operator+,-,*,/,%,&,|,^,<<,>>,&&,|| (std::valarray)

std::valarray <T> operator+ ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator- ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator* ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator/ ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator% ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator& ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator| ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator^ ( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator<<( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator>>( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >
std::valarray <bool> operator&&( const std::valarray <T>& lhs, const std::valarray <T>& rhs );
template< class T >

std::valarray <bool> operator||( const std::valarray <T>& lhs, const std::valarray <T>& rhs );

(1)

template< class T >

std::valarray <T> operator+ ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator- ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator* ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator/ ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator% ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator& ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator| ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator^ ( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator<<( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <T> operator>>( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <bool> operator&&( const typename std::valarray <T>::value_type & val,
const std::valarray <T>& rhs );
template< class T >
std::valarray <bool> operator||( const typename std::valarray <T>::value_type & val,

const std::valarray <T>& rhs );

(2)

template< class T >

std::valarray <T> operator+ ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator- ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator* ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator/ ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator% ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator& ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator| ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator^ ( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator<<( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <T> operator>>( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <bool> operator&&( const std::valarray <T>& lhs,
const typename std::valarray <T>::value_type & val );
template< class T >
std::valarray <bool> operator||( const std::valarray <T>& lhs,

const typename std::valarray <T>::value_type & val );

(3)

Apply binary operators to each element of two valarrays, or a valarray and a value.

1) The operators works on valarrays of the same size and returns a valarray with the same size as the parameters with the operation applied to every elements of the two arguments.

2,3) Applies the operator between each element of the valarray and the scalar.

All const member functions of std::valarray are provided.
std::valarray , std::slice_array , std::gslice_array , std::mask_array and std::indirect_array can be constructed from the replacement type.
For every function taking a const std::valarray <T>& except begin() and end() (since C++11), identical functions taking the replacement types shall be added;
For every function taking two const std::valarray <T>& arguments, identical functions taking every combination of const std::valarray <T>& and replacement types shall be added.
The return type does not add more than two levels of template nesting over the most deeply-nested argument type.

[edit] Example

Finds real roots of multiple Quadratic equations.

Run this code

#include <cstddef>
#include <iostream>
#include <valarray>
 
int main()
{
 std::valarray <double> a(1, 8);
 std::valarray <double> b{1, 2, 3, 4, 5, 6, 7, 8};
 std::valarray <double> c = -b;
 // literals must also be of type T until LWG3074 (double in this case)
 std::valarray <double> d = std::sqrt (b * b - 4.0 * a * c);
 std::valarray <double> x1 = 2.0 * c / (-b + d);
 std::valarray <double> x2 = 2.0 * c / (-b - d);
 std::cout << "quadratic equation: root 1: root 2: b: c:\n";
 for (std::size_t i = 0; i < a.size(); ++i)
 std::cout << a[i] << "\u00B7x\u00B2 + " << b[i] << "\u00B7x + "
 << c[i] << " = 0 " << std::fixed << x1[i]
 << " " << x2[i] << std::defaultfloat
 << " " << -x1[i] - x2[i]
 << " " << x1[i] * x2[i] << '\n';
}

Output:

quadratic equation: root 1: root 2: b: c:
1·x2 + 1·x + -1 = 0 -1.618034 0.618034 1 -1
1·x2 + 2·x + -2 = 0 -2.732051 0.732051 2 -2
1·x2 + 3·x + -3 = 0 -3.791288 0.791288 3 -3
1·x2 + 4·x + -4 = 0 -4.828427 0.828427 4 -4
1·x2 + 5·x + -5 = 0 -5.854102 0.854102 5 -5
1·x2 + 6·x + -6 = 0 -6.872983 0.872983 6 -6
1·x2 + 7·x + -7 = 0 -7.887482 0.887482 7 -7
1·x2 + 8·x + -8 = 0 -8.898979 0.898979 8 -8

[edit] 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 3074	C++98	`T` is deduced from both the scalar and the `valarray` for (2,3), disallowing mixed-type calls	only deduce `T` from the `valarray`

[edit] See also

operator+operator-operator~operator!

applies a unary arithmetic operator to each element of the valarray
(public member function) [edit]

operator+=operator-=operator*=operator/=operator%=operator&=operator|=operator^=operator<<=operator>>=

applies compound assignment operator to each element of the valarray
(public member function) [edit]

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operator+,-,*,/,%,&,|,^,<<,>>,&&,|| (std::valarray)

Contents

[edit] Parameters

[edit] Return value

[edit] Note

[edit] Example

[edit] Defect reports

[edit] See also

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