valarray::operator-=

Subtracts the elements of a specified valarray or a value of the element type, element-wise, from an operand valarray.

valarray<Type>& operator-=(
   const valarray<Type>& _Right
);
valarray<Type>& operator-=(
   const Type& _Right
);

Parameters

• _Right
  The valarray or value of an element type identical to that of the operand valarray that is to be subtracted, element-wise, from the operand valarray.

Return Value

A valarray whose elements are the element-wise difference of the operand valarray and _Right.

Example

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

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

   valarray<int> vaL ( 8 ), vaR ( 8 );
   for ( i = 0 ; i < 8 ; i += 2 )
      vaL [ i ] =  10;
   for ( i = 1 ; i < 8 ; i += 2 )
      vaL [ i ] =  0;
   for ( i = 0 ; i < 8 ; i++ )
      vaR [ i ] =  i;
   
   cout << "The initial 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;

   vaL -= vaR;
   cout << "The element-by-element result of "
        << "the difference is the\n valarray: ( ";
      for ( i = 0 ; i < 8 ; i++ )
         cout << vaL [ i ] << " ";
   cout << ")." << endl;
}

The initial valarray is: ( 10 0 10 0 10 0 10 0 ).
The initial _Right valarray is: ( 0 1 2 3 4 5 6 7 ).
The element-by-element result of the difference is the
 valarray: ( 10 -1 8 -3 6 -5 4 -7 ).

Requirements

Header: <valarray>

Namespace: std

See Also

Concepts

valarray Class

valarray Members