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valarray::operator=

Assigns elements to a valarray whose values are specified either directly or as part of some other valarray or by a slice_array, gslice_array, mask_array, or indirect_array.

valarray<Type>& operator=( 
   const valarray<Type>& _Right 
); 
valarray<Type>& operator=( 
   valarray<Type>&& _Right 
); 
valarray<Type>& operator=( 
   const Type& _Val 
); 
valarray<Type>& operator=( 
   const slice_array<Type>& _Slicearray 
); 
valarray<Type>& operator=( 
   const gslice_array<Type>& _Gslicearray 
); 
valarray<Type>& operator=( 
   const mask_array<Type>& _Maskarray 
); 
valarray<Type>& operator=( 
   const indirect_array<Type>& _Indarray 
);

Parameters

  • _Right
    The valarray to be copied into the operand valarray.

  • _Val
    The value to be assigned to the elements of the operand valarray.

  • _Slicearray
    The slice_array to be copied into the operand valarray.

  • _Gslicearray
    The gslice_array to be copied into the operand valarray.

  • _Maskarray
    The mask_array to be copied into the operand valarray.

  • _Indarray
    The indirect_array to be copied into the operand valarray.

Return Value

The first member operator replaces the controlled sequence with a copy of the sequence controlled by _Right.

The second member operator is the same as the first, but with an Rvalue Reference Declarator: &&.

The third member operator replaces each element of the controlled sequence with a copy of _Val.

The remaining member operators replace those elements of the controlled sequence selected by their arguments, which are generated only by operator[].

If the value of a member in the replacement controlled sequence depends on a member in the initial controlled sequence, the result is undefined.

Remarks

If the length of the controlled sequence changes, the result is generally undefined. In this implementation, however, the effect is merely to invalidate any pointers or references to elements in the controlled sequence.

Example

// valarray_op_assign.cpp
// compile with: /EHsc
#include <valarray>
#include <iostream>

int main( )
{
   using namespace std;
   int i;

   valarray<int> va ( 10 ), vaR ( 10 );
   for ( i = 0 ; i < 10 ; i += 1 )
      va [ i ] = i;
   for ( i = 0 ; i < 10 ; i+=1 )
      vaR [ i ] = 10 -  i;

   cout << "The operand valarray va is:";
   for ( i = 0 ; i < 10 ; i++ )
      cout << " " << va [ i ];
   cout << endl;

   cout << "The operand valarray vaR is:";
      for ( i = 0 ; i < 10 ; i++ )
         cout << " " << vaR [ i ];
   cout << endl;

   // Assigning vaR to va with the first member functon
   va = vaR;
   cout << "The reassigned valarray va is:";
   for ( i = 0 ; i < 10 ; i++ )
      cout << " " << va [ i ];
   cout << endl;

   // Assigning elements of value 10 to va
   // with the second member functon
   va = 10;
   cout << "The reassigned valarray va is:";
      for ( i = 0 ; i < 10 ; i++ )
         cout << " " << va [ i ];
   cout << endl;
}
The operand valarray va is: 0 1 2 3 4 5 6 7 8 9
The operand valarray vaR is: 10 9 8 7 6 5 4 3 2 1
The reassigned valarray va is: 10 9 8 7 6 5 4 3 2 1
The reassigned valarray va is: 10 10 10 10 10 10 10 10 10 10

Requirements

Header: <valarray>

Namespace: std

See Also

Reference

valarray Class