std::mask_array<T>::operator=

 

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std::valarray

Member functions
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>>=
Non-member functions
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>=
Helper classes
slice_array gslice_array indirect_array	slice gslice mask_array
Deduction guides(C++17)

 

std::mask_array

Member functions

mask_array::mask_array

mask_array::~mask_array

mask_array::operator=

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

 

void operator=(const T& value )const;	(1)
void operator=(conststd::valarray<T>& val_arr )const;	(2)
const mask_array& operator=(const mask_array& other_arr )const;	(3)

Assigns values to all referred elements.

1) Assigns value to all of the elements.

2) Assigns the elements of val_arr to the referred to elements of *this.

3) Assigns the selected elements from other_arr to the referred to elements of *this.

Parameters

value	-	a value to assign to all of the referred elements
val_arr	-	std::valarray to assign
other_arr	-	std::mask_array to assign

Return value

1,2) (none)

3)*this

Example

Run this code

#include <iomanip>#include <iostream>#include <valarray>   void print(std::valarray<int>const& v){for(int e : v)std::cout<<std::setw(2)<< e <<' ';std::cout<<'\n';}   int main(){constauto init ={1, 2, 3, 4, 5, 6, 7, 8};std::valarray<int> v;   v = init; v[(v %2)==0]=0;// (1) print(v);   v = init; v[(v %2)==1]=std::valarray<int>{-1, -2, -3, -4};// (2) print(v);   v = init; v[(v %2)==0]= v[(v %2)==1];// (3) print(v);}

Output:

 1 0 3 0 5 0 7 0 -1 2 -2 4 -3 6 -4 8 1 1 3 3 5 5 7 7

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 123	C++98	overload (2) was non-const	made const
LWG 253	C++98	the copy assignment operator was private	made public
LWG 621	C++98	the copy assignment operator was non-const	made const