The abs()
function in C++ returns the absolute value of the argument. It is defined in the cmath header file.
Mathematically, abs(num) = |num|
.
Example
#include <iostream>
#include <cmath>
using namespace std;
int main() {
// get absolute value of -5.5
cout << abs(-5.5);
return 0;
}
// Output: 5.5
Syntax of abs()
The syntax of the abs()
function is:
abs(double num);
abs() Parameters
The abs()
function takes the following parameter:
- num - a floating point number whose absolute value is returned. It can be of the following types:
double
float
long double
abs() Return Value
The abs()
function returns:
- the absolute value of num i.e.
|num|
abs() Prototypes
The prototypes of abs()
as defined in the cmath header file are:
double abs(double num);
float abs(float num);
long double abs(long double num);
// for integral types
double abs(T num);
Note: The cmath abs()
function is identical to the fabs() function.
Example 1: C++ abs()
#include <iostream>
#include <cmath>
using namespace std;
int main() {
double num = -87.91, result;
result = abs(num);
cout << "abs(" << num << ") = |" << num << "| = " << result;
return 0;
}
Output
abs(-87.91) = |-87.91| = 87.91
Example 2: C++ abs() for Integral Types
#include <iostream>
#include <cmath>
using namespace std;
int main() {
int num = -101;
double result;
result = abs(num);
cout << "abs(" << num << ") = |" << num << "| = " << result;
return 0;
}
Output
abs(-101) = |-101| = 101