valarray::sum
Determines the sum of all the elements in a valarray of nonzero length.
Type sum( ) const;
Return Value
The sum of the elements of the operand valarray.
Remarks
If the length is greater than one, the member function adds values to the sum by applying operator+= between pairs of elements of class Type, which operator, consequently, needs be provided for elements of type Type.
Example
// valarray_sum.cpp
// compile with: /EHsc
#include <valarray>
#include <iostream>
int main( )
{
using namespace std;
int i;
int sumva = 0;
valarray<int> va ( 10 );
for ( i = 0 ; i < 10 ; i+=1 )
va [ i ] = i;
cout << "The operand valarray va (10) is: ( ";
for ( i = 0 ; i < 10 ; i++ )
cout << va [ i ] << " ";
cout << ")." << endl;
sumva = va.sum ( );
cout << "The sum of elements in the valarray is: "
<< sumva << "." <<endl;
}
The operand valarray va (10) is: ( 0 1 2 3 4 5 6 7 8 9 ).
The sum of elements in the valarray is: 45.
Requirements
Header: <valarray>
Namespace: std