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abs (<valarray>)

Operates on the elements of an input valarray, returning a valarray whose elements are equal to the absolute value of the elements of the input valarray.

template<class Type> 
   valarray<Type> abs( 
      const valarray<Type>& _Left 
   );

Parameters

  • _Left
    The input valarray whose elements are to be operated on by the member function.

Return Value

A valarray whose elements are equal to the absolute value of the elements of the input valarray.

Example

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

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

   valarray<int> va1 ( 9 ), va2 ( 9 );
   for ( i = 0 ; i < 4 ; i++ )
      va1 [ i ] =  -i;
   for ( i = 4 ; i < 9 ; i++ )
      va1 [ i ] =  i;

   cout << "The initial valarray is: ";
      for (i = 0 ; i < 9 ; i++ )
         cout << va1 [ i ] << " ";
   cout << "." << endl;

   va2 = abs ( va1 );
   cout << "The absolute value of the initial valarray is: ";
      for (i = 0 ; i < 9 ; i++ )
         cout << va2 [ i ] << " ";
   cout << "." << endl;
}
The initial valarray is: 0 -1 -2 -3 4 5 6 7 8 .
The absolute value of the initial valarray is: 0 1 2 3 4 5 6 7 8 .

Requirements

Header: <valarray>

Namespace: std

See Also

Reference

abs (STL Samples)