Dela via


operator== (<valarray>)

Tests whether the corresponding elements of two equally sized valarrays are equal or whether all the elements of a valarray are equal a specified value.

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
  );

Parameters

  • _Left
    The first of the two valarrays whose elements are to be tested for equality.

  • _Right
    The second of the two valarrays whose elements are to be tested for equality.

Return Value

A valarray of Boolean values, each of which is:

  • true if the corresponding elements are equal.

  • false if the corresponding elements are not equal.

Remarks

The first template operator returns an object of class valarray<bool>, each of whose elements I is _Left[I] == _Right[I]. The second template operator stores in element I _Left[I] == _Right. The third template operator stores in element I _Left == _Right[I].

Example

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

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

   valarray<int> vaL ( 10 ), vaR ( 10 );
   valarray<bool> vaNE ( 10 );
   for ( i = 0 ; i < 10 ; i += 2 )
      vaL [ i ] =  -i;
   for ( i = 1 ; i < 10 ; i += 2 )
      vaL [ i ] =  i;
   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;

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

Requirements

Header: <valarray>

Namespace: std

See Also

Reference

stack::operator==

Other Resources

<valarray> Members