std::swap(std::valarray)

 

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valarray::valarray valarray::~valarray valarray::operator= valarray::operator[] valarray::swap valarray::size valarray::resize valarray::sum valarray::min valarray::max valarray::shift valarray::cshift valarray::apply	valarray::operator+valarray::operator-valarray::operator~valarray::operator! valarray::operator+=valarray::operator-=valarray::operator*=valarray::operator/=valarray::operator%=valarray::operator&=valarray::operator|=valarray::operator^=valarray::operator<<=valarray::operator>>=
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swap(std::valarray) (C++11) begin(std::valarray) (C++11)   end(std::valarray) (C++11) abs exp log log10 pow sqrt sin cos tan asin acos atan atan2 sinh cosh tanh	operator*operator/operator%operator+operator-operator^operator&operator|operator<<operator>>operator&&operator|| operator==operator!=operator<operator>operator<=operator>=
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Defined in header <valarray>
template< class T > void swap( std::valarray<T>& lhs, std::valarray<T>& rhs ) noexcept;		(since C++11)

Specializes the std::swap algorithm for std::valarray. Swaps the contents of lhs and rhs. Calls lhs.swap(rhs).

Parameters

lhs, rhs

-

valarrays whose contents to swap

Return value

(none)

Complexity

Constant.

Example

Run this code

#include <iostream>
#include <valarray>
 
void print(auto rem, const std::valarray<int>& v)
{
    std::cout << rem << '{';
    for (char sep[]{0, ' ', 0}; auto elem : v)
        std::cout << sep << elem, *sep = ',';
    std::cout << "}\n";
}
 
int main()
{
    std::valarray x{3, 1, 4, 1, 5};
    std::valarray y{2, 7, 1, 8};
 
    print("Before swap:\n" "x: ", x);
    print("y: ", y);
 
    std::swap(x, y);
 
    print("After swap:\n" "x: ", x);
    print("y: ", y);
}

Output:

Before swap:
x: {3, 1, 4, 1, 5}
y: {2, 7, 1, 8}
After swap:
x: {2, 7, 1, 8}
y: {3, 1, 4, 1, 5}

See also

swap	swaps with another valarray (public member function)