Expert: vijayan - 3/18/2009

Question
I want to know how can we print only the magnitude of any floating point value that is assigned to a variable.
For e.g.
a= -45.55
and i want only the magnitude i.e 45.55 to be printed not its sign, so what should be done for this?


Answer
this is easy, isn't it?

one way is to print -a if a is negetive, +a otherwise.
another way is to use the function std::fabs() declared in <cmath> which returns the absolute value of a floating point number.

#include <cmath>
#include <iostream>

int main()
{
     double a = -45.55 ;

     std::cout << ( a < 0.0 ? -a : a ) << '\n'
               << std::fabs(a) << '\n' ;
}