In this C++ tutorial, you will learn how to find absolute value of given number using fabs() function of cmath, with syntax and examples.
C++ fabs()
C++ fabs() returns absolute value of given argument.
Syntax
The syntax of C++ fabs() is
fabs(x)
where
| Parameter | Description |
|---|---|
| x | A double, float, long double, or integral type value. |
Returns
The return value depends on the type of value passed for parameter x.
The return value of fabs(x) is
- double if x is double or integral type value.
- float if x is float.
- long double if x is long double.
The synopsis of fabs() function is
double fabs(double x); float fabs(float x); long double fabs(long double x); double fabs(T x); // for integral type argument value
fabs() is a function of cmath library. Include cmath library at the start of program, if using fabs() function.
Example
In this example, we read a value from user into variable x, and find the absolute value of x using fabs() function.
C++ Program
#include <iostream>
#include<cmath>
using namespace std;
int main() {
double x;
cout << "Enter a value : ";
cin >> x;
double result = fabs(x);
cout << "fabs(" << x << ") : " << result << endl;
} Output
Enter a value : -52 fabs(-52) : 52 Program ended with exit code: 0
Run#2
Absolute value of a positive number is itself.
Enter a value : 25 fabs(25) : 25 Program ended with exit code: 0
Conclusion
In this C++ Tutorial, we learned the syntax of C++ fabs(), and how to use this function to find the absolute of a value, with the help of examples.