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operator&&

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

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

_Left

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

_Right

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

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

The logical AND operator&& applies on an element level, counting all nonzero values as true, and the result is a valarray of Boolean values. The bitwise version of AND, operator&,, by contrast, can result in a valarray of values other than 0 or 1, depending on the outcome of the bitwise operation.

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

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

   valarray<int> vaL ( 10 ), vaR ( 10 );
   valarray<bool> vaLAA ( 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;

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

Header: <valarray>

Namespace: std

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