 # C math library function fabs()

In this article, you will learn about C math library function `fabs()` that returns an absolute value of the number, with explanation and example. `fabs()` is the standard C math library function that is defined in math library `math.h` and it returns the absolute value of number passed as an argument.

``#include<math.h>``

## Function prototype of C math library function fabs()

``double fabs( double n );``

where,

n = floating point argument.

This function returns the absolute value of `n`.

## Example: Program to demonstrate the use of standard C math library function fabs()

``````/*Use of math library function fabs*/

#include<stdio.h>
#include<math.h>

int main()
{
double x, y;

x = 22.3;
y = -22.3;

//displaying actual value
printf("Value of x = %.2lf\n"
"Value of y = %.2lf\n\n", x, y);

//calculating absolute value
printf("Absolute value of x = %.2lf\n"
"Absolute value of y = %.2lf\n", fabs(x), fabs(y));

return 0;
}
``````

Output Explanation

In the above program, we have calculated the absolute value of `x` and `y`.

`%.2lf` is used to display decimal value up to two places.