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operator* (<valarray>)

Obtains the element-wise product between corresponding elements of two equally sized valarrays or of between a valarray a specified value.

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 elements are to be multiplied or a specified value to be multiplied with each element of a valarray.

  • _Right
    The second of the two valarrays whose elements are to be multiplied or a specified value to be multiplied with each element of a valarray.

Return Value

A valarray whose elements are the element-wise product of _Left and _Right.

Example

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

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

   valarray<int> vaL ( 8 ), vaR ( 8 );
   valarray<int> vaNE ( 8 );
   for ( i = 0 ; i < 8 ; i += 2 )
      vaL [ i ] =  2;
   for ( i = 1 ; i < 8 ; i += 2 )
      vaL [ i ] =  -1;
   for ( i = 0 ; i < 8 ; i++ )
      vaR [ i ] =  i;
   
   cout << "The initial Left valarray is: ( ";
      for (i = 0 ; i < 8 ; i++ )
         cout << vaL [ i ] << " ";
   cout << ")." << endl;

   cout << "The initial Right valarray is: ( ";
      for (i = 0 ; i < 8 ; i++ )
         cout << vaR [ i ] << " ";
   cout << ")." << endl;

   vaNE = ( vaL * vaR );
   cout << "The element-by-element result of "
        << "the multiplication is the\n valarray: ( ";
      for (i = 0 ; i < 8 ; i++ )
         cout << vaNE [ i ] << " ";
   cout << ")." << endl;
}
The initial Left valarray is: ( 2 -1 2 -1 2 -1 2 -1 ).
The initial Right valarray is: ( 0 1 2 3 4 5 6 7 ).
The element-by-element result of the multiplication is the
 valarray: ( 0 -1 4 -3 8 -5 12 -7 ).

Requirements

Header: <valarray>

Namespace: std