Standard library header <valarray>

 

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This header is part of the numeric library.

Includes
<initializer_list> (C++11)	std::initializer_list class template
Classes
valarray	Numeric arrays and array slices (class template)
slice	BLAS-like slice of a valarray: starting index, length, stride (class)
slice_array	proxy to a subset of a valarray after applying a slice (class template)
gslice	generalized slice of a valarray: starting index, set of lengths, set of strides (class)
gslice_array	proxy to a subset of a valarray after applying a gslice (class template)
mask_array	proxy to a subset of a valarray after applying a boolean mask operator[] (class template)
indirect_array	proxy to a subset of a valarray after applying indirect operator[] (class template)
Functions
Operations
std::swap(std::valarray) (C++11)	specializes the std::swap algorithm (function template)
std::begin(std::valarray) (C++11)	overloads std::begin (function template)
std::end(std::valarray) (C++11)	specializes std::end (function template)
operator+operator-operator*operator/operator%operator&operator|operator^operator<<operator>>operator&&operator||	applies binary operators to each element of two valarrays, or a valarray and a value (function template)
operator==operator!=operator<operator<=operator>operator>=	compares two valarrays or a valarray with a value (function template)
abs(std::valarray)	applies the function abs to each element of valarray (function template)
Exponential functions
exp(std::valarray)	applies the function std::exp to each element of valarray (function template)
log(std::valarray)	applies the function std::log to each element of valarray (function template)
log10(std::valarray)	applies the function std::log10 to each element of valarray (function template)
Power functions
pow(std::valarray)	applies the function std::pow to two valarrays or a valarray and a value (function template)
sqrt(std::valarray)	applies the function std::sqrt to each element of valarray (function template)
Trigonometric functions
sin(std::valarray)	applies the function std::sin to each element of valarray (function template)
cos(std::valarray)	applies the function std::cos to each element of valarray (function template)
tan(std::valarray)	applies the function std::tan to each element of valarray (function template)
asin(std::valarray)	applies the function std::asin to each element of valarray (function template)
acos(std::valarray)	applies the function std::acos to each element of valarray (function template)
atan(std::valarray)	applies the function std::atan to each element of valarray (function template)
atan2(std::valarray)	applies the function std::atan2 to a valarray and a value (function template)
Hyperbolic functions
sinh(std::valarray)	applies the function std::sinh to each element of valarray (function template)
cosh(std::valarray)	applies the function std::cosh to each element of valarray (function template)
tanh(std::valarray)	applies the function std::tanh to each element of valarray (function template)

Synopsis

#include <initializer_list>   namespace std {template<class T>class valarray;// An array of type Tclass slice;// a BLAS-like slice out of an arraytemplate<class T>class slice_array;class gslice;// a generalized slice out of an arraytemplate<class T>class gslice_array;template<class T>class mask_array;// a masked arraytemplate<class T>class indirect_array;// an indirected array   template<class T>void swap(valarray<T>&, valarray<T>&)noexcept;   template<class T> valarray<T> operator*(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator*(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator*(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator/(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator/(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator/(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator%(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator%(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator%(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator+(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator+(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator+(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator-(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator-(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator-(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator^(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator^(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator^(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator&(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator&(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator&(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator|(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator|(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator|(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator<<(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator<<(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator<<(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> operator>>(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> operator>>(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> operator>>(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<bool> operator&&(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator&&(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator&&(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<bool> operator||(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator||(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator||(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<bool> operator==(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator==(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator==(consttypename valarray<T>::value_type&, const valarray<T>&);template<class T> valarray<bool> operator!=(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator!=(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator!=(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<bool> operator<(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator<(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator<(consttypename valarray<T>::value_type&, const valarray<T>&);template<class T> valarray<bool> operator>(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator>(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator>(consttypename valarray<T>::value_type&, const valarray<T>&);template<class T> valarray<bool> operator<=(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator<=(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator<=(consttypename valarray<T>::value_type&, const valarray<T>&);template<class T> valarray<bool> operator>=(const valarray<T>&, const valarray<T>&);template<class T> valarray<bool> operator>=(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<bool> operator>=(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> abs (const valarray<T>&);template<class T> valarray<T> acos (const valarray<T>&);template<class T> valarray<T> asin (const valarray<T>&);template<class T> valarray<T> atan (const valarray<T>&);   template<class T> valarray<T> atan2(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> atan2(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> atan2(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> cos (const valarray<T>&);template<class T> valarray<T> cosh (const valarray<T>&);template<class T> valarray<T> exp (const valarray<T>&);template<class T> valarray<T> log (const valarray<T>&);template<class T> valarray<T> log10(const valarray<T>&);   template<class T> valarray<T> pow(const valarray<T>&, const valarray<T>&);template<class T> valarray<T> pow(const valarray<T>&, consttypename valarray<T>::value_type&);template<class T> valarray<T> pow(consttypename valarray<T>::value_type&, const valarray<T>&);   template<class T> valarray<T> sin (const valarray<T>&);template<class T> valarray<T> sinh (const valarray<T>&);template<class T> valarray<T> sqrt (const valarray<T>&);template<class T> valarray<T> tan (const valarray<T>&);template<class T> valarray<T> tanh (const valarray<T>&);   template<class T>/* unspecified1 */ begin(valarray<T>& v);template<class T>/* unspecified2 */ begin(const valarray<T>& v);template<class T>/* unspecified1 */ end(valarray<T>& v);template<class T>/* unspecified2 */ end(const valarray<T>& v);}

Class template std::valarray

namespace std {template<class T>class valarray {public:using value_type = T;   // construct/destroy valarray();explicit valarray(size_t); valarray(const T&, size_t); valarray(const T*, size_t); valarray(const valarray&); valarray(valarray&&)noexcept; valarray(const slice_array<T>&); valarray(const gslice_array<T>&); valarray(const mask_array<T>&); valarray(const indirect_array<T>&); valarray(initializer_list<T>); ~valarray();   // assignment valarray& operator=(const valarray&); valarray& operator=(valarray&&)noexcept; valarray& operator=(initializer_list<T>); valarray& operator=(const T&); valarray& operator=(const slice_array<T>&); valarray& operator=(const gslice_array<T>&); valarray& operator=(const mask_array<T>&); valarray& operator=(const indirect_array<T>&);   // element accessconst T& operator[](size_t)const; T& operator[](size_t);   // subset operations valarray operator[](slice)const; slice_array<T> operator[](slice); valarray operator[](const gslice&)const; gslice_array<T> operator[](const gslice&); valarray operator[](const valarray<bool>&)const; mask_array<T> operator[](const valarray<bool>&); valarray operator[](const valarray<size_t>&)const; indirect_array<T> operator[](const valarray<size_t>&);   // unary operators valarray operator+()const; valarray operator-()const; valarray operator~()const; valarray<bool> operator!()const;   // compound assignment valarray& operator*=(const T&); valarray& operator/=(const T&); valarray& operator%=(const T&); valarray& operator+=(const T&); valarray& operator-=(const T&); valarray& operator^=(const T&); valarray& operator&=(const T&); valarray& operator|=(const T&); valarray& operator<<=(const T&); valarray& operator>>=(const T&);   valarray& operator*=(const valarray&); valarray& operator/=(const valarray&); valarray& operator%=(const valarray&); valarray& operator+=(const valarray&); valarray& operator-=(const valarray&); valarray& operator^=(const valarray&); valarray& operator|=(const valarray&); valarray& operator&=(const valarray&); valarray& operator<<=(const valarray&); valarray& operator>>=(const valarray&);   // member functionsvoid swap(valarray&)noexcept;   size_t size()const;   T sum()const; T min()const; T max()const;   valarray shift (int)const; valarray cshift(int)const; valarray apply(T func(T))const; valarray apply(T func(const T&))const;void resize(size_t sz, T c = T());};   template<class T, size_t cnt> valarray(const T(&)[cnt], size_t)-> valarray<T>;}

Class std::slice

namespace std {class slice {public: slice(); slice(size_t, size_t, size_t);   size_t start()const; size_t size()const; size_t stride()const;   friendbool operator==(const slice& x, const slice& y);};}

Class template std::slice_array

namespace std {template<class T>class slice_array {public:using value_type = T;   void operator=(const valarray<T>&)const;void operator*=(const valarray<T>&)const;void operator/=(const valarray<T>&)const;void operator%=(const valarray<T>&)const;void operator+=(const valarray<T>&)const;void operator-=(const valarray<T>&)const;void operator^=(const valarray<T>&)const;void operator&=(const valarray<T>&)const;void operator|=(const valarray<T>&)const;void operator<<=(const valarray<T>&)const;void operator>>=(const valarray<T>&)const;   slice_array(const slice_array&); ~slice_array();const slice_array& operator=(const slice_array&)const;void operator=(const T&)const;   slice_array()= delete;// as implied by declaring copy constructor above};}

Class std::gslice

namespace std {class gslice {public: gslice(); gslice(size_t s, const valarray<size_t>& l, const valarray<size_t>& d);   size_t start()const; valarray<size_t> size()const; valarray<size_t> stride()const;};}

Class template std::gslice_array

namespace std {template<class T>class gslice_array {public:using value_type = T;   void operator=(const valarray<T>&)const;void operator*=(const valarray<T>&)const;void operator/=(const valarray<T>&)const;void operator%=(const valarray<T>&)const;void operator+=(const valarray<T>&)const;void operator-=(const valarray<T>&)const;void operator^=(const valarray<T>&)const;void operator&=(const valarray<T>&)const;void operator|=(const valarray<T>&)const;void operator<<=(const valarray<T>&)const;void operator>>=(const valarray<T>&)const;   gslice_array(const gslice_array&); ~gslice_array();const gslice_array& operator=(const gslice_array&)const;void operator=(const T&)const;   gslice_array()= delete;// as implied by declaring copy constructor above};}

Class template std::mask_array

namespace std {template<class T>class mask_array {public:using value_type = T;   void operator=(const valarray<T>&)const;void operator*=(const valarray<T>&)const;void operator/=(const valarray<T>&)const;void operator%=(const valarray<T>&)const;void operator+=(const valarray<T>&)const;void operator-=(const valarray<T>&)const;void operator^=(const valarray<T>&)const;void operator&=(const valarray<T>&)const;void operator|=(const valarray<T>&)const;void operator<<=(const valarray<T>&)const;void operator>>=(const valarray<T>&)const;   mask_array(const mask_array&); ~mask_array();const mask_array& operator=(const mask_array&)const;void operator=(const T&)const;   mask_array()= delete;// as implied by declaring copy constructor above};}

Class template std::indirect_array

namespace std {template<class T>class indirect_array {public:using value_type = T;   void operator=(const valarray<T>&)const;void operator*=(const valarray<T>&)const;void operator/=(const valarray<T>&)const;void operator%=(const valarray<T>&)const;void operator+=(const valarray<T>&)const;void operator-=(const valarray<T>&)const;void operator^=(const valarray<T>&)const;void operator&=(const valarray<T>&)const;void operator|=(const valarray<T>&)const;void operator<<=(const valarray<T>&)const;void operator>>=(const valarray<T>&)const;   indirect_array(const indirect_array&); ~indirect_array();const indirect_array& operator=(const indirect_array&)const;void operator=(const T&)const;   indirect_array()= delete;// as implied by declaring copy constructor above};}

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 125	C++98	the return type of valarray<T>::operator!() was valarray<T> in the synopsis	corrected to valarray<bool>