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operator&

Obtains the bitwise AND between corresponding elements of two equally sized valarrays or between a valarray and a specified value of the element type.

template<class Type>
   valarray<Type> operator&(
      const valarray<Type>& _Left,
      const valarray<Type>& _Right
   );
template<class Type>
   valarray<Type> operator&(
      const valarray<Type>& _Left,
      const Type& _Right
   );
template<class Type>
   valarray<Type> operator&(
      const Type& _Left,
      const valarray<Type>& _Right
   );

Parameters

  • _Left
    The first of the two valarrays whose respective elements are to be combined with the bitwise AND or a specified value of the element type to be combined bitwise with each element of a valarray.

  • _Right
    The second of the two valarrays whose respective elements are to be combined with the bitwise AND or a specified value of the element type to be combined bitwise with each element of a valarray.

Return Value

A valarray whose elements are the element-wise combination of the bitwise AND operation of _Left and _Right.

Remarks

A bitwise operation can only be used to manipulate bits in char and int data types and variants and not on float, double, long double, void bool or other, more complex data types.

The bitwise AND has the same truth table as the logical AND but applies to the data type on the level of the individual bits. The operator&& applies on an element level, counting all nonzero values as true, and the result is a valarray of Boolean values. The bitwise AND operator&, by contrast, can result in a valarray of values other than 0 or 1, depending on outcome of the bitwise operation.

Example

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

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

   valarray<int> vaL ( 10 ), vaR ( 10 );
   valarray<int> vaBWA ( 10 );
   for ( i = 0 ; i < 10 ; i += 2 )
      vaL [ i ] =  0;
   for ( i = 1 ; i < 10 ; i += 2 )
      vaL [ i ] =  i+1;
   for ( i = 0 ; i < 10 ; i++ )
      vaR [ i ] =  i;
   
   cout << "The initial Left valarray is:  ( ";
      for ( i = 0 ; i < 10 ; i++ )
         cout << vaL [ i ] << " ";
   cout << ")." << endl;

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

   vaBWA = ( vaL & vaR );
   cout << "The element-by-element result of "
        << "the bitwise operator & is the\n valarray: ( ";
      for ( i = 0 ; i < 10 ; i++ )
         cout << vaBWA [ i ] << " ";
   cout << ")." << endl;
}
The initial Left valarray is:  ( 0 2 0 4 0 6 0 8 0 10 ).
The initial Right valarray is: ( 0 1 2 3 4 5 6 7 8 9 ).
The element-by-element result of the bitwise operator & is the
 valarray: ( 0 0 0 0 0 4 0 0 0 8 ).

Requirements

Header: <valarray>

Namespace: std