std::indirect_array<T>::operator=

 

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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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slice_array gslice_array indirect_array	slice gslice mask_array
Deduction guides(C++17)

 

std::indirect_array

Member functions

indirect_array::indirect_array

indirect_array::~indirect_array

indirect_array::operator=

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

 

void operator=(const T& value )const;	(1)
void operator=(conststd::valarray<T>& val_arr )const;	(2)
const indirect_array& operator=(const indirect_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::indirect_array to assign

Return value

1,2) (none)

3)*this

Example

Run this code

#include <iomanip>#include <iostream>#include <numeric>#include <valarray>   void print(int n, std::valarray<int>const& v){std::cout<< n <<':';for(int e : v)std::cout<<std::setw(3)<< e;std::cout<<'\n';}   int main(){std::valarray<int> v(8);std::iota(std::begin(v), std::end(v), 0); print(1, v);   std::valarray<std::size_t> idx{1, 3, 5, 7};conststd::indirect_array<int> ia = v[idx];// 'ia' refers to v[1], v[3], v[5], v[7] ia =-1;// (1), effectively:// v[1] = v[3] = v[5] = v[7] = -1; print(2, v);   ia =/*std::valarray<int>*/{-1, -2, -3, -4};// (2),// effectively: v[1] = -1, v[3] = -2, v[5] = -3, v[7] = -4; print(3, v);   std::valarray<std::size_t> idx2{0, 2, 4, 6};conststd::indirect_array<int> ia2 = v[idx2];// 'ia2' refers to v[0], v[2], v[4], v[6] ia = ia2;// (3), effectively:// v[1] = v[0], v[3] = v[2], v[5] = v[4], v[7] = v[6]; print(4, v);}

Output:

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

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