{{keywords>wiki library source code example reference}}
===== fabs =====
<code cpp>
    double fabs(double);
</code>
calculates the absolute number of a given value

===== cpp Sourcecode Example =====
<code cpp>     
#include <iostream> /* including standard library */
#include <cmath> /* including math library */

using namespace std;
int main ( void ) 
{
    double y,x;
    x = 4.2422;
    y = -3284.2;

    //cout.setf(ios::fixed, ios::floatfield);
    cout.precision(8);

    cout << "the fabs of 4.2422 is " << fabs(x) << endl;
    cout << "and the fabs of -3284.2 is " <<  fabs(y) << endl;
    return 0;
}

</code>

==== output ====
   the fabs of 4.2422 is 4.2422
   and the fabs of -3284.2 is 3284.2