It is defined in <cmath> header file.
[Mathematics] |x| = fabs(x) [C++ Programming]
fabs() prototype [As of C++ 11 standard]
double fabs(double x); float fabs(float x); long double fabs(long double x); double fabs(T x); // For integral type
The fabs() function takes a single argument and returns a value of type double
, float
or long double
type.
fabs() Parameters
The fabs() function takes a single argument, x whose absolute value is returned.
fabs() Return value
The fabs() function returns the absolute value of x i.e. |x|.
Example 1: How fabs() function works in C++?
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
double x = -10.25, result;
result = fabs(x);
cout << "fabs(" << x << ") = |" << x << "| = " << result << endl;
return 0;
}
When you run the program, the output will be:
fabs(-10.25) = |-10.25| = 10.25
Example 2: fabs() function for integral types
#include <iostream>
#include <cmath>
using namespace std;
int main()
{
long int x = -23;
double result;
result = fabs(x);
cout << "fabs(" << x << ") = |" << x << "| = " << result << endl;
return 0;
}
When you run the program, the output will be:
fabs(-23) = |-23| = 23