5345 |
+
``` cpp
|
| 5346 |
+
return reduce(first, last, init, plus<>());
|
| 5347 |
+
```
|
| 5348 |
+
|
| 5349 |
+
``` cpp
|
| 5350 |
+
template<class ExecutionPolicy, class ForwardIterator, class T>
|
| 5351 |
+
T reduce(ExecutionPolicy&& exec,
|
| 5352 |
+
ForwardIterator first, ForwardIterator last, T init);
|
| 5353 |
+
```
|
| 5354 |
+
|
| 5355 |
+
*Effects:* Equivalent to:
|
| 5356 |
+
|
| 5357 |
+
``` cpp
|
| 5358 |
+
return reduce(std::forward<ExecutionPolicy>(exec), first, last, init, plus<>());
|
| 5359 |
+
```
|
| 5360 |
+
|
| 5361 |
+
``` cpp
|
| 5362 |
+
template<class InputIterator, class T, class BinaryOperation>
|
| 5363 |
+
T reduce(InputIterator first, InputIterator last, T init,
|
| 5364 |
+
BinaryOperation binary_op);
|
| 5365 |
+
template<class ExecutionPolicy, class ForwardIterator, class T, class BinaryOperation>
|
| 5366 |
+
T reduce(ExecutionPolicy&& exec,
|
| 5367 |
+
ForwardIterator first, ForwardIterator last, T init,
|
| 5368 |
+
BinaryOperation binary_op);
|
| 5369 |
+
```
|
| 5370 |
+
|
| 5371 |
+
*Requires:*
|
| 5372 |
+
|
| 5373 |
+
- `T` shall be `MoveConstructible` (Table [[tab:moveconstructible]]).
|
| 5374 |
+
- All of `binary_op(init, *first)`, `binary_op(*first, init)`,
|
| 5375 |
+
`binary_op(init, init)`, and `binary_op(*first, *first)` shall be
|
| 5376 |
+
convertible to `T`.
|
| 5377 |
+
- `binary_op` shall neither invalidate iterators or subranges, nor
|
| 5378 |
+
modify elements in the range \[`first`, `last`\].
|
| 5379 |
+
|
| 5380 |
+
*Returns:* *GENERALIZED_SUM*(binary_op, init, \*i, ...) for every `i` in
|
| 5381 |
+
\[`first`, `last`).
|
| 5382 |
+
|
| 5383 |
+
*Complexity:* 𝑂(`last - first`) applications of `binary_op`.
|
| 5384 |
+
|
| 5385 |
+
[*Note 1*: The difference between `reduce` and `accumulate` is that
|
| 5386 |
+
`reduce` applies `binary_op` in an unspecified order, which yields a
|
| 5387 |
+
nondeterministic result for non-associative or non-commutative
|
| 5388 |
+
`binary_op` such as floating-point addition. — *end note*]
|
| 5389 |
|
| 5390 |
### Inner product <a id="inner.product">[[inner.product]]</a>
|
| 5391 |
|
| 5392 |
``` cpp
|
| 5393 |
template <class InputIterator1, class InputIterator2, class T>
|
|
|
|
| 5399 |
InputIterator2 first2, T init,
|
| 5400 |
BinaryOperation1 binary_op1,
|
| 5401 |
BinaryOperation2 binary_op2);
|
| 5402 |
```
|
| 5403 |
|
| 5404 |
+
*Requires:* `T` shall meet the requirements of `CopyConstructible`
|
| 5405 |
+
(Table [[tab:copyconstructible]]) and `CopyAssignable`
|
| 5406 |
+
(Table [[tab:copyassignable]]) types. In the ranges \[`first1`,
|
| 5407 |
+
`last1`\] and \[`first2`, `first2 + (last1 - first1)`\] `binary_op1` and
|
| 5408 |
+
`binary_op2` shall neither modify elements nor invalidate iterators or
|
| 5409 |
+
subranges.[^15]
|
| 5410 |
+
|
| 5411 |
*Effects:* Computes its result by initializing the accumulator `acc`
|
| 5412 |
with the initial value `init` and then modifying it with
|
| 5413 |
`acc = acc + (*i1) * (*i2)` or
|
| 5414 |
`acc = binary_op1(acc, binary_op2(*i1, *i2))` for every iterator `i1` in
|
| 5415 |
the range \[`first1`, `last1`) and iterator `i2` in the range
|
| 5416 |
\[`first2`, `first2 + (last1 - first1)`) in order.
|
| 5417 |
|
| 5418 |
+
### Transform reduce <a id="transform.reduce">[[transform.reduce]]</a>
|
| 5419 |
+
|
| 5420 |
+
``` cpp
|
| 5421 |
+
template <class InputIterator1, class InputIterator2, class T>
|
| 5422 |
+
T transform_reduce(InputIterator1 first1, InputIterator1 last1,
|
| 5423 |
+
InputIterator2 first2,
|
| 5424 |
+
T init);
|
| 5425 |
+
template <class ExecutionPolicy,
|
| 5426 |
+
class ForwardIterator1, class ForwardIterator2, class T>
|
| 5427 |
+
T transform_reduce(ExecutionPolicy&& exec,
|
| 5428 |
+
ForwardIterator1 first1, ForwardIterator1 last1,
|
| 5429 |
+
ForwardIterator2 first2,
|
| 5430 |
+
T init);
|
| 5431 |
+
```
|
| 5432 |
+
|
| 5433 |
+
*Effects:* Equivalent to:
|
| 5434 |
+
|
| 5435 |
+
``` cpp
|
| 5436 |
+
return transform_reduce(first1, last1, first2, init, plus<>(), multiplies<>());
|
| 5437 |
+
```
|
| 5438 |
+
|
| 5439 |
+
``` cpp
|
| 5440 |
+
template <class InputIterator1, class InputIterator2, class T,
|
| 5441 |
+
class BinaryOperation1, class BinaryOperation2>
|
| 5442 |
+
T transform_reduce(InputIterator1 first1, InputIterator1 last1,
|
| 5443 |
+
InputIterator2 first2,
|
| 5444 |
+
T init,
|
| 5445 |
+
BinaryOperation1 binary_op1,
|
| 5446 |
+
BinaryOperation2 binary_op2);
|
| 5447 |
+
template <class ExecutionPolicy,
|
| 5448 |
+
class ForwardIterator1, class ForwardIterator2, class T,
|
| 5449 |
+
class BinaryOperation1, class BinaryOperation2>
|
| 5450 |
+
T transform_reduce(ExecutionPolicy&& exec,
|
| 5451 |
+
ForwardIterator1 first1, ForwardIterator1 last1,
|
| 5452 |
+
ForwardIterator2 first2,
|
| 5453 |
+
T init,
|
| 5454 |
+
BinaryOperation1 binary_op1,
|
| 5455 |
+
BinaryOperation2 binary_op2);
|
| 5456 |
+
```
|
| 5457 |
+
|
| 5458 |
+
*Requires:*
|
| 5459 |
+
|
| 5460 |
+
- `T` shall be `MoveConstructible` (Table [[tab:moveconstructible]]).
|
| 5461 |
+
- All of
|
| 5462 |
+
- `binary_op1(init, init)`,
|
| 5463 |
+
- `binary_op1(init, binary_op2(*first1, *first2))`,
|
| 5464 |
+
- `binary_op1(binary_op2(*first1, *first2), init)`, and
|
| 5465 |
+
- `binary_op1(binary_op2(*first1, *first2), binary_op2(*first1, *first2))`
|
| 5466 |
+
|
| 5467 |
+
shall be convertible to `T`.
|
| 5468 |
+
- Neither `binary_op1` nor `binary_op2` shall invalidate subranges, or
|
| 5469 |
+
modify elements in the ranges \[`first1`, `last1`\] and \[`first2`,
|
| 5470 |
+
`first2 + (last1 - first1)`\].
|
| 5471 |
+
|
| 5472 |
+
*Returns:*
|
| 5473 |
+
|
| 5474 |
+
``` cpp
|
| 5475 |
+
GENERALIZED_SUM(binary_op1, init, binary_op2(*i, *(first2 + (i - first1))), ...)
|
| 5476 |
+
```
|
| 5477 |
+
|
| 5478 |
+
for every iterator `i` in \[`first1`, `last1`).
|
| 5479 |
+
|
| 5480 |
+
*Complexity:* 𝑂(`last1 - first1`) applications each of `binary_op1` and
|
| 5481 |
+
`binary_op2`.
|
| 5482 |
+
|
| 5483 |
+
``` cpp
|
| 5484 |
+
template<class InputIterator, class T,
|
| 5485 |
+
class BinaryOperation, class UnaryOperation>
|
| 5486 |
+
T transform_reduce(InputIterator first, InputIterator last, T init,
|
| 5487 |
+
BinaryOperation binary_op, UnaryOperation unary_op);
|
| 5488 |
+
template<class ExecutionPolicy,
|
| 5489 |
+
class ForwardIterator, class T,
|
| 5490 |
+
class BinaryOperation, class UnaryOperation>
|
| 5491 |
+
T transform_reduce(ExecutionPolicy&& exec,
|
| 5492 |
+
ForwardIterator first, ForwardIterator last,
|
| 5493 |
+
T init, BinaryOperation binary_op, UnaryOperation unary_op);
|
| 5494 |
+
```
|
| 5495 |
+
|
| 5496 |
+
*Requires:*
|
| 5497 |
+
|
| 5498 |
+
- `T` shall be `MoveConstructible` (Table [[tab:moveconstructible]]).
|
| 5499 |
+
- All of
|
| 5500 |
+
- `binary_op(init, init)`,
|
| 5501 |
+
- `binary_op(init, unary_op(*first))`,
|
| 5502 |
+
- `binary_op(unary_op(*first), init)`, and
|
| 5503 |
+
- `binary_op(unary_op(*first), unary_op(*first))`
|
| 5504 |
+
|
| 5505 |
+
shall be convertible to `T`.
|
| 5506 |
+
- Neither `unary_op` nor `binary_op` shall invalidate subranges, or
|
| 5507 |
+
modify elements in the range \[`first`, `last`\].
|
| 5508 |
+
|
| 5509 |
+
*Returns:*
|
| 5510 |
+
|
| 5511 |
+
``` cpp
|
| 5512 |
+
GENERALIZED_SUM(binary_op, init, unary_op(*i), ...)
|
| 5513 |
+
```
|
| 5514 |
+
|
| 5515 |
+
for every iterator `i` in \[`first`, `last`).
|
| 5516 |
+
|
| 5517 |
+
*Complexity:* 𝑂(`last - first`) applications each of `unary_op` and
|
| 5518 |
+
`binary_op`.
|
| 5519 |
+
|
| 5520 |
+
[*Note 1*: `transform_reduce` does not apply `unary_op` to
|
| 5521 |
+
`init`. — *end note*]
|
| 5522 |
|
| 5523 |
### Partial sum <a id="partial.sum">[[partial.sum]]</a>
|
| 5524 |
|
| 5525 |
``` cpp
|
| 5526 |
template <class InputIterator, class OutputIterator>
|
| 5527 |
OutputIterator partial_sum(
|
| 5528 |
InputIterator first, InputIterator last,
|
| 5529 |
OutputIterator result);
|
| 5530 |
+
template <class InputIterator, class OutputIterator, class BinaryOperation>
|
|
|
|
| 5531 |
OutputIterator partial_sum(
|
| 5532 |
InputIterator first, InputIterator last,
|
| 5533 |
OutputIterator result, BinaryOperation binary_op);
|
| 5534 |
```
|
| 5535 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5536 |
*Requires:* `InputIterator`’s value type shall be constructible from the
|
| 5537 |
type of `*first`. The result of the expression `acc + *i` or
|
| 5538 |
`binary_op(acc, *i)` shall be implicitly convertible to
|
| 5539 |
+
`InputIterator`’s value type. `acc` shall be
|
| 5540 |
+
writable ([[iterator.requirements.general]]) to the `result` output
|
| 5541 |
+
iterator. In the ranges \[`first`, `last`\] and \[`result`,
|
| 5542 |
+
`result + (last - first)`\] `binary_op` shall neither modify elements
|
| 5543 |
+
nor invalidate iterators or subranges.[^16]
|
| 5544 |
+
|
| 5545 |
+
*Effects:* For a non-empty range, the function creates an accumulator
|
| 5546 |
+
`acc` whose type is `InputIterator`’s value type, initializes it with
|
| 5547 |
+
`*first`, and assigns the result to `*result`. For every iterator `i` in
|
| 5548 |
+
\[`first + 1`, `last`) in order, `acc` is then modified by
|
| 5549 |
+
`acc = acc + *i` or `acc = binary_op(acc, *i)` and the result is
|
| 5550 |
+
assigned to `*(result + (i - first))`.
|
| 5551 |
+
|
| 5552 |
+
*Returns:* `result + (last - first)`.
|
| 5553 |
+
|
| 5554 |
+
*Complexity:* Exactly `(last - first) - 1` applications of the binary
|
| 5555 |
+
operation.
|
| 5556 |
+
|
| 5557 |
+
*Remarks:* `result` may be equal to `first`.
|
| 5558 |
+
|
| 5559 |
+
### Exclusive scan <a id="exclusive.scan">[[exclusive.scan]]</a>
|
| 5560 |
+
|
| 5561 |
+
``` cpp
|
| 5562 |
+
template<class InputIterator, class OutputIterator, class T>
|
| 5563 |
+
OutputIterator exclusive_scan(InputIterator first, InputIterator last,
|
| 5564 |
+
OutputIterator result,
|
| 5565 |
+
T init);
|
| 5566 |
+
```
|
| 5567 |
+
|
| 5568 |
+
*Effects:* Equivalent to:
|
| 5569 |
+
|
| 5570 |
+
``` cpp
|
| 5571 |
+
return exclusive_scan(first, last, result, init, plus<>());
|
| 5572 |
+
```
|
| 5573 |
+
|
| 5574 |
+
``` cpp
|
| 5575 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2, class T>
|
| 5576 |
+
ForwardIterator2 exclusive_scan(ExecutionPolicy&& exec,
|
| 5577 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5578 |
+
ForwardIterator2 result,
|
| 5579 |
+
T init);
|
| 5580 |
+
```
|
| 5581 |
+
|
| 5582 |
+
*Effects:* Equivalent to:
|
| 5583 |
+
|
| 5584 |
+
``` cpp
|
| 5585 |
+
return exclusive_scan(std::forward<ExecutionPolicy>(exec),
|
| 5586 |
+
first, last, result, init, plus<>());
|
| 5587 |
+
```
|
| 5588 |
+
|
| 5589 |
+
``` cpp
|
| 5590 |
+
template<class InputIterator, class OutputIterator, class T, class BinaryOperation>
|
| 5591 |
+
OutputIterator exclusive_scan(InputIterator first, InputIterator last,
|
| 5592 |
+
OutputIterator result,
|
| 5593 |
+
T init, BinaryOperation binary_op);
|
| 5594 |
+
template<class ExecutionPolicy,
|
| 5595 |
+
class ForwardIterator1, class ForwardIterator2, class T, class BinaryOperation>
|
| 5596 |
+
ForwardIterator2 exclusive_scan(ExecutionPolicy&& exec,
|
| 5597 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5598 |
+
ForwardIterator2 result,
|
| 5599 |
+
T init, BinaryOperation binary_op);
|
| 5600 |
+
```
|
| 5601 |
+
|
| 5602 |
+
*Requires:*
|
| 5603 |
+
|
| 5604 |
+
- `T` shall be `MoveConstructible` (Table [[tab:moveconstructible]]).
|
| 5605 |
+
- All of `binary_op(init, init)`, `binary_op(init, *first)`, and
|
| 5606 |
+
`binary_op(*first, *first)` shall be convertible to `T`.
|
| 5607 |
+
- `binary_op` shall neither invalidate iterators or subranges, nor
|
| 5608 |
+
modify elements in the ranges \[`first`, `last`\] or \[`result`,
|
| 5609 |
+
`result + (last - first)`\].
|
| 5610 |
+
|
| 5611 |
+
*Effects:* For each integer `K` in \[`0`, `last - first`) assigns
|
| 5612 |
+
through `result + K` the value of:
|
| 5613 |
+
|
| 5614 |
+
``` cpp
|
| 5615 |
+
GENERALIZED_NONCOMMUTATIVE_SUM(
|
| 5616 |
+
binary_op, init, *(first + 0), *(first + 1), ..., *(first + K - 1))
|
| 5617 |
+
```
|
| 5618 |
+
|
| 5619 |
+
*Returns:* The end of the resulting range beginning at `result`.
|
| 5620 |
+
|
| 5621 |
+
*Complexity:* 𝑂(`last - first`) applications of `binary_op`.
|
| 5622 |
+
|
| 5623 |
+
*Remarks:* `result` may be equal to `first`.
|
| 5624 |
+
|
| 5625 |
+
[*Note 1*: The difference between `exclusive_scan` and `inclusive_scan`
|
| 5626 |
+
is that `exclusive_scan` excludes the `i`th input element from the `i`th
|
| 5627 |
+
sum. If `binary_op` is not mathematically associative, the behavior of
|
| 5628 |
+
`exclusive_scan` may be nondeterministic. — *end note*]
|
| 5629 |
+
|
| 5630 |
+
### Inclusive scan <a id="inclusive.scan">[[inclusive.scan]]</a>
|
| 5631 |
+
|
| 5632 |
+
``` cpp
|
| 5633 |
+
template<class InputIterator, class OutputIterator>
|
| 5634 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5635 |
+
OutputIterator result);
|
| 5636 |
+
```
|
| 5637 |
+
|
| 5638 |
+
*Effects:* Equivalent to:
|
| 5639 |
+
|
| 5640 |
+
``` cpp
|
| 5641 |
+
return inclusive_scan(first, last, result, plus<>());
|
| 5642 |
+
```
|
| 5643 |
+
|
| 5644 |
+
``` cpp
|
| 5645 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
|
| 5646 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec,
|
| 5647 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5648 |
+
ForwardIterator2 result);
|
| 5649 |
+
```
|
| 5650 |
+
|
| 5651 |
+
*Effects:* Equivalent to:
|
| 5652 |
+
|
| 5653 |
+
``` cpp
|
| 5654 |
+
return inclusive_scan(std::forward<ExecutionPolicy>(exec), first, last, result, plus<>());
|
| 5655 |
+
```
|
| 5656 |
+
|
| 5657 |
+
``` cpp
|
| 5658 |
+
template<class InputIterator, class OutputIterator, class BinaryOperation>
|
| 5659 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5660 |
+
OutputIterator result,
|
| 5661 |
+
BinaryOperation binary_op);
|
| 5662 |
+
template<class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
|
| 5663 |
+
class BinaryOperation>
|
| 5664 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec,
|
| 5665 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5666 |
+
ForwardIterator2 result,
|
| 5667 |
+
BinaryOperation binary_op);
|
| 5668 |
+
|
| 5669 |
+
template<class InputIterator, class OutputIterator, class BinaryOperation, class T>
|
| 5670 |
+
OutputIterator inclusive_scan(InputIterator first, InputIterator last,
|
| 5671 |
+
OutputIterator result,
|
| 5672 |
+
BinaryOperation binary_op, T init);
|
| 5673 |
+
template<class ExecutionPolicy,
|
| 5674 |
+
class ForwardIterator1, class ForwardIterator2, class BinaryOperation, class T>
|
| 5675 |
+
ForwardIterator2 inclusive_scan(ExecutionPolicy&& exec,
|
| 5676 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5677 |
+
ForwardIterator2 result,
|
| 5678 |
+
BinaryOperation binary_op, T init);
|
| 5679 |
+
```
|
| 5680 |
+
|
| 5681 |
+
*Requires:*
|
| 5682 |
+
|
| 5683 |
+
- If `init` is provided, `T` shall be `MoveConstructible`
|
| 5684 |
+
(Table [[tab:moveconstructible]]); otherwise, `ForwardIterator1`’s
|
| 5685 |
+
value type shall be `MoveConstructible`.
|
| 5686 |
+
- If `init` is provided, all of `binary_op(init, init)`,
|
| 5687 |
+
`binary_op(init, *first)`, and `binary_op(*first, *first)` shall be
|
| 5688 |
+
convertible to `T`; otherwise, `binary_op(*first, *first)` shall be
|
| 5689 |
+
convertible to `ForwardIterator1`’s value type.
|
| 5690 |
+
- `binary_op` shall neither invalidate iterators or subranges, nor
|
| 5691 |
+
modify elements in the ranges \[`first`, `last`\] or \[`result`,
|
| 5692 |
+
`result + (last - first)`\].
|
| 5693 |
+
|
| 5694 |
+
*Effects:* For each integer `K` in \[`0`, `last - first`) assigns
|
| 5695 |
+
through `result + K` the value of
|
| 5696 |
+
|
| 5697 |
+
- *GENERALIZED_NONCOMMUTATIVE_SUM*(
|
| 5698 |
+
binary_op, init, \*(first + 0), \*(first + 1), ..., \*(first +
|
| 5699 |
+
K))
|
| 5700 |
+
if `init` is provided, or
|
| 5701 |
+
- *GENERALIZED_NONCOMMUTATIVE_SUM*(
|
| 5702 |
+
binary_op, \*(first + 0), \*(first + 1), ..., \*(first + K))
|
| 5703 |
+
otherwise.
|
| 5704 |
+
|
| 5705 |
+
*Returns:* The end of the resulting range beginning at `result`.
|
| 5706 |
+
|
| 5707 |
+
*Complexity:* 𝑂(`last - first`) applications of `binary_op`.
|
| 5708 |
|
| 5709 |
*Remarks:* `result` may be equal to `first`.
|
| 5710 |
|
| 5711 |
+
[*Note 1*: The difference between `exclusive_scan` and `inclusive_scan`
|
| 5712 |
+
is that `inclusive_scan` includes the `i`th input element in the `i`th
|
| 5713 |
+
sum. If `binary_op` is not mathematically associative, the behavior of
|
| 5714 |
+
`inclusive_scan` may be nondeterministic. — *end note*]
|
| 5715 |
+
|
| 5716 |
+
### Transform exclusive scan <a id="transform.exclusive.scan">[[transform.exclusive.scan]]</a>
|
| 5717 |
+
|
| 5718 |
+
``` cpp
|
| 5719 |
+
template<class InputIterator, class OutputIterator, class T,
|
| 5720 |
+
class BinaryOperation, class UnaryOperation>
|
| 5721 |
+
OutputIterator transform_exclusive_scan(InputIterator first, InputIterator last,
|
| 5722 |
+
OutputIterator result,
|
| 5723 |
+
T init,
|
| 5724 |
+
BinaryOperation binary_op,
|
| 5725 |
+
UnaryOperation unary_op);
|
| 5726 |
+
template<class ExecutionPolicy,
|
| 5727 |
+
class ForwardIterator1, class ForwardIterator2, class T,
|
| 5728 |
+
class BinaryOperation, class UnaryOperation>
|
| 5729 |
+
ForwardIterator2 transform_exclusive_scan(ExecutionPolicy&& exec,
|
| 5730 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5731 |
+
ForwardIterator2 result,
|
| 5732 |
+
T init,
|
| 5733 |
+
BinaryOperation binary_op,
|
| 5734 |
+
UnaryOperation unary_op);
|
| 5735 |
+
```
|
| 5736 |
+
|
| 5737 |
+
*Requires:*
|
| 5738 |
+
|
| 5739 |
+
- `T` shall be `MoveConstructible` (Table [[tab:moveconstructible]]).
|
| 5740 |
+
- All of
|
| 5741 |
+
- `binary_op(init, init)`,
|
| 5742 |
+
- `binary_op(init, unary_op(*first))`, and
|
| 5743 |
+
- `binary_op(unary_op(*first), unary_op(*first))`
|
| 5744 |
+
|
| 5745 |
+
shall be convertible to `T`.
|
| 5746 |
+
- Neither `unary_op` nor `binary_op` shall invalidate iterators or
|
| 5747 |
+
subranges, or modify elements in the ranges \[`first`, `last`\] or
|
| 5748 |
+
\[`result`, `result + (last - first)`\].
|
| 5749 |
+
|
| 5750 |
+
*Effects:* For each integer `K` in \[`0`, `last - first`) assigns
|
| 5751 |
+
through `result + K` the value of:
|
| 5752 |
+
|
| 5753 |
+
``` cpp
|
| 5754 |
+
GENERALIZED_NONCOMMUTATIVE_SUM(
|
| 5755 |
+
binary_op, init,
|
| 5756 |
+
unary_op(*(first + 0)), unary_op(*(first + 1)), ..., unary_op(*(first + K - 1)))
|
| 5757 |
+
```
|
| 5758 |
+
|
| 5759 |
+
*Returns:* The end of the resulting range beginning at `result`.
|
| 5760 |
+
|
| 5761 |
+
*Complexity:* 𝑂(`last - first`) applications each of `unary_op` and
|
| 5762 |
+
`binary_op`.
|
| 5763 |
+
|
| 5764 |
+
*Remarks:* `result` may be equal to `first`.
|
| 5765 |
+
|
| 5766 |
+
[*Note 1*: The difference between `transform_exclusive_scan` and
|
| 5767 |
+
`transform_inclusive_scan` is that `transform_exclusive_scan` excludes
|
| 5768 |
+
the iᵗʰ input element from the iᵗʰ sum. If `binary_op` is not
|
| 5769 |
+
mathematically associative, the behavior of `transform_exclusive_scan`
|
| 5770 |
+
may be nondeterministic. `transform_exclusive_scan` does not apply
|
| 5771 |
+
`unary_op` to `init`. — *end note*]
|
| 5772 |
+
|
| 5773 |
+
### Transform inclusive scan <a id="transform.inclusive.scan">[[transform.inclusive.scan]]</a>
|
| 5774 |
+
|
| 5775 |
+
``` cpp
|
| 5776 |
+
template<class InputIterator, class OutputIterator,
|
| 5777 |
+
class BinaryOperation, class UnaryOperation>
|
| 5778 |
+
OutputIterator transform_inclusive_scan(InputIterator first, InputIterator last,
|
| 5779 |
+
OutputIterator result,
|
| 5780 |
+
BinaryOperation binary_op,
|
| 5781 |
+
UnaryOperation unary_op);
|
| 5782 |
+
template<class ExecutionPolicy,
|
| 5783 |
+
class ForwardIterator1, class ForwardIterator2,
|
| 5784 |
+
class BinaryOperation, class UnaryOperation>
|
| 5785 |
+
ForwardIterator2 transform_inclusive_scan(ExecutionPolicy&& exec,
|
| 5786 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5787 |
+
ForwardIterator2 result,
|
| 5788 |
+
BinaryOperation binary_op,
|
| 5789 |
+
UnaryOperation unary_op);
|
| 5790 |
+
template<class InputIterator, class OutputIterator,
|
| 5791 |
+
class BinaryOperation, class UnaryOperation, class T>
|
| 5792 |
+
OutputIterator transform_inclusive_scan(InputIterator first, InputIterator last,
|
| 5793 |
+
OutputIterator result,
|
| 5794 |
+
BinaryOperation binary_op,
|
| 5795 |
+
UnaryOperation unary_op,
|
| 5796 |
+
T init);
|
| 5797 |
+
template<class ExecutionPolicy,
|
| 5798 |
+
class ForwardIterator1, class ForwardIterator2,
|
| 5799 |
+
class BinaryOperation, class UnaryOperation, class T>
|
| 5800 |
+
ForwardIterator2 transform_inclusive_scan(ExecutionPolicy&& exec,
|
| 5801 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5802 |
+
ForwardIterator2 result,
|
| 5803 |
+
BinaryOperation binary_op,
|
| 5804 |
+
UnaryOperation unary_op,
|
| 5805 |
+
T init);
|
| 5806 |
+
```
|
| 5807 |
+
|
| 5808 |
+
*Requires:*
|
| 5809 |
+
|
| 5810 |
+
- If `init` is provided, `T` shall be `MoveConstructible`
|
| 5811 |
+
(Table [[tab:moveconstructible]]); otherwise, `ForwardIterator1`’s
|
| 5812 |
+
value type shall be `MoveConstructible`.
|
| 5813 |
+
- If `init` is provided, all of
|
| 5814 |
+
- `binary_op(init, init)`,
|
| 5815 |
+
- `binary_op(init, unary_op(*first))`, and
|
| 5816 |
+
- `binary_op(unary_op(*first), unary_op(*first))`
|
| 5817 |
+
|
| 5818 |
+
shall be convertible to `T`; otherwise,
|
| 5819 |
+
`binary_op(unary_op(*first), unary_op(*first))` shall be convertible
|
| 5820 |
+
to `ForwardIterator1`’s value type.
|
| 5821 |
+
- Neither `unary_op` nor `binary_op` shall invalidate iterators or
|
| 5822 |
+
subranges, nor modify elements in the ranges \[`first`, `last`\] or
|
| 5823 |
+
\[`result`, `result + (last - first)`\].
|
| 5824 |
+
|
| 5825 |
+
*Effects:* For each integer `K` in \[`0`, `last - first`) assigns
|
| 5826 |
+
through `result + K` the value of
|
| 5827 |
+
|
| 5828 |
+
- *GENERALIZED_NONCOMMUTATIVE_SUM*(
|
| 5829 |
+
binary_op, init,
|
| 5830 |
+
unary_op(\*(first + 0)), unary_op(\*(first + 1)), ...,
|
| 5831 |
+
unary_op(\*(first + K)))
|
| 5832 |
+
if `init` is provided, or
|
| 5833 |
+
- *GENERALIZED_NONCOMMUTATIVE_SUM*(
|
| 5834 |
+
binary_op,
|
| 5835 |
+
unary_op(\*(first + 0)), unary_op(\*(first + 1)), ...,
|
| 5836 |
+
unary_op(\*(first + K)))
|
| 5837 |
+
otherwise.
|
| 5838 |
+
|
| 5839 |
+
*Returns:* The end of the resulting range beginning at `result`.
|
| 5840 |
+
|
| 5841 |
+
*Complexity:* 𝑂(`last - first`) applications each of `unary_op` and
|
| 5842 |
+
`binary_op`.
|
| 5843 |
+
|
| 5844 |
+
*Remarks:* `result` may be equal to `first`.
|
| 5845 |
+
|
| 5846 |
+
[*Note 1*: The difference between `transform_exclusive_scan` and
|
| 5847 |
+
`transform_inclusive_scan` is that `transform_inclusive_scan` includes
|
| 5848 |
+
the iᵗʰ input element in the iᵗʰ sum. If `binary_op` is not
|
| 5849 |
+
mathematically associative, the behavior of `transform_inclusive_scan`
|
| 5850 |
+
may be nondeterministic. `transform_inclusive_scan` does not apply
|
| 5851 |
+
`unary_op` to `init`. — *end note*]
|
| 5852 |
+
|
| 5853 |
### Adjacent difference <a id="adjacent.difference">[[adjacent.difference]]</a>
|
| 5854 |
|
| 5855 |
``` cpp
|
| 5856 |
template <class InputIterator, class OutputIterator>
|
| 5857 |
+
OutputIterator
|
| 5858 |
+
adjacent_difference(InputIterator first, InputIterator last,
|
| 5859 |
OutputIterator result);
|
| 5860 |
+
template <class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2>
|
| 5861 |
+
ForwardIterator2
|
| 5862 |
+
adjacent_difference(ExecutionPolicy&& exec,
|
| 5863 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5864 |
+
ForwardIterator2 result);
|
| 5865 |
+
|
| 5866 |
template <class InputIterator, class OutputIterator, class BinaryOperation>
|
| 5867 |
+
OutputIterator
|
| 5868 |
+
adjacent_difference(InputIterator first, InputIterator last,
|
| 5869 |
OutputIterator result,
|
| 5870 |
BinaryOperation binary_op);
|
| 5871 |
+
template <class ExecutionPolicy, class ForwardIterator1, class ForwardIterator2,
|
| 5872 |
+
class BinaryOperation>
|
| 5873 |
+
ForwardIterator2
|
| 5874 |
+
adjacent_difference(ExecutionPolicy&& exec,
|
| 5875 |
+
ForwardIterator1 first, ForwardIterator1 last,
|
| 5876 |
+
ForwardIterator2 result,
|
| 5877 |
+
BinaryOperation binary_op);
|
| 5878 |
```
|
| 5879 |
|
| 5880 |
+
*Requires:*
|
| 5881 |
+
|
| 5882 |
+
- For the overloads with no `ExecutionPolicy`, `InputIterator`’s value
|
| 5883 |
+
type shall be `MoveAssignable` (Table [[tab:moveassignable]]) and
|
| 5884 |
+
shall be constructible from the type of `*first`. `acc` (defined
|
| 5885 |
+
below) shall be writable ([[iterator.requirements.general]]) to the
|
| 5886 |
+
`result` output iterator. The result of the expression `val - acc` or
|
| 5887 |
+
`binary_op(val, acc)` shall be writable to the `result` output
|
| 5888 |
+
iterator.
|
| 5889 |
+
- For the overloads with an `ExecutionPolicy`, the value type of
|
| 5890 |
+
`ForwardIterator1` shall be `CopyConstructible`
|
| 5891 |
+
(Table [[tab:copyconstructible]]), constructible from the expression
|
| 5892 |
+
`*first - *first` or `binary_op(*first, *first)`, and assignable to
|
| 5893 |
+
the value type of `ForwardIterator2`.
|
| 5894 |
+
- For all overloads, in the ranges \[`first`, `last`\] and \[`result`,
|
| 5895 |
+
`result + (last - first)`\], `binary_op` shall neither modify elements
|
| 5896 |
+
nor invalidate iterators or subranges.[^17]
|
| 5897 |
+
|
| 5898 |
+
*Effects:* For the overloads with no `ExecutionPolicy` and a non-empty
|
| 5899 |
+
range, the function creates an accumulator `acc` whose type is
|
| 5900 |
+
`InputIterator`’s value type, initializes it with `*first`, and assigns
|
| 5901 |
+
the result to `*result`. For every iterator `i` in \[`first + 1`,
|
| 5902 |
+
`last`) in order, creates an object `val` whose type is
|
| 5903 |
`InputIterator`’s value type, initializes it with `*i`, computes
|
| 5904 |
`val - acc` or `binary_op(val, acc)`, assigns the result to
|
| 5905 |
`*(result + (i - first))`, and move assigns from `val` to `acc`.
|
| 5906 |
|
| 5907 |
+
For the overloads with an `ExecutionPolicy` and a non-empty range, first
|
| 5908 |
+
the function creates an object whose type is `ForwardIterator1`’s value
|
| 5909 |
+
type, initializes it with `*first`, and assigns the result to `*result`.
|
| 5910 |
+
Then for every `d` in \[`1`, `last - first - 1`\], creates an object
|
| 5911 |
+
`val` whose type is `ForwardIterator1`’s value type, initializes it with
|
| 5912 |
+
`*(first + d) - *(first + d - 1)` or
|
| 5913 |
+
`binary_op(*(first + d), *(first + d - 1))`, and assigns the result to
|
| 5914 |
+
`*(result + d)`.
|
|
|
|
| 5915 |
|
| 5916 |
*Returns:* `result + (last - first)`.
|
| 5917 |
|
| 5918 |
*Complexity:* Exactly `(last - first) - 1` applications of the binary
|
| 5919 |
operation.
|
| 5920 |
|
| 5921 |
+
*Remarks:* For the overloads with no `ExecutionPolicy`, `result` may be
|
| 5922 |
+
equal to `first`. For the overloads with an `ExecutionPolicy`, the
|
| 5923 |
+
ranges \[`first`, `last`) and \[`result`, `result + (last - first)`)
|
| 5924 |
+
shall not overlap.
|
| 5925 |
+
|
| 5926 |
### Iota <a id="numeric.iota">[[numeric.iota]]</a>
|
| 5927 |
|
| 5928 |
``` cpp
|
| 5929 |
template <class ForwardIterator, class T>
|
| 5930 |
void iota(ForwardIterator first, ForwardIterator last, T value);
|
|
|
|
| 5937 |
\[`first`, `last`), assigns `*i = value` and increments `value` as if by
|
| 5938 |
`++value`.
|
| 5939 |
|
| 5940 |
*Complexity:* Exactly `last - first` increments and assignments.
|
| 5941 |
|
| 5942 |
+
### Greatest common divisor <a id="numeric.ops.gcd">[[numeric.ops.gcd]]</a>
|
| 5943 |
|
| 5944 |
+
``` cpp
|
| 5945 |
+
template <class M, class N>
|
| 5946 |
+
constexpr common_type_t<M,N> gcd(M m, N n);
|
| 5947 |
+
```
|
| 5948 |
|
| 5949 |
+
*Requires:* `|m|` and `|n|` shall be representable as a value of
|
| 5950 |
+
`common_type_t<M, N>`.
|
| 5951 |
|
| 5952 |
+
[*Note 1*: These requirements ensure, for example, that
|
| 5953 |
+
`gcd(m, m) = |m|` is representable as a value of type
|
| 5954 |
+
`M`. — *end note*]
|
| 5955 |
|
| 5956 |
+
*Remarks:* If either `M` or `N` is not an integer type, or if either is
|
| 5957 |
+
cv `bool`, the program is ill-formed.
|
|
|
|
| 5958 |
|
| 5959 |
+
*Returns:* Zero when `m` and `n` are both zero. Otherwise, returns the
|
| 5960 |
+
greatest common divisor of `|m|` and `|n|`.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5961 |
|
| 5962 |
+
*Throws:* Nothing.
|
|
|
|
|
|
|
| 5963 |
|
| 5964 |
+
### Least common multiple <a id="numeric.ops.lcm">[[numeric.ops.lcm]]</a>
|
| 5965 |
|
| 5966 |
``` cpp
|
| 5967 |
+
template <class M, class N>
|
| 5968 |
+
constexpr common_type_t<M,N> lcm(M m, N n);
|
|
|
|
|
|
|
| 5969 |
```
|
| 5970 |
|
| 5971 |
+
*Requires:* `|m|` and `|n|` shall be representable as a value of
|
| 5972 |
+
`common_type_t<M, N>`. The least common multiple of `|m|` and `|n|`
|
| 5973 |
+
shall be representable as a value of type `common_type_t<M,N>`.
|
| 5974 |
|
| 5975 |
+
*Remarks:* If either `M` or `N` is not an integer type, or if either is
|
| 5976 |
+
cv `bool` the program is ill-formed.
|
| 5977 |
|
| 5978 |
+
*Returns:* Zero when either `m` or `n` is zero. Otherwise, returns the
|
| 5979 |
+
least common multiple of `|m|` and `|n|`.
|
| 5980 |
+
|
| 5981 |
+
*Throws:* Nothing.
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 5982 |
|
| 5983 |
+
## Mathematical functions for floating-point types <a id="c.math">[[c.math]]</a>
|
| 5984 |
+
|
| 5985 |
+
### Header `<cmath>` synopsis <a id="cmath.syn">[[cmath.syn]]</a>
|
|
|
|
| 5986 |
|
| 5987 |
``` cpp
|
| 5988 |
+
namespace std {
|
| 5989 |
+
using float_t = see below;
|
| 5990 |
+
using double_t = see below;
|
| 5991 |
+
}
|
| 5992 |
+
|
| 5993 |
+
#define HUGE_VAL see below
|
| 5994 |
+
#define HUGE_VALF see below
|
| 5995 |
+
#define HUGE_VALL see below
|
| 5996 |
+
#define INFINITY see below
|
| 5997 |
+
#define NAN see below
|
| 5998 |
+
#define FP_INFINITE see below
|
| 5999 |
+
#define FP_NAN see below
|
| 6000 |
+
#define FP_NORMAL see below
|
| 6001 |
+
#define FP_SUBNORMAL see below
|
| 6002 |
+
#define FP_ZERO see below
|
| 6003 |
+
#define FP_FAST_FMA see below
|
| 6004 |
+
#define FP_FAST_FMAF see below
|
| 6005 |
+
#define FP_FAST_FMAL see below
|
| 6006 |
+
#define FP_ILOGB0 see below
|
| 6007 |
+
#define FP_ILOGBNAN see below
|
| 6008 |
+
#define MATH_ERRNO see below
|
| 6009 |
+
#define MATH_ERREXCEPT see below
|
| 6010 |
+
|
| 6011 |
+
#define math_errhandling see below
|
| 6012 |
+
|
| 6013 |
+
namespace std {
|
| 6014 |
+
float acos(float x); // see [library.c]
|
| 6015 |
+
double acos(double x);
|
| 6016 |
+
long double acos(long double x); // see [library.c]
|
| 6017 |
+
float acosf(float x);
|
| 6018 |
+
long double acosl(long double x);
|
| 6019 |
+
|
| 6020 |
+
float asin(float x); // see [library.c]
|
| 6021 |
+
double asin(double x);
|
| 6022 |
+
long double asin(long double x); // see [library.c]
|
| 6023 |
+
float asinf(float x);
|
| 6024 |
+
long double asinl(long double x);
|
| 6025 |
+
|
| 6026 |
+
float atan(float x); // see [library.c]
|
| 6027 |
+
double atan(double x);
|
| 6028 |
+
long double atan(long double x); // see [library.c]
|
| 6029 |
+
float atanf(float x);
|
| 6030 |
+
long double atanl(long double x);
|
| 6031 |
+
|
| 6032 |
+
float atan2(float y, float x); // see [library.c]
|
| 6033 |
+
double atan2(double y, double x);
|
| 6034 |
+
long double atan2(long double y, long double x); // see [library.c]
|
| 6035 |
+
float atan2f(float y, float x);
|
| 6036 |
+
long double atan2l(long double y, long double x);
|
| 6037 |
+
|
| 6038 |
+
float cos(float x); // see [library.c]
|
| 6039 |
+
double cos(double x);
|
| 6040 |
+
long double cos(long double x); // see [library.c]
|
| 6041 |
+
float cosf(float x);
|
| 6042 |
+
long double cosl(long double x);
|
| 6043 |
+
|
| 6044 |
+
float sin(float x); // see [library.c]
|
| 6045 |
+
double sin(double x);
|
| 6046 |
+
long double sin(long double x); // see [library.c]
|
| 6047 |
+
float sinf(float x);
|
| 6048 |
+
long double sinl(long double x);
|
| 6049 |
+
|
| 6050 |
+
float tan(float x); // see [library.c]
|
| 6051 |
+
double tan(double x);
|
| 6052 |
+
long double tan(long double x); // see [library.c]
|
| 6053 |
+
float tanf(float x);
|
| 6054 |
+
long double tanl(long double x);
|
| 6055 |
+
|
| 6056 |
+
float acosh(float x); // see [library.c]
|
| 6057 |
+
double acosh(double x);
|
| 6058 |
+
long double acosh(long double x); // see [library.c]
|
| 6059 |
+
float acoshf(float x);
|
| 6060 |
+
long double acoshl(long double x);
|
| 6061 |
+
|
| 6062 |
+
float asinh(float x); // see [library.c]
|
| 6063 |
+
double asinh(double x);
|
| 6064 |
+
long double asinh(long double x); // see [library.c]
|
| 6065 |
+
float asinhf(float x);
|
| 6066 |
+
long double asinhl(long double x);
|
| 6067 |
+
|
| 6068 |
+
float atanh(float x); // see [library.c]
|
| 6069 |
+
double atanh(double x);
|
| 6070 |
+
long double atanh(long double x); // see [library.c]
|
| 6071 |
+
float atanhf(float x);
|
| 6072 |
+
long double atanhl(long double x);
|
| 6073 |
+
|
| 6074 |
+
float cosh(float x); // see [library.c]
|
| 6075 |
+
double cosh(double x);
|
| 6076 |
+
long double cosh(long double x); // see [library.c]
|
| 6077 |
+
float coshf(float x);
|
| 6078 |
+
long double coshl(long double x);
|
| 6079 |
+
|
| 6080 |
+
float sinh(float x); // see [library.c]
|
| 6081 |
+
double sinh(double x);
|
| 6082 |
+
long double sinh(long double x); // see [library.c]
|
| 6083 |
+
float sinhf(float x);
|
| 6084 |
+
long double sinhl(long double x);
|
| 6085 |
+
|
| 6086 |
+
float tanh(float x); // see [library.c]
|
| 6087 |
+
double tanh(double x);
|
| 6088 |
+
long double tanh(long double x); // see [library.c]
|
| 6089 |
+
float tanhf(float x);
|
| 6090 |
+
long double tanhl(long double x);
|
| 6091 |
+
|
| 6092 |
+
float exp(float x); // see [library.c]
|
| 6093 |
+
double exp(double x);
|
| 6094 |
+
long double exp(long double x); // see [library.c]
|
| 6095 |
+
float expf(float x);
|
| 6096 |
+
long double expl(long double x);
|
| 6097 |
+
|
| 6098 |
+
float exp2(float x); // see [library.c]
|
| 6099 |
+
double exp2(double x);
|
| 6100 |
+
long double exp2(long double x); // see [library.c]
|
| 6101 |
+
float exp2f(float x);
|
| 6102 |
+
long double exp2l(long double x);
|
| 6103 |
+
|
| 6104 |
+
float expm1(float x); // see [library.c]
|
| 6105 |
+
double expm1(double x);
|
| 6106 |
+
long double expm1(long double x); // see [library.c]
|
| 6107 |
+
float expm1f(float x);
|
| 6108 |
+
long double expm1l(long double x);
|
| 6109 |
+
|
| 6110 |
+
float frexp(float value, int* exp); // see [library.c]
|
| 6111 |
+
double frexp(double value, int* exp);
|
| 6112 |
+
long double frexp(long double value, int* exp); // see [library.c]
|
| 6113 |
+
float frexpf(float value, int* exp);
|
| 6114 |
+
long double frexpl(long double value, int* exp);
|
| 6115 |
+
|
| 6116 |
+
int ilogb(float x); // see [library.c]
|
| 6117 |
+
int ilogb(double x);
|
| 6118 |
+
int ilogb(long double x); // see [library.c]
|
| 6119 |
+
int ilogbf(float x);
|
| 6120 |
+
int ilogbl(long double x);
|
| 6121 |
+
|
| 6122 |
+
float ldexp(float x, int exp); // see [library.c]
|
| 6123 |
+
double ldexp(double x, int exp);
|
| 6124 |
+
long double ldexp(long double x, int exp); // see [library.c]
|
| 6125 |
+
float ldexpf(float x, int exp);
|
| 6126 |
+
long double ldexpl(long double x, int exp);
|
| 6127 |
+
|
| 6128 |
+
float log(float x); // see [library.c]
|
| 6129 |
+
double log(double x);
|
| 6130 |
+
long double log(long double x); // see [library.c]
|
| 6131 |
+
float logf(float x);
|
| 6132 |
+
long double logl(long double x);
|
| 6133 |
+
|
| 6134 |
+
float log10(float x); // see [library.c]
|
| 6135 |
+
double log10(double x);
|
| 6136 |
+
long double log10(long double x); // see [library.c]
|
| 6137 |
+
float log10f(float x);
|
| 6138 |
+
long double log10l(long double x);
|
| 6139 |
+
|
| 6140 |
+
float log1p(float x); // see [library.c]
|
| 6141 |
+
double log1p(double x);
|
| 6142 |
+
long double log1p(long double x); // see [library.c]
|
| 6143 |
+
float log1pf(float x);
|
| 6144 |
+
long double log1pl(long double x);
|
| 6145 |
+
|
| 6146 |
+
float log2(float x); // see [library.c]
|
| 6147 |
+
double log2(double x);
|
| 6148 |
+
long double log2(long double x); // see [library.c]
|
| 6149 |
+
float log2f(float x);
|
| 6150 |
+
long double log2l(long double x);
|
| 6151 |
+
|
| 6152 |
+
float logb(float x); // see [library.c]
|
| 6153 |
+
double logb(double x);
|
| 6154 |
+
long double logb(long double x); // see [library.c]
|
| 6155 |
+
float logbf(float x);
|
| 6156 |
+
long double logbl(long double x);
|
| 6157 |
+
|
| 6158 |
+
float modf(float value, float* iptr); // see [library.c]
|
| 6159 |
+
double modf(double value, double* iptr);
|
| 6160 |
+
long double modf(long double value, long double* iptr); // see [library.c]
|
| 6161 |
+
float modff(float value, float* iptr);
|
| 6162 |
+
long double modfl(long double value, long double* iptr);
|
| 6163 |
+
|
| 6164 |
+
float scalbn(float x, int n); // see [library.c]
|
| 6165 |
+
double scalbn(double x, int n);
|
| 6166 |
+
long double scalbn(long double x, int n); // see [library.c]
|
| 6167 |
+
float scalbnf(float x, int n);
|
| 6168 |
+
long double scalbnl(long double x, int n);
|
| 6169 |
+
|
| 6170 |
+
float scalbln(float x, long int n); // see [library.c]
|
| 6171 |
+
double scalbln(double x, long int n);
|
| 6172 |
+
long double scalbln(long double x, long int n); // see [library.c]
|
| 6173 |
+
float scalblnf(float x, long int n);
|
| 6174 |
+
long double scalblnl(long double x, long int n);
|
| 6175 |
+
|
| 6176 |
+
float cbrt(float x); // see [library.c]
|
| 6177 |
+
double cbrt(double x);
|
| 6178 |
+
long double cbrt(long double x); // see [library.c]
|
| 6179 |
+
float cbrtf(float x);
|
| 6180 |
+
long double cbrtl(long double x);
|
| 6181 |
+
|
| 6182 |
+
// [c.math.abs], absolute values
|
| 6183 |
+
int abs(int j);
|
| 6184 |
+
long int abs(long int j);
|
| 6185 |
+
long long int abs(long long int j);
|
| 6186 |
+
float abs(float j);
|
| 6187 |
+
double abs(double j);
|
| 6188 |
+
long double abs(long double j);
|
| 6189 |
+
|
| 6190 |
+
float fabs(float x); // see [library.c]
|
| 6191 |
+
double fabs(double x);
|
| 6192 |
+
long double fabs(long double x); // see [library.c]
|
| 6193 |
+
float fabsf(float x);
|
| 6194 |
+
long double fabsl(long double x);
|
| 6195 |
+
|
| 6196 |
+
float hypot(float x, float y); // see [library.c]
|
| 6197 |
+
double hypot(double x, double y);
|
| 6198 |
+
long double hypot(double x, double y); // see [library.c]
|
| 6199 |
+
float hypotf(float x, float y);
|
| 6200 |
+
long double hypotl(long double x, long double y);
|
| 6201 |
+
|
| 6202 |
+
// [c.math.hypot3], three-dimensional hypotenuse
|
| 6203 |
+
float hypot(float x, float y, float z);
|
| 6204 |
+
double hypot(double x, double y, double z);
|
| 6205 |
+
long double hypot(long double x, long double y, long double z);
|
| 6206 |
+
|
| 6207 |
+
float pow(float x, float y); // see [library.c]
|
| 6208 |
+
double pow(double x, double y);
|
| 6209 |
+
long double pow(long double x, long double y); // see [library.c]
|
| 6210 |
+
float powf(float x, float y);
|
| 6211 |
+
long double powl(long double x, long double y);
|
| 6212 |
+
|
| 6213 |
+
float sqrt(float x); // see [library.c]
|
| 6214 |
+
double sqrt(double x);
|
| 6215 |
+
long double sqrt(long double x); // see [library.c]
|
| 6216 |
+
float sqrtf(float x);
|
| 6217 |
+
long double sqrtl(long double x);
|
| 6218 |
+
|
| 6219 |
+
float erf(float x); // see [library.c]
|
| 6220 |
+
double erf(double x);
|
| 6221 |
+
long double erf(long double x); // see [library.c]
|
| 6222 |
+
float erff(float x);
|
| 6223 |
+
long double erfl(long double x);
|
| 6224 |
+
|
| 6225 |
+
float erfc(float x); // see [library.c]
|
| 6226 |
+
double erfc(double x);
|
| 6227 |
+
long double erfc(long double x); // see [library.c]
|
| 6228 |
+
float erfcf(float x);
|
| 6229 |
+
long double erfcl(long double x);
|
| 6230 |
+
|
| 6231 |
+
float lgamma(float x); // see [library.c]
|
| 6232 |
+
double lgamma(double x);
|
| 6233 |
+
long double lgamma(long double x); // see [library.c]
|
| 6234 |
+
float lgammaf(float x);
|
| 6235 |
+
long double lgammal(long double x);
|
| 6236 |
+
|
| 6237 |
+
float tgamma(float x); // see [library.c]
|
| 6238 |
+
double tgamma(double x);
|
| 6239 |
+
long double tgamma(long double x); // see [library.c]
|
| 6240 |
+
float tgammaf(float x);
|
| 6241 |
+
long double tgammal(long double x);
|
| 6242 |
+
|
| 6243 |
+
float ceil(float x); // see [library.c]
|
| 6244 |
+
double ceil(double x);
|
| 6245 |
+
long double ceil(long double x); // see [library.c]
|
| 6246 |
+
float ceilf(float x);
|
| 6247 |
+
long double ceill(long double x);
|
| 6248 |
+
|
| 6249 |
+
float floor(float x); // see [library.c]
|
| 6250 |
+
double floor(double x);
|
| 6251 |
+
long double floor(long double x); // see [library.c]
|
| 6252 |
+
float floorf(float x);
|
| 6253 |
+
long double floorl(long double x);
|
| 6254 |
+
|
| 6255 |
+
float nearbyint(float x); // see [library.c]
|
| 6256 |
+
double nearbyint(double x);
|
| 6257 |
+
long double nearbyint(long double x); // see [library.c]
|
| 6258 |
+
float nearbyintf(float x);
|
| 6259 |
+
long double nearbyintl(long double x);
|
| 6260 |
+
|
| 6261 |
+
float rint(float x); // see [library.c]
|
| 6262 |
+
double rint(double x);
|
| 6263 |
+
long double rint(long double x); // see [library.c]
|
| 6264 |
+
float rintf(float x);
|
| 6265 |
+
long double rintl(long double x);
|
| 6266 |
+
|
| 6267 |
+
long int lrint(float x); // see [library.c]
|
| 6268 |
+
long int lrint(double x);
|
| 6269 |
+
long int lrint(long double x); // see [library.c]
|
| 6270 |
+
long int lrintf(float x);
|
| 6271 |
+
long int lrintl(long double x);
|
| 6272 |
+
|
| 6273 |
+
long long int llrint(float x); // see [library.c]
|
| 6274 |
+
long long int llrint(double x);
|
| 6275 |
+
long long int llrint(long double x); // see [library.c]
|
| 6276 |
+
long long int llrintf(float x);
|
| 6277 |
+
long long int llrintl(long double x);
|
| 6278 |
+
|
| 6279 |
+
float round(float x); // see [library.c]
|
| 6280 |
+
double round(double x);
|
| 6281 |
+
long double round(long double x); // see [library.c]
|
| 6282 |
+
float roundf(float x);
|
| 6283 |
+
long double roundl(long double x);
|
| 6284 |
+
|
| 6285 |
+
long int lround(float x); // see [library.c]
|
| 6286 |
+
long int lround(double x);
|
| 6287 |
+
long int lround(long double x); // see [library.c]
|
| 6288 |
+
long int lroundf(float x);
|
| 6289 |
+
long int lroundl(long double x);
|
| 6290 |
+
|
| 6291 |
+
long long int llround(float x); // see [library.c]
|
| 6292 |
+
long long int llround(double x);
|
| 6293 |
+
long long int llround(long double x); // see [library.c]
|
| 6294 |
+
long long int llroundf(float x);
|
| 6295 |
+
long long int llroundl(long double x);
|
| 6296 |
+
|
| 6297 |
+
float trunc(float x); // see [library.c]
|
| 6298 |
+
double trunc(double x);
|
| 6299 |
+
long double trunc(long double x); // see [library.c]
|
| 6300 |
+
float truncf(float x);
|
| 6301 |
+
long double truncl(long double x);
|
| 6302 |
+
|
| 6303 |
+
float fmod(float x, float y); // see [library.c]
|
| 6304 |
+
double fmod(double x, double y);
|
| 6305 |
+
long double fmod(long double x, long double y); // see [library.c]
|
| 6306 |
+
float fmodf(float x, float y);
|
| 6307 |
+
long double fmodl(long double x, long double y);
|
| 6308 |
+
|
| 6309 |
+
float remainder(float x, float y); // see [library.c]
|
| 6310 |
+
double remainder(double x, double y);
|
| 6311 |
+
long double remainder(long double x, long double y); // see [library.c]
|
| 6312 |
+
float remainderf(float x, float y);
|
| 6313 |
+
long double remainderl(long double x, long double y);
|
| 6314 |
+
|
| 6315 |
+
float remquo(float x, float y, int* quo); // see [library.c]
|
| 6316 |
+
double remquo(double x, double y, int* quo);
|
| 6317 |
+
long double remquo(long double x, long double y, int* quo); // see [library.c]
|
| 6318 |
+
float remquof(float x, float y, int* quo);
|
| 6319 |
+
long double remquol(long double x, long double y, int* quo);
|
| 6320 |
+
|
| 6321 |
+
float copysign(float x, float y); // see [library.c]
|
| 6322 |
+
double copysign(double x, double y);
|
| 6323 |
+
long double copysign(long double x, long double y); // see [library.c]
|
| 6324 |
+
float copysignf(float x, float y);
|
| 6325 |
+
long double copysignl(long double x, long double y);
|
| 6326 |
+
|
| 6327 |
+
double nan(const char* tagp);
|
| 6328 |
+
float nanf(const char* tagp);
|
| 6329 |
+
long double nanl(const char* tagp);
|
| 6330 |
+
|
| 6331 |
+
float nextafter(float x, float y); // see [library.c]
|
| 6332 |
+
double nextafter(double x, double y);
|
| 6333 |
+
long double nextafter(long double x, long double y); // see [library.c]
|
| 6334 |
+
float nextafterf(float x, float y);
|
| 6335 |
+
long double nextafterl(long double x, long double y);
|
| 6336 |
+
|
| 6337 |
+
float nexttoward(float x, long double y); // see [library.c]
|
| 6338 |
+
double nexttoward(double x, long double y);
|
| 6339 |
+
long double nexttoward(long double x, long double y); // see [library.c]
|
| 6340 |
+
float nexttowardf(float x, long double y);
|
| 6341 |
+
long double nexttowardl(long double x, long double y);
|
| 6342 |
+
|
| 6343 |
+
float fdim(float x, float y); // see [library.c]
|
| 6344 |
+
double fdim(double x, double y);
|
| 6345 |
+
long double fdim(long double x, long double y); // see [library.c]
|
| 6346 |
+
float fdimf(float x, float y);
|
| 6347 |
+
long double fdiml(long double x, long double y);
|
| 6348 |
+
|
| 6349 |
+
float fmax(float x, float y); // see [library.c]
|
| 6350 |
+
double fmax(double x, double y);
|
| 6351 |
+
long double fmax(long double x, long double y); // see [library.c]
|
| 6352 |
+
float fmaxf(float x, float y);
|
| 6353 |
+
long double fmaxl(long double x, long double y);
|
| 6354 |
+
|
| 6355 |
+
float fmin(float x, float y); // see [library.c]
|
| 6356 |
+
double fmin(double x, double y);
|
| 6357 |
+
long double fmin(long double x, long double y); // see [library.c]
|
| 6358 |
+
float fminf(float x, float y);
|
| 6359 |
+
long double fminl(long double x, long double y);
|
| 6360 |
+
|
| 6361 |
+
float fma(float x, float y, float z); // see [library.c]
|
| 6362 |
+
double fma(double x, double y, double z);
|
| 6363 |
+
long double fma(long double x, long double y, long double z); // see [library.c]
|
| 6364 |
+
float fmaf(float x, float y, float z);
|
| 6365 |
+
long double fmal(long double x, long double y, long double z);
|
| 6366 |
+
|
| 6367 |
+
// [c.math.fpclass], classification / comparison functions
|
| 6368 |
int fpclassify(float x);
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 6369 |
int fpclassify(double x);
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 6370 |
int fpclassify(long double x);
|
| 6371 |
+
|
| 6372 |
+
int isfinite(float x);
|
| 6373 |
+
int isfinite(double x);
|
| 6374 |
+
int isfinite(long double x);
|
| 6375 |
+
|
| 6376 |
+
int isinf(float x);
|
| 6377 |
+
int isinf(double x);
|
| 6378 |
+
int isinf(long double x);
|
| 6379 |
+
|
| 6380 |
+
int isnan(float x);
|
| 6381 |
+
int isnan(double x);
|
| 6382 |
+
int isnan(long double x);
|
| 6383 |
+
|
| 6384 |
+
int isnormal(float x);
|
| 6385 |
+
int isnormal(double x);
|
| 6386 |
+
int isnormal(long double x);
|
| 6387 |
+
|
| 6388 |
+
int signbit(float x);
|
| 6389 |
+
int signbit(double x);
|
| 6390 |
+
int signbit(long double x);
|
| 6391 |
+
|
| 6392 |
+
int isgreater(float x, float y);
|
| 6393 |
+
int isgreater(double x, double y);
|
| 6394 |
+
int isgreater(long double x, long double y);
|
| 6395 |
+
|
| 6396 |
+
int isgreaterequal(float x, float y);
|
| 6397 |
+
int isgreaterequal(double x, double y);
|
| 6398 |
+
int isgreaterequal(long double x, long double y);
|
| 6399 |
+
|
| 6400 |
+
int isless(float x, float y);
|
| 6401 |
+
int isless(double x, double y);
|
| 6402 |
+
int isless(long double x, long double y);
|
| 6403 |
+
|
| 6404 |
+
int islessequal(float x, float y);
|
| 6405 |
+
int islessequal(double x, double y);
|
| 6406 |
+
int islessequal(long double x, long double y);
|
| 6407 |
+
|
| 6408 |
+
int islessgreater(float x, float y);
|
| 6409 |
+
int islessgreater(double x, double y);
|
| 6410 |
+
int islessgreater(long double x, long double y);
|
| 6411 |
+
|
| 6412 |
+
int isunordered(float x, float y);
|
| 6413 |
+
int isunordered(double x, double y);
|
| 6414 |
+
int isunordered(long double x, long double y);
|
| 6415 |
+
|
| 6416 |
+
// [sf.cmath], mathematical special functions
|
| 6417 |
+
|
| 6418 |
+
// [sf.cmath.assoc_laguerre], associated Laguerre polynomials
|
| 6419 |
+
double assoc_laguerre(unsigned n, unsigned m, double x);
|
| 6420 |
+
float assoc_laguerref(unsigned n, unsigned m, float x);
|
| 6421 |
+
long double assoc_laguerrel(unsigned n, unsigned m, long double x);
|
| 6422 |
+
|
| 6423 |
+
// [sf.cmath.assoc_legendre], associated Legendre functions
|
| 6424 |
+
double assoc_legendre(unsigned l, unsigned m, double x);
|
| 6425 |
+
float assoc_legendref(unsigned l, unsigned m, float x);
|
| 6426 |
+
long double assoc_legendrel(unsigned l, unsigned m, long double x);
|
| 6427 |
+
|
| 6428 |
+
// [sf.cmath.beta], beta function
|
| 6429 |
+
double beta(double x, double y);
|
| 6430 |
+
float betaf(float x, float y);
|
| 6431 |
+
long double betal(long double x, long double y);
|
| 6432 |
+
|
| 6433 |
+
// [sf.cmath.comp_ellint_1], complete elliptic integral of the first kind
|
| 6434 |
+
double comp_ellint_1(double k);
|
| 6435 |
+
float comp_ellint_1f(float k);
|
| 6436 |
+
long double comp_ellint_1l(long double k);
|
| 6437 |
+
|
| 6438 |
+
// [sf.cmath.comp_ellint_2], complete elliptic integral of the second kind
|
| 6439 |
+
double comp_ellint_2(double k);
|
| 6440 |
+
float comp_ellint_2f(float k);
|
| 6441 |
+
long double comp_ellint_2l(long double k);
|
| 6442 |
+
|
| 6443 |
+
// [sf.cmath.comp_ellint_3], complete elliptic integral of the third kind
|
| 6444 |
+
double comp_ellint_3(double k, double nu);
|
| 6445 |
+
float comp_ellint_3f(float k, float nu);
|
| 6446 |
+
long double comp_ellint_3l(long double k, long double nu);
|
| 6447 |
+
|
| 6448 |
+
// [sf.cmath.cyl_bessel_i], regular modified cylindrical Bessel functions
|
| 6449 |
+
double cyl_bessel_i(double nu, double x);
|
| 6450 |
+
float cyl_bessel_if(float nu, float x);
|
| 6451 |
+
long double cyl_bessel_il(long double nu, long double x);
|
| 6452 |
+
|
| 6453 |
+
// [sf.cmath.cyl_bessel_j], cylindrical Bessel functions of the first kind
|
| 6454 |
+
double cyl_bessel_j(double nu, double x);
|
| 6455 |
+
float cyl_bessel_jf(float nu, float x);
|
| 6456 |
+
long double cyl_bessel_jl(long double nu, long double x);
|
| 6457 |
+
|
| 6458 |
+
// [sf.cmath.cyl_bessel_k], irregular modified cylindrical Bessel functions
|
| 6459 |
+
double cyl_bessel_k(double nu, double x);
|
| 6460 |
+
float cyl_bessel_kf(float nu, float x);
|
| 6461 |
+
long double cyl_bessel_kl(long double nu, long double x);
|
| 6462 |
+
|
| 6463 |
+
// [sf.cmath.cyl_neumann], cylindrical Neumann functions;
|
| 6464 |
+
// cylindrical Bessel functions of the second kind
|
| 6465 |
+
double cyl_neumann(double nu, double x);
|
| 6466 |
+
float cyl_neumannf(float nu, float x);
|
| 6467 |
+
long double cyl_neumannl(long double nu, long double x);
|
| 6468 |
+
|
| 6469 |
+
// [sf.cmath.ellint_1], incomplete elliptic integral of the first kind
|
| 6470 |
+
double ellint_1(double k, double phi);
|
| 6471 |
+
float ellint_1f(float k, float phi);
|
| 6472 |
+
long double ellint_1l(long double k, long double phi);
|
| 6473 |
+
|
| 6474 |
+
// [sf.cmath.ellint_2], incomplete elliptic integral of the second kind
|
| 6475 |
+
double ellint_2(double k, double phi);
|
| 6476 |
+
float ellint_2f(float k, float phi);
|
| 6477 |
+
long double ellint_2l(long double k, long double phi);
|
| 6478 |
+
|
| 6479 |
+
// [sf.cmath.ellint_3], incomplete elliptic integral of the third kind
|
| 6480 |
+
double ellint_3(double k, double nu, double phi);
|
| 6481 |
+
float ellint_3f(float k, float nu, float phi);
|
| 6482 |
+
long double ellint_3l(long double k, long double nu, long double phi);
|
| 6483 |
+
|
| 6484 |
+
// [sf.cmath.expint], exponential integral
|
| 6485 |
+
double expint(double x);
|
| 6486 |
+
float expintf(float x);
|
| 6487 |
+
long double expintl(long double x);
|
| 6488 |
+
|
| 6489 |
+
// [sf.cmath.hermite], Hermite polynomials
|
| 6490 |
+
double hermite(unsigned n, double x);
|
| 6491 |
+
float hermitef(unsigned n, float x);
|
| 6492 |
+
long double hermitel(unsigned n, long double x);
|
| 6493 |
+
|
| 6494 |
+
// [sf.cmath.laguerre], Laguerre polynomials
|
| 6495 |
+
double laguerre(unsigned n, double x);
|
| 6496 |
+
float laguerref(unsigned n, float x);
|
| 6497 |
+
long double laguerrel(unsigned n, long double x);
|
| 6498 |
+
|
| 6499 |
+
// [sf.cmath.legendre], Legendre polynomials
|
| 6500 |
+
double legendre(unsigned l, double x);
|
| 6501 |
+
float legendref(unsigned l, float x);
|
| 6502 |
+
long double legendrel(unsigned l, long double x);
|
| 6503 |
+
|
| 6504 |
+
// [sf.cmath.riemann_zeta], Riemann zeta function
|
| 6505 |
+
double riemann_zeta(double x);
|
| 6506 |
+
float riemann_zetaf(float x);
|
| 6507 |
+
long double riemann_zetal(long double x);
|
| 6508 |
+
|
| 6509 |
+
// [sf.cmath.sph_bessel], spherical Bessel functions of the first kind
|
| 6510 |
+
double sph_bessel(unsigned n, double x);
|
| 6511 |
+
float sph_besself(unsigned n, float x);
|
| 6512 |
+
long double sph_bessell(unsigned n, long double x);
|
| 6513 |
+
|
| 6514 |
+
// [sf.cmath.sph_legendre], spherical associated Legendre functions
|
| 6515 |
+
double sph_legendre(unsigned l, unsigned m, double theta);
|
| 6516 |
+
float sph_legendref(unsigned l, unsigned m, float theta);
|
| 6517 |
+
long double sph_legendrel(unsigned l, unsigned m, long double theta);
|
| 6518 |
+
|
| 6519 |
+
// [sf.cmath.sph_neumann], spherical Neumann functions;
|
| 6520 |
+
// spherical Bessel functions of the second kind:
|
| 6521 |
+
double sph_neumann(unsigned n, double x);
|
| 6522 |
+
float sph_neumannf(unsigned n, float x);
|
| 6523 |
+
long double sph_neumannl(unsigned n, long double x);
|
| 6524 |
+
}
|
| 6525 |
+
```
|
| 6526 |
+
|
| 6527 |
+
The contents and meaning of the header `<cmath>` are the same as the C
|
| 6528 |
+
standard library header `<math.h>`, with the addition of a
|
| 6529 |
+
three-dimensional hypotenuse function ([[c.math.hypot3]]) and the
|
| 6530 |
+
mathematical special functions described in [[sf.cmath]].
|
| 6531 |
+
|
| 6532 |
+
[*Note 1*: Several functions have additional overloads in this
|
| 6533 |
+
International Standard, but they have the same behavior as in the C
|
| 6534 |
+
standard library ([[library.c]]). — *end note*]
|
| 6535 |
+
|
| 6536 |
+
For each set of overloaded functions within `<cmath>`, with the
|
| 6537 |
+
exception of `abs`, there shall be additional overloads sufficient to
|
| 6538 |
+
ensure:
|
| 6539 |
+
|
| 6540 |
+
1. If any argument of arithmetic type corresponding to a `double`
|
| 6541 |
+
parameter has type `long double`, then all arguments of arithmetic
|
| 6542 |
+
type ([[basic.fundamental]]) corresponding to `double` parameters
|
| 6543 |
+
are effectively cast to `long double`.
|
| 6544 |
+
2. Otherwise, if any argument of arithmetic type corresponding to a
|
| 6545 |
+
`double` parameter has type `double` or an integer type, then all
|
| 6546 |
+
arguments of arithmetic type corresponding to `double` parameters
|
| 6547 |
+
are effectively cast to `double`.
|
| 6548 |
+
3. Otherwise, all arguments of arithmetic type corresponding to
|
| 6549 |
+
`double` parameters have type `float`.
|
| 6550 |
+
|
| 6551 |
+
[*Note 2*: `abs` is exempted from these rules in order to stay
|
| 6552 |
+
compatible with C. — *end note*]
|
| 6553 |
+
|
| 6554 |
+
ISO C 7.12
|
| 6555 |
+
|
| 6556 |
+
### Absolute values <a id="c.math.abs">[[c.math.abs]]</a>
|
| 6557 |
+
|
| 6558 |
+
[*Note 1*: The headers `<cstdlib>` ([[cstdlib.syn]]) and `<cmath>` (
|
| 6559 |
+
[[cmath.syn]]) declare the functions described in this
|
| 6560 |
+
subclause. — *end note*]
|
| 6561 |
+
|
| 6562 |
+
``` cpp
|
| 6563 |
+
int abs(int j);
|
| 6564 |
+
long int abs(long int j);
|
| 6565 |
+
long long int abs(long long int j);
|
| 6566 |
+
float abs(float j);
|
| 6567 |
+
double abs(double j);
|
| 6568 |
+
long double abs(long double j);
|
| 6569 |
+
```
|
| 6570 |
+
|
| 6571 |
+
*Effects:* The `abs` functions have the semantics specified in the C
|
| 6572 |
+
standard library for the functions `abs`, `labs`, `llabs`, `fabsf`,
|
| 6573 |
+
`fabs`, and `fabsl`.
|
| 6574 |
+
|
| 6575 |
+
*Remarks:* If `abs()` is called with an argument of type `X` for which
|
| 6576 |
+
`is_unsigned_v<X>` is `true` and if `X` cannot be converted to `int` by
|
| 6577 |
+
integral promotion ([[conv.prom]]), the program is ill-formed.
|
| 6578 |
+
|
| 6579 |
+
[*Note 1*: Arguments that can be promoted to `int` are permitted for
|
| 6580 |
+
compatibility with C. — *end note*]
|
| 6581 |
+
|
| 6582 |
+
ISO C 7.12.7.2, 7.22.6.1
|
| 6583 |
+
|
| 6584 |
+
### Three-dimensional hypotenuse <a id="c.math.hypot3">[[c.math.hypot3]]</a>
|
| 6585 |
+
|
| 6586 |
+
``` cpp
|
| 6587 |
+
float hypot(float x, float y, float z);
|
| 6588 |
+
double hypot(double x, double y, double z);
|
| 6589 |
+
long double hypot(long double x, long double y, long double z);
|
| 6590 |
+
```
|
| 6591 |
+
|
| 6592 |
+
*Returns:* $\sqrt{x^2+y^2+z^2}$.
|
| 6593 |
+
|
| 6594 |
+
### Classification / comparison functions <a id="c.math.fpclass">[[c.math.fpclass]]</a>
|
| 6595 |
+
|
| 6596 |
+
The classification / comparison functions behave the same as the C
|
| 6597 |
+
macros with the corresponding names defined in the C standard library.
|
| 6598 |
+
Each function is overloaded for the three floating-point types.
|
| 6599 |
+
|
| 6600 |
+
ISO C 7.12.3, 7.12.4
|
| 6601 |
+
|
| 6602 |
+
### Mathematical special functions <a id="sf.cmath">[[sf.cmath]]</a>
|
| 6603 |
+
|
| 6604 |
+
If any argument value to any of the functions specified in this
|
| 6605 |
+
subclause is a NaN (Not a Number), the function shall return a NaN but
|
| 6606 |
+
it shall not report a domain error. Otherwise, the function shall report
|
| 6607 |
+
a domain error for just those argument values for which:
|
| 6608 |
+
|
| 6609 |
+
- the function description’s *Returns:* clause explicitly specifies a
|
| 6610 |
+
domain and those argument values fall outside the specified domain, or
|
| 6611 |
+
- the corresponding mathematical function value has a nonzero imaginary
|
| 6612 |
+
component, or
|
| 6613 |
+
- the corresponding mathematical function is not mathematically
|
| 6614 |
+
defined.[^18]
|
| 6615 |
+
|
| 6616 |
+
Unless otherwise specified, each function is defined for all finite
|
| 6617 |
+
values, for negative infinity, and for positive infinity.
|
| 6618 |
+
|
| 6619 |
+
#### Associated Laguerre polynomials <a id="sf.cmath.assoc_laguerre">[[sf.cmath.assoc_laguerre]]</a>
|
| 6620 |
+
|
| 6621 |
+
``` cpp
|
| 6622 |
+
double assoc_laguerre(unsigned n, unsigned m, double x);
|
| 6623 |
+
float assoc_laguerref(unsigned n, unsigned m, float x);
|
| 6624 |
+
long double assoc_laguerrel(unsigned n, unsigned m, long double x);
|
| 6625 |
+
```
|
| 6626 |
+
|
| 6627 |
+
*Effects:* These functions compute the associated Laguerre polynomials
|
| 6628 |
+
of their respective arguments `n`, `m`, and `x`.
|
| 6629 |
+
|
| 6630 |
+
*Returns:* $$%
|
| 6631 |
+
\mathsf{L}_n^m(x) =
|
| 6632 |
+
(-1)^m \frac{\mathsf{d} ^ m}
|
| 6633 |
+
{\mathsf{d}x ^ m} \, \mathsf{L}_{n+m}(x),
|
| 6634 |
+
\quad \mbox{for $x \ge 0$}$$ where n is `n`, m is `m`, and x is
|
| 6635 |
+
`x`.
|
| 6636 |
+
|
| 6637 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6638 |
+
*implementation-defined* if `n >= 128` or if `m >= 128`.
|
| 6639 |
+
|
| 6640 |
+
#### Associated Legendre functions <a id="sf.cmath.assoc_legendre">[[sf.cmath.assoc_legendre]]</a>
|
| 6641 |
+
|
| 6642 |
+
``` cpp
|
| 6643 |
+
double assoc_legendre(unsigned l, unsigned m, double x);
|
| 6644 |
+
float assoc_legendref(unsigned l, unsigned m, float x);
|
| 6645 |
+
long double assoc_legendrel(unsigned l, unsigned m, long double x);
|
| 6646 |
+
```
|
| 6647 |
+
|
| 6648 |
+
*Effects:* These functions compute the associated Legendre functions of
|
| 6649 |
+
their respective arguments `l`, `m`, and `x`.
|
| 6650 |
+
|
| 6651 |
+
*Returns:* $$%
|
| 6652 |
+
\mathsf{P}_\ell^m(x) =
|
| 6653 |
+
(1 - x^2) ^ {m/2}
|
| 6654 |
+
\:
|
| 6655 |
+
\frac{ \mathsf{d} ^ m}
|
| 6656 |
+
{ \mathsf{d}x ^ m} \, \mathsf{P}_\ell(x),
|
| 6657 |
+
\quad \mbox{for $|x| \le 1$}$$ where l is `l`, m is `m`, and x is
|
| 6658 |
+
`x`.
|
| 6659 |
+
|
| 6660 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6661 |
+
*implementation-defined* if `l >= 128`.
|
| 6662 |
+
|
| 6663 |
+
#### Beta function <a id="sf.cmath.beta">[[sf.cmath.beta]]</a>
|
| 6664 |
+
|
| 6665 |
+
``` cpp
|
| 6666 |
+
double beta(double x, double y);
|
| 6667 |
+
float betaf(float x, float y);
|
| 6668 |
+
long double betal(long double x, long double y);
|
| 6669 |
+
```
|
| 6670 |
+
|
| 6671 |
+
*Effects:* These functions compute the beta function of their respective
|
| 6672 |
+
arguments `x` and `y`.
|
| 6673 |
+
|
| 6674 |
+
*Returns:* $$%
|
| 6675 |
+
\mathsf{B}(x, y) =
|
| 6676 |
+
\frac{ \Gamma(x) \, \Gamma(y) }
|
| 6677 |
+
{ \Gamma(x+y) },
|
| 6678 |
+
\quad \mbox{for $x > 0$,\, $y > 0$}$$ where x is `x` and y is
|
| 6679 |
+
`y`.
|
| 6680 |
+
|
| 6681 |
+
#### Complete elliptic integral of the first kind <a id="sf.cmath.comp_ellint_1">[[sf.cmath.comp_ellint_1]]</a>
|
| 6682 |
+
|
| 6683 |
+
``` cpp
|
| 6684 |
+
double comp_ellint_1(double k);
|
| 6685 |
+
float comp_ellint_1f(float k);
|
| 6686 |
+
long double comp_ellint_1l(long double k);
|
| 6687 |
+
```
|
| 6688 |
+
|
| 6689 |
+
*Effects:* These functions compute the complete elliptic integral of the
|
| 6690 |
+
first kind of their respective arguments `k`.
|
| 6691 |
+
|
| 6692 |
+
*Returns:* $$%
|
| 6693 |
+
\mathsf{K}(k) =
|
| 6694 |
+
\mathsf{F}(k, \pi / 2),
|
| 6695 |
+
\quad \mbox{for $|k| \le 1$}$$ where k is `k`.
|
| 6696 |
+
|
| 6697 |
+
See also [[sf.cmath.ellint_1]].
|
| 6698 |
+
|
| 6699 |
+
#### Complete elliptic integral of the second kind <a id="sf.cmath.comp_ellint_2">[[sf.cmath.comp_ellint_2]]</a>
|
| 6700 |
+
|
| 6701 |
+
``` cpp
|
| 6702 |
+
double comp_ellint_2(double k);
|
| 6703 |
+
float comp_ellint_2f(float k);
|
| 6704 |
+
long double comp_ellint_2l(long double k);
|
| 6705 |
+
```
|
| 6706 |
+
|
| 6707 |
+
*Effects:* These functions compute the complete elliptic integral of the
|
| 6708 |
+
second kind of their respective arguments `k`.
|
| 6709 |
+
|
| 6710 |
+
*Returns:* $$%
|
| 6711 |
+
\mathsf{E}(k) =
|
| 6712 |
+
\mathsf{E}(k, \pi / 2),
|
| 6713 |
+
\quad \mbox{for $|k| \le 1$}$$ where k is `k`.
|
| 6714 |
+
|
| 6715 |
+
See also [[sf.cmath.ellint_2]].
|
| 6716 |
+
|
| 6717 |
+
#### Complete elliptic integral of the third kind <a id="sf.cmath.comp_ellint_3">[[sf.cmath.comp_ellint_3]]</a>
|
| 6718 |
+
|
| 6719 |
+
``` cpp
|
| 6720 |
+
double comp_ellint_3(double k, double nu);
|
| 6721 |
+
float comp_ellint_3f(float k, float nu);
|
| 6722 |
+
long double comp_ellint_3l(long double k, long double nu);
|
| 6723 |
+
```
|
| 6724 |
+
|
| 6725 |
+
*Effects:* These functions compute the complete elliptic integral of the
|
| 6726 |
+
third kind of their respective arguments `k` and `nu`.
|
| 6727 |
+
|
| 6728 |
+
*Returns:* $$%
|
| 6729 |
+
\mathsf{\Pi}(\nu, k) = \mathsf{\Pi}(\nu, k, \pi / 2),
|
| 6730 |
+
\quad \mbox{for $|k| \le 1$}$$ where k is `k` and $\nu$ is `nu`.
|
| 6731 |
+
|
| 6732 |
+
See also [[sf.cmath.ellint_3]].
|
| 6733 |
+
|
| 6734 |
+
#### Regular modified cylindrical Bessel functions <a id="sf.cmath.cyl_bessel_i">[[sf.cmath.cyl_bessel_i]]</a>
|
| 6735 |
+
|
| 6736 |
+
``` cpp
|
| 6737 |
+
double cyl_bessel_i(double nu, double x);
|
| 6738 |
+
float cyl_bessel_if(float nu, float x);
|
| 6739 |
+
long double cyl_bessel_il(long double nu, long double x);
|
| 6740 |
+
```
|
| 6741 |
+
|
| 6742 |
+
*Effects:* These functions compute the regular modified cylindrical
|
| 6743 |
+
Bessel functions of their respective arguments `nu` and `x`.
|
| 6744 |
+
|
| 6745 |
+
*Returns:* $$%
|
| 6746 |
+
\mathsf{I}_\nu(x) =
|
| 6747 |
+
i^{-\nu} \mathsf{J}_\nu(ix)
|
| 6748 |
+
=
|
| 6749 |
+
\sum_{k=0}^\infty \frac{(x/2)^{\nu+2k}}
|
| 6750 |
+
{k! \: \Gamma(\nu+k+1)},
|
| 6751 |
+
\quad \mbox{for $x \ge 0$}$$ where $\nu$ is `nu` and x is `x`.
|
| 6752 |
+
|
| 6753 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6754 |
+
*implementation-defined* if `nu >= 128`.
|
| 6755 |
+
|
| 6756 |
+
See also [[sf.cmath.cyl_bessel_j]].
|
| 6757 |
+
|
| 6758 |
+
#### Cylindrical Bessel functions of the first kind <a id="sf.cmath.cyl_bessel_j">[[sf.cmath.cyl_bessel_j]]</a>
|
| 6759 |
+
|
| 6760 |
+
``` cpp
|
| 6761 |
+
double cyl_bessel_j(double nu, double x);
|
| 6762 |
+
float cyl_bessel_jf(float nu, float x);
|
| 6763 |
+
long double cyl_bessel_jl(long double nu, long double x);
|
| 6764 |
+
```
|
| 6765 |
+
|
| 6766 |
+
*Effects:* These functions compute the cylindrical Bessel functions of
|
| 6767 |
+
the first kind of their respective arguments `nu` and `x`.
|
| 6768 |
+
|
| 6769 |
+
*Returns:* $$%
|
| 6770 |
+
\mathsf{J}_\nu(x) =
|
| 6771 |
+
\sum_{k=0}^\infty \frac{(-1)^k (x/2)^{\nu+2k}}
|
| 6772 |
+
{k! \: \Gamma(\nu+k+1)},
|
| 6773 |
+
\quad \mbox{for $x \ge 0$}$$ where $\nu$ is `nu` and x is `x`.
|
| 6774 |
+
|
| 6775 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6776 |
+
*implementation-defined* if `nu >= 128`.
|
| 6777 |
+
|
| 6778 |
+
#### Irregular modified cylindrical Bessel functions <a id="sf.cmath.cyl_bessel_k">[[sf.cmath.cyl_bessel_k]]</a>
|
| 6779 |
+
|
| 6780 |
+
``` cpp
|
| 6781 |
+
double cyl_bessel_k(double nu, double x);
|
| 6782 |
+
float cyl_bessel_kf(float nu, float x);
|
| 6783 |
+
long double cyl_bessel_kl(long double nu, long double x);
|
| 6784 |
+
```
|
| 6785 |
+
|
| 6786 |
+
*Effects:* These functions compute the irregular modified cylindrical
|
| 6787 |
+
Bessel functions of their respective arguments `nu` and `x`.
|
| 6788 |
+
|
| 6789 |
+
*Returns:* $$%
|
| 6790 |
+
\mathsf{K}_\nu(x) =
|
| 6791 |
+
(\pi/2)i^{\nu+1} ( \mathsf{J}_\nu(ix)
|
| 6792 |
+
+ i \mathsf{N}_\nu(ix)
|
| 6793 |
+
)
|
| 6794 |
+
=
|
| 6795 |
+
\left\{
|
| 6796 |
+
\begin{array}{cl}
|
| 6797 |
+
\displaystyle
|
| 6798 |
+
\frac{\pi}{2}
|
| 6799 |
+
\frac{\mathsf{I}_{-\nu}(x) - \mathsf{I}_{\nu}(x)}
|
| 6800 |
+
{\sin \nu\pi },
|
| 6801 |
+
& \mbox{for $x \ge 0$ and non-integral $\nu$}
|
| 6802 |
+
\\
|
| 6803 |
+
\\
|
| 6804 |
+
\displaystyle
|
| 6805 |
+
\frac{\pi}{2}
|
| 6806 |
+
\lim_{\mu \rightarrow \nu} \frac{\mathsf{I}_{-\mu}(x) - \mathsf{I}_{\mu}(x)}
|
| 6807 |
+
{\sin \mu\pi },
|
| 6808 |
+
& \mbox{for $x \ge 0$ and integral $\nu$}
|
| 6809 |
+
\end{array}
|
| 6810 |
+
\right.$$ where $\nu$ is `nu` and x is `x`.
|
| 6811 |
+
|
| 6812 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6813 |
+
*implementation-defined* if `nu >= 128`.
|
| 6814 |
+
|
| 6815 |
+
See also [[sf.cmath.cyl_bessel_i]], [[sf.cmath.cyl_bessel_j]],
|
| 6816 |
+
[[sf.cmath.cyl_neumann]].
|
| 6817 |
+
|
| 6818 |
+
#### Cylindrical Neumann functions <a id="sf.cmath.cyl_neumann">[[sf.cmath.cyl_neumann]]</a>
|
| 6819 |
+
|
| 6820 |
+
``` cpp
|
| 6821 |
+
double cyl_neumann(double nu, double x);
|
| 6822 |
+
float cyl_neumannf(float nu, float x);
|
| 6823 |
+
long double cyl_neumannl(long double nu, long double x);
|
| 6824 |
+
```
|
| 6825 |
+
|
| 6826 |
+
*Effects:* These functions compute the cylindrical Neumann functions,
|
| 6827 |
+
also known as the cylindrical Bessel functions of the second kind, of
|
| 6828 |
+
their respective arguments `nu` and `x`.
|
| 6829 |
+
|
| 6830 |
+
*Returns:* $$%
|
| 6831 |
+
\mathsf{N}_\nu(x) =
|
| 6832 |
+
\left\{
|
| 6833 |
+
\begin{array}{cl}
|
| 6834 |
+
\displaystyle
|
| 6835 |
+
\frac{\mathsf{J}_\nu(x) \cos \nu\pi - \mathsf{J}_{-\nu}(x)}
|
| 6836 |
+
{\sin \nu\pi },
|
| 6837 |
+
& \mbox{for $x \ge 0$ and non-integral $\nu$}
|
| 6838 |
+
\\
|
| 6839 |
+
\\
|
| 6840 |
+
\displaystyle
|
| 6841 |
+
\lim_{\mu \rightarrow \nu} \frac{\mathsf{J}_\mu(x) \cos \mu\pi - \mathsf{J}_{-\mu}(x)}
|
| 6842 |
+
{\sin \mu\pi },
|
| 6843 |
+
& \mbox{for $x \ge 0$ and integral $\nu$}
|
| 6844 |
+
\end{array}
|
| 6845 |
+
\right.$$ where $\nu$ is `nu` and x is `x`.
|
| 6846 |
+
|
| 6847 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6848 |
+
*implementation-defined* if `nu >= 128`.
|
| 6849 |
+
|
| 6850 |
+
See also [[sf.cmath.cyl_bessel_j]].
|
| 6851 |
+
|
| 6852 |
+
#### Incomplete elliptic integral of the first kind <a id="sf.cmath.ellint_1">[[sf.cmath.ellint_1]]</a>
|
| 6853 |
+
|
| 6854 |
+
``` cpp
|
| 6855 |
+
double ellint_1(double k, double phi);
|
| 6856 |
+
float ellint_1f(float k, float phi);
|
| 6857 |
+
long double ellint_1l(long double k, long double phi);
|
| 6858 |
+
```
|
| 6859 |
+
|
| 6860 |
+
*Effects:* These functions compute the incomplete elliptic integral of
|
| 6861 |
+
the first kind of their respective arguments `k` and `phi` (`phi`
|
| 6862 |
+
measured in radians).
|
| 6863 |
+
|
| 6864 |
+
*Returns:* $$%
|
| 6865 |
+
\mathsf{F}(k, \phi) =
|
| 6866 |
+
\int_0^\phi \! \frac{\mathsf{d}\theta}
|
| 6867 |
+
{\sqrt{1 - k^2 \sin^2 \theta}},
|
| 6868 |
+
\quad \mbox{for $|k| \le 1$}$$ where k is `k` and φ is `phi`.
|
| 6869 |
+
|
| 6870 |
+
#### Incomplete elliptic integral of the second kind <a id="sf.cmath.ellint_2">[[sf.cmath.ellint_2]]</a>
|
| 6871 |
+
|
| 6872 |
+
``` cpp
|
| 6873 |
+
double ellint_2(double k, double phi);
|
| 6874 |
+
float ellint_2f(float k, float phi);
|
| 6875 |
+
long double ellint_2l(long double k, long double phi);
|
| 6876 |
+
```
|
| 6877 |
+
|
| 6878 |
+
*Effects:* These functions compute the incomplete elliptic integral of
|
| 6879 |
+
the second kind of their respective arguments `k` and `phi` (`phi`
|
| 6880 |
+
measured in radians).
|
| 6881 |
+
|
| 6882 |
+
*Returns:* $$%
|
| 6883 |
+
\mathsf{E}(k, \phi) =
|
| 6884 |
+
\int_0^\phi \! \sqrt{1 - k^2 \sin^2 \theta} \, \mathsf{d}\theta,
|
| 6885 |
+
\quad \mbox{for $|k| \le 1$}$$ where k is `k` and φ is `phi`.
|
| 6886 |
+
|
| 6887 |
+
#### Incomplete elliptic integral of the third kind <a id="sf.cmath.ellint_3">[[sf.cmath.ellint_3]]</a>
|
| 6888 |
+
|
| 6889 |
+
``` cpp
|
| 6890 |
+
double ellint_3(double k, double nu, double phi);
|
| 6891 |
+
float ellint_3f(float k, float nu, float phi);
|
| 6892 |
+
long double ellint_3l(long double k, long double nu, long double phi);
|
| 6893 |
+
```
|
| 6894 |
+
|
| 6895 |
+
*Effects:* These functions compute the incomplete elliptic integral of
|
| 6896 |
+
the third kind of their respective arguments `k`, `nu`, and `phi` (`phi`
|
| 6897 |
+
measured in radians).
|
| 6898 |
+
|
| 6899 |
+
*Returns:* $$%
|
| 6900 |
+
\mathsf{\Pi}(\nu, k, \phi) =
|
| 6901 |
+
\int_0^\phi \! \frac{ \mathsf{d}\theta }
|
| 6902 |
+
{ (1 - \nu \, \sin^2 \theta) \sqrt{1 - k^2 \sin^2 \theta} },
|
| 6903 |
+
\quad \mbox{for $|k| \le 1$}$$ where $\nu$ is `nu`, k is `k`, and
|
| 6904 |
+
φ is `phi`.
|
| 6905 |
+
|
| 6906 |
+
#### Exponential integral <a id="sf.cmath.expint">[[sf.cmath.expint]]</a>
|
| 6907 |
+
|
| 6908 |
+
``` cpp
|
| 6909 |
+
double expint(double x);
|
| 6910 |
+
float expintf(float x);
|
| 6911 |
+
long double expintl(long double x);
|
| 6912 |
+
```
|
| 6913 |
+
|
| 6914 |
+
*Effects:* These functions compute the exponential integral of their
|
| 6915 |
+
respective arguments `x`.
|
| 6916 |
+
|
| 6917 |
+
*Returns:* $$%
|
| 6918 |
+
\mathsf{Ei}(x) =
|
| 6919 |
+
- \int_{-x}^\infty \frac{e^{-t}}
|
| 6920 |
+
{t } \, \mathsf{d}t
|
| 6921 |
+
\;$$ where x is `x`.
|
| 6922 |
+
|
| 6923 |
+
#### Hermite polynomials <a id="sf.cmath.hermite">[[sf.cmath.hermite]]</a>
|
| 6924 |
+
|
| 6925 |
+
``` cpp
|
| 6926 |
+
double hermite(unsigned n, double x);
|
| 6927 |
+
float hermitef(unsigned n, float x);
|
| 6928 |
+
long double hermitel(unsigned n, long double x);
|
| 6929 |
+
```
|
| 6930 |
+
|
| 6931 |
+
*Effects:* These functions compute the Hermite polynomials of their
|
| 6932 |
+
respective arguments `n` and `x`.
|
| 6933 |
+
|
| 6934 |
+
*Returns:* $$%
|
| 6935 |
+
\mathsf{H}_n(x) =
|
| 6936 |
+
(-1)^n e^{x^2} \frac{ \mathsf{d} ^n}
|
| 6937 |
+
{ \mathsf{d}x^n} \, e^{-x^2}
|
| 6938 |
+
\;$$ where n is `n` and x is `x`.
|
| 6939 |
+
|
| 6940 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6941 |
+
*implementation-defined* if `n >= 128`.
|
| 6942 |
+
|
| 6943 |
+
#### Laguerre polynomials <a id="sf.cmath.laguerre">[[sf.cmath.laguerre]]</a>
|
| 6944 |
+
|
| 6945 |
+
``` cpp
|
| 6946 |
+
double laguerre(unsigned n, double x);
|
| 6947 |
+
float laguerref(unsigned n, float x);
|
| 6948 |
+
long double laguerrel(unsigned n, long double x);
|
| 6949 |
+
```
|
| 6950 |
+
|
| 6951 |
+
*Effects:* These functions compute the Laguerre polynomials of their
|
| 6952 |
+
respective arguments `n` and `x`.
|
| 6953 |
+
|
| 6954 |
+
*Returns:* $$%
|
| 6955 |
+
\mathsf{L}_n(x) =
|
| 6956 |
+
\frac{e^x}{n!} \frac{ \mathsf{d} ^ n}
|
| 6957 |
+
{ \mathsf{d}x ^ n} \, (x^n e^{-x}),
|
| 6958 |
+
\quad \mbox{for $x \ge 0$}$$ where n is `n` and x is `x`.
|
| 6959 |
+
|
| 6960 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6961 |
+
*implementation-defined* if `n >= 128`.
|
| 6962 |
+
|
| 6963 |
+
#### Legendre polynomials <a id="sf.cmath.legendre">[[sf.cmath.legendre]]</a>
|
| 6964 |
+
|
| 6965 |
+
``` cpp
|
| 6966 |
+
double legendre(unsigned l, double x);
|
| 6967 |
+
float legendref(unsigned l, float x);
|
| 6968 |
+
long double legendrel(unsigned l, long double x);
|
| 6969 |
+
```
|
| 6970 |
+
|
| 6971 |
+
*Effects:* These functions compute the Legendre polynomials of their
|
| 6972 |
+
respective arguments `l` and `x`.
|
| 6973 |
+
|
| 6974 |
+
*Returns:* $$%
|
| 6975 |
+
\mathsf{P}_\ell(x) =
|
| 6976 |
+
\frac{1}
|
| 6977 |
+
{2^\ell \, \ell!}
|
| 6978 |
+
\frac{ \mathsf{d} ^ \ell}
|
| 6979 |
+
{ \mathsf{d}x ^ \ell} \, (x^2 - 1) ^ \ell,
|
| 6980 |
+
\quad \mbox{for $|x| \le 1$}$$ where l is `l` and x is `x`.
|
| 6981 |
+
|
| 6982 |
+
*Remarks:* The effect of calling each of these functions is
|
| 6983 |
+
*implementation-defined* if `l >= 128`.
|
| 6984 |
+
|
| 6985 |
+
#### Riemann zeta function <a id="sf.cmath.riemann_zeta">[[sf.cmath.riemann_zeta]]</a>
|
| 6986 |
+
|
| 6987 |
+
``` cpp
|
| 6988 |
+
double riemann_zeta(double x);
|
| 6989 |
+
float riemann_zetaf(float x);
|
| 6990 |
+
long double riemann_zetal(long double x);
|
| 6991 |
+
```
|
| 6992 |
+
|
| 6993 |
+
*Effects:* These functions compute the Riemann zeta function of their
|
| 6994 |
+
respective arguments `x`.
|
| 6995 |
+
|
| 6996 |
+
*Returns:* $$%
|
| 6997 |
+
\mathsf{\zeta}(x) =
|
| 6998 |
+
\left\{
|
| 6999 |
+
\begin{array}{cl}
|
| 7000 |
+
\displaystyle
|
| 7001 |
+
\sum_{k=1}^\infty k^{-x},
|
| 7002 |
+
& \mbox{for $x > 1$}
|
| 7003 |
+
\\
|
| 7004 |
+
\\
|
| 7005 |
+
\displaystyle
|
| 7006 |
+
\frac{1}
|
| 7007 |
+
{1 - 2^{1-x}}
|
| 7008 |
+
\sum_{k=1}^\infty (-1)^{k-1} k^{-x},
|
| 7009 |
+
& \mbox{for $0 \le x \le 1$}
|
| 7010 |
+
\\
|
| 7011 |
+
\\
|
| 7012 |
+
\displaystyle
|
| 7013 |
+
2^x \pi^{x-1} \sin(\frac{\pi x}{2}) \, \Gamma(1-x) \, \zeta(1-x),
|
| 7014 |
+
& \mbox{for $x < 0$}
|
| 7015 |
+
\end{array}
|
| 7016 |
+
\right.
|
| 7017 |
+
\;$$ where x is `x`.
|
| 7018 |
+
|
| 7019 |
+
#### Spherical Bessel functions of the first kind <a id="sf.cmath.sph_bessel">[[sf.cmath.sph_bessel]]</a>
|
| 7020 |
+
|
| 7021 |
+
``` cpp
|
| 7022 |
+
double sph_bessel(unsigned n, double x);
|
| 7023 |
+
float sph_besself(unsigned n, float x);
|
| 7024 |
+
long double sph_bessell(unsigned n, long double x);
|
| 7025 |
+
```
|
| 7026 |
+
|
| 7027 |
+
*Effects:* These functions compute the spherical Bessel functions of the
|
| 7028 |
+
first kind of their respective arguments `n` and `x`.
|
| 7029 |
+
|
| 7030 |
+
*Returns:* $$%
|
| 7031 |
+
\mathsf{j}_n(x) =
|
| 7032 |
+
(\pi/2x)^{1\!/\!2} \mathsf{J}_{n + 1\!/\!2}(x),
|
| 7033 |
+
\quad \mbox{for $x \ge 0$}$$ where n is `n` and x is `x`.
|
| 7034 |
+
|
| 7035 |
+
*Remarks:* The effect of calling each of these functions is
|
| 7036 |
+
*implementation-defined* if `n >= 128`.
|
| 7037 |
+
|
| 7038 |
+
See also [[sf.cmath.cyl_bessel_j]].
|
| 7039 |
+
|
| 7040 |
+
#### Spherical associated Legendre functions <a id="sf.cmath.sph_legendre">[[sf.cmath.sph_legendre]]</a>
|
| 7041 |
+
|
| 7042 |
+
``` cpp
|
| 7043 |
+
double sph_legendre(unsigned l, unsigned m, double theta);
|
| 7044 |
+
float sph_legendref(unsigned l, unsigned m, float theta);
|
| 7045 |
+
long double sph_legendrel(unsigned l, unsigned m, long double theta);
|
| 7046 |
+
```
|
| 7047 |
+
|
| 7048 |
+
*Effects:* These functions compute the spherical associated Legendre
|
| 7049 |
+
functions of their respective arguments `l`, `m`, and `theta` (`theta`
|
| 7050 |
+
measured in radians).
|
| 7051 |
+
|
| 7052 |
+
*Returns:* $$%
|
| 7053 |
+
\mathsf{Y}_\ell^m(\theta, 0)
|
| 7054 |
+
\;$$ where $$%
|
| 7055 |
+
\mathsf{Y}_\ell^m(\theta, \phi) =
|
| 7056 |
+
(-1)^m \left[ \frac{(2 \ell + 1)}
|
| 7057 |
+
{4 \pi}
|
| 7058 |
+
\frac{(\ell - m)!}
|
| 7059 |
+
{(\ell + m)!}
|
| 7060 |
+
\right]^{1/2}
|
| 7061 |
+
\mathsf{P}_\ell^m
|
| 7062 |
+
( \cos\theta ) e ^ {i m \phi},
|
| 7063 |
+
\quad \mbox{for $|m| \le \ell$}$$ and l is `l`, m is `m`, and θ
|
| 7064 |
+
is `theta`.
|
| 7065 |
+
|
| 7066 |
+
*Remarks:* The effect of calling each of these functions is
|
| 7067 |
+
*implementation-defined* if `l >= 128`.
|
| 7068 |
+
|
| 7069 |
+
See also [[sf.cmath.assoc_legendre]].
|
| 7070 |
+
|
| 7071 |
+
#### Spherical Neumann functions <a id="sf.cmath.sph_neumann">[[sf.cmath.sph_neumann]]</a>
|
| 7072 |
+
|
| 7073 |
+
``` cpp
|
| 7074 |
+
double sph_neumann(unsigned n, double x);
|
| 7075 |
+
float sph_neumannf(unsigned n, float x);
|
| 7076 |
+
long double sph_neumannl(unsigned n, long double x);
|
| 7077 |
+
```
|
| 7078 |
+
|
| 7079 |
+
*Effects:* These functions compute the spherical Neumann functions, also
|
| 7080 |
+
known as the spherical Bessel functions of the second kind, of their
|
| 7081 |
+
respective arguments `n` and `x`.
|
| 7082 |
+
|
| 7083 |
+
*Returns:* $$%
|
| 7084 |
+
\mathsf{n}_n(x) =
|
| 7085 |
+
(\pi/2x)^{1\!/\!2} \mathsf{N}_{n + 1\!/\!2}(x),
|
| 7086 |
+
\quad \mbox{for $x \ge 0$}$$ where n is `n` and x is `x`.
|
| 7087 |
+
|
| 7088 |
+
*Remarks:* The effect of calling each of these functions is
|
| 7089 |
+
*implementation-defined* if `n >= 128`.
|
| 7090 |
+
|
| 7091 |
+
See also [[sf.cmath.cyl_neumann]].
|
| 7092 |
|
| 7093 |
<!-- Link reference definitions -->
|
| 7094 |
[accumulate]: #accumulate
|
| 7095 |
[adjacent.difference]: #adjacent.difference
|
| 7096 |
[algorithms]: algorithms.md#algorithms
|
| 7097 |
[bad.alloc]: language.md#bad.alloc
|
| 7098 |
[basic.fundamental]: basic.md#basic.fundamental
|
| 7099 |
[basic.stc.thread]: basic.md#basic.stc.thread
|
| 7100 |
[basic.types]: basic.md#basic.types
|
| 7101 |
[c.math]: #c.math
|
| 7102 |
+
[c.math.abs]: #c.math.abs
|
| 7103 |
+
[c.math.fpclass]: #c.math.fpclass
|
| 7104 |
+
[c.math.hypot3]: #c.math.hypot3
|
| 7105 |
+
[c.math.rand]: #c.math.rand
|
| 7106 |
[cfenv]: #cfenv
|
| 7107 |
[cfenv.syn]: #cfenv.syn
|
| 7108 |
[class.gslice]: #class.gslice
|
| 7109 |
[class.gslice.overview]: #class.gslice.overview
|
| 7110 |
[class.slice]: #class.slice
|
| 7111 |
[class.slice.overview]: #class.slice.overview
|
| 7112 |
+
[cmath.syn]: #cmath.syn
|
| 7113 |
[cmplx.over]: #cmplx.over
|
| 7114 |
[complex]: #complex
|
| 7115 |
[complex.literals]: #complex.literals
|
| 7116 |
[complex.member.ops]: #complex.member.ops
|
| 7117 |
[complex.members]: #complex.members
|
|
|
|
| 7120 |
[complex.special]: #complex.special
|
| 7121 |
[complex.syn]: #complex.syn
|
| 7122 |
[complex.transcendentals]: #complex.transcendentals
|
| 7123 |
[complex.value.ops]: #complex.value.ops
|
| 7124 |
[cons.slice]: #cons.slice
|
| 7125 |
+
[conv.prom]: conv.md#conv.prom
|
| 7126 |
+
[cpp.pragma]: cpp.md#cpp.pragma
|
| 7127 |
+
[cstdlib.syn]: language.md#cstdlib.syn
|
| 7128 |
+
[dcl.array]: dcl.md#dcl.array
|
| 7129 |
[dcl.init]: dcl.md#dcl.init
|
| 7130 |
+
[exclusive.scan]: #exclusive.scan
|
| 7131 |
[function.objects]: utilities.md#function.objects
|
| 7132 |
[gslice.access]: #gslice.access
|
| 7133 |
[gslice.array.assign]: #gslice.array.assign
|
| 7134 |
[gslice.array.comp.assign]: #gslice.array.comp.assign
|
| 7135 |
[gslice.array.fill]: #gslice.array.fill
|
| 7136 |
[gslice.cons]: #gslice.cons
|
| 7137 |
+
[implimits]: limits.md#implimits
|
| 7138 |
+
[inclusive.scan]: #inclusive.scan
|
| 7139 |
[indirect.array.assign]: #indirect.array.assign
|
| 7140 |
[indirect.array.comp.assign]: #indirect.array.comp.assign
|
| 7141 |
[indirect.array.fill]: #indirect.array.fill
|
| 7142 |
[inner.product]: #inner.product
|
| 7143 |
+
[input.iterators]: iterators.md#input.iterators
|
| 7144 |
[input.output]: input.md#input.output
|
| 7145 |
[iostate.flags]: input.md#iostate.flags
|
| 7146 |
[istream.formatted]: input.md#istream.formatted
|
| 7147 |
+
[iterator.requirements.general]: iterators.md#iterator.requirements.general
|
| 7148 |
+
[library.c]: library.md#library.c
|
| 7149 |
[mask.array.assign]: #mask.array.assign
|
| 7150 |
[mask.array.comp.assign]: #mask.array.comp.assign
|
| 7151 |
[mask.array.fill]: #mask.array.fill
|
|
|
|
| 7152 |
[numarray]: #numarray
|
| 7153 |
[numeric.iota]: #numeric.iota
|
| 7154 |
[numeric.ops]: #numeric.ops
|
| 7155 |
+
[numeric.ops.gcd]: #numeric.ops.gcd
|
| 7156 |
+
[numeric.ops.lcm]: #numeric.ops.lcm
|
| 7157 |
[numeric.ops.overview]: #numeric.ops.overview
|
| 7158 |
[numeric.requirements]: #numeric.requirements
|
| 7159 |
[numerics]: #numerics
|
| 7160 |
+
[numerics.defns]: #numerics.defns
|
| 7161 |
[numerics.general]: #numerics.general
|
| 7162 |
+
[output.iterators]: iterators.md#output.iterators
|
| 7163 |
[partial.sum]: #partial.sum
|
| 7164 |
[rand]: #rand
|
| 7165 |
[rand.adapt]: #rand.adapt
|
| 7166 |
[rand.adapt.disc]: #rand.adapt.disc
|
| 7167 |
[rand.adapt.general]: #rand.adapt.general
|
|
|
|
| 7210 |
[rand.synopsis]: #rand.synopsis
|
| 7211 |
[rand.util]: #rand.util
|
| 7212 |
[rand.util.canonical]: #rand.util.canonical
|
| 7213 |
[rand.util.seedseq]: #rand.util.seedseq
|
| 7214 |
[random.access.iterators]: iterators.md#random.access.iterators
|
| 7215 |
+
[reduce]: #reduce
|
| 7216 |
[res.on.data.races]: library.md#res.on.data.races
|
| 7217 |
+
[sf.cmath]: #sf.cmath
|
| 7218 |
+
[sf.cmath.assoc_laguerre]: #sf.cmath.assoc_laguerre
|
| 7219 |
+
[sf.cmath.assoc_legendre]: #sf.cmath.assoc_legendre
|
| 7220 |
+
[sf.cmath.beta]: #sf.cmath.beta
|
| 7221 |
+
[sf.cmath.comp_ellint_1]: #sf.cmath.comp_ellint_1
|
| 7222 |
+
[sf.cmath.comp_ellint_2]: #sf.cmath.comp_ellint_2
|
| 7223 |
+
[sf.cmath.comp_ellint_3]: #sf.cmath.comp_ellint_3
|
| 7224 |
+
[sf.cmath.cyl_bessel_i]: #sf.cmath.cyl_bessel_i
|
| 7225 |
+
[sf.cmath.cyl_bessel_j]: #sf.cmath.cyl_bessel_j
|
| 7226 |
+
[sf.cmath.cyl_bessel_k]: #sf.cmath.cyl_bessel_k
|
| 7227 |
+
[sf.cmath.cyl_neumann]: #sf.cmath.cyl_neumann
|
| 7228 |
+
[sf.cmath.ellint_1]: #sf.cmath.ellint_1
|
| 7229 |
+
[sf.cmath.ellint_2]: #sf.cmath.ellint_2
|
| 7230 |
+
[sf.cmath.ellint_3]: #sf.cmath.ellint_3
|
| 7231 |
+
[sf.cmath.expint]: #sf.cmath.expint
|
| 7232 |
+
[sf.cmath.hermite]: #sf.cmath.hermite
|
| 7233 |
+
[sf.cmath.laguerre]: #sf.cmath.laguerre
|
| 7234 |
+
[sf.cmath.legendre]: #sf.cmath.legendre
|
| 7235 |
+
[sf.cmath.riemann_zeta]: #sf.cmath.riemann_zeta
|
| 7236 |
+
[sf.cmath.sph_bessel]: #sf.cmath.sph_bessel
|
| 7237 |
+
[sf.cmath.sph_legendre]: #sf.cmath.sph_legendre
|
| 7238 |
+
[sf.cmath.sph_neumann]: #sf.cmath.sph_neumann
|
| 7239 |
[slice.access]: #slice.access
|
| 7240 |
[slice.arr.assign]: #slice.arr.assign
|
| 7241 |
[slice.arr.comp.assign]: #slice.arr.comp.assign
|
| 7242 |
[slice.arr.fill]: #slice.arr.fill
|
| 7243 |
[strings]: strings.md#strings
|
| 7244 |
[tab:RandomDistribution]: #tab:RandomDistribution
|
| 7245 |
[tab:RandomEngine]: #tab:RandomEngine
|
| 7246 |
[tab:SeedSequence]: #tab:SeedSequence
|
| 7247 |
+
[tab:UniformRandomBitGenerator]: #tab:UniformRandomBitGenerator
|
| 7248 |
+
[tab:copyassignable]: #tab:copyassignable
|
| 7249 |
+
[tab:copyconstructible]: #tab:copyconstructible
|
| 7250 |
+
[tab:equalitycomparable]: #tab:equalitycomparable
|
| 7251 |
[tab:iterator.input.requirements]: iterators.md#tab:iterator.input.requirements
|
| 7252 |
+
[tab:moveassignable]: #tab:moveassignable
|
| 7253 |
+
[tab:moveconstructible]: #tab:moveconstructible
|
|
|
|
|
|
|
| 7254 |
[tab:numerics.lib.summary]: #tab:numerics.lib.summary
|
| 7255 |
[template.gslice.array]: #template.gslice.array
|
| 7256 |
[template.gslice.array.overview]: #template.gslice.array.overview
|
| 7257 |
[template.indirect.array]: #template.indirect.array
|
| 7258 |
[template.indirect.array.overview]: #template.indirect.array.overview
|
|
|
|
| 7261 |
[template.slice.array]: #template.slice.array
|
| 7262 |
[template.slice.array.overview]: #template.slice.array.overview
|
| 7263 |
[template.valarray]: #template.valarray
|
| 7264 |
[template.valarray.overview]: #template.valarray.overview
|
| 7265 |
[thread.thread.class]: thread.md#thread.thread.class
|
| 7266 |
+
[transform.exclusive.scan]: #transform.exclusive.scan
|
| 7267 |
+
[transform.inclusive.scan]: #transform.inclusive.scan
|
| 7268 |
+
[transform.reduce]: #transform.reduce
|
| 7269 |
[valarray.access]: #valarray.access
|
| 7270 |
[valarray.assign]: #valarray.assign
|
| 7271 |
[valarray.binary]: #valarray.binary
|
| 7272 |
[valarray.cassign]: #valarray.cassign
|
| 7273 |
[valarray.comparison]: #valarray.comparison
|
|
|
|
| 7303 |
[^6]: The distribution corresponding to this probability density
|
| 7304 |
function is also known (with a possible change of variable) as the
|
| 7305 |
Gumbel Type I, the log-Weibull, or the Fisher-Tippett Type I
|
| 7306 |
distribution.
|
| 7307 |
|
| 7308 |
+
[^7]: Annex [[implimits]] recommends a minimum number of recursively
|
| 7309 |
nested template instantiations. This requirement thus indirectly
|
| 7310 |
suggests a minimum allowable complexity for valarray expressions.
|
| 7311 |
|
| 7312 |
[^8]: The intent is to specify an array template that has the minimum
|
| 7313 |
functionality necessary to address aliasing ambiguities and the
|
| 7314 |
proliferation of temporaries. Thus, the `valarray` template is
|
| 7315 |
neither a matrix class nor a field class. However, it is a very
|
| 7316 |
useful building block for designing such classes.
|
| 7317 |
|
| 7318 |
+
[^9]: This default constructor is essential, since arrays of `valarray`
|
|
|
|
|
|
|
|
|
|
| 7319 |
may be useful. After initialization, the length of an empty array
|
| 7320 |
can be increased with the `resize` member function.
|
| 7321 |
|
| 7322 |
+
[^10]: This constructor is the preferred method for converting a C array
|
| 7323 |
to a `valarray` object.
|
| 7324 |
|
| 7325 |
+
[^11]: This copy constructor creates a distinct array rather than an
|
| 7326 |
alias. Implementations in which arrays share storage are permitted,
|
| 7327 |
but they shall implement a copy-on-reference mechanism to ensure
|
| 7328 |
that arrays are conceptually distinct.
|
| 7329 |
|
| 7330 |
+
[^12]: BLAS stands for *Basic Linear Algebra Subprograms.* C++programs
|
|
|
|
|
|
|
|
|
|
|
|
|
| 7331 |
may instantiate this class. See, for example, Dongarra, Du Croz,
|
| 7332 |
Duff, and Hammerling: *A set of Level 3 Basic Linear Algebra
|
| 7333 |
Subprograms*; Technical Report MCS-P1-0888, Argonne National
|
| 7334 |
Laboratory (USA), Mathematics and Computer Science Division, August,
|
| 7335 |
1988.
|
| 7336 |
|
| 7337 |
+
[^13]: The use of fully closed ranges is intentional.
|
| 7338 |
+
|
| 7339 |
+
[^14]: `accumulate` is similar to the APL reduction operator and Common
|
| 7340 |
Lisp reduce function, but it avoids the difficulty of defining the
|
| 7341 |
result of reduction on an empty sequence by always requiring an
|
| 7342 |
initial value.
|
| 7343 |
|
| 7344 |
+
[^15]: The use of fully closed ranges is intentional.
|
| 7345 |
|
| 7346 |
+
[^16]: The use of fully closed ranges is intentional.
|
| 7347 |
|
| 7348 |
+
[^17]: The use of fully closed ranges is intentional.
|
| 7349 |
|
| 7350 |
+
[^18]: A mathematical function is mathematically defined for a given set
|
| 7351 |
+
of argument values (a) if it is explicitly defined for that set of
|
| 7352 |
+
argument values, or (b) if its limiting value exists and does not
|
| 7353 |
+
depend on the direction of approach.
|