C++ How to use fabs() function and example

C++ Library Function <cmath>

C ++The fabs() function returns the absolute value of the parameter.

It is<cmath>Defined in the header file.

|x| = fabs(x)

fabs() prototype [from C ++ 11Standard begins]

double fabs(double x);
float fabs(float x);
long double fabs(long double x);
double fabs(T x);　//　For integral type

The fabs() function has only one parameter and returns a value of type double, float, or long double.

fabs() parameters

The fabs() function uses a single parameter x and returns its absolute value.

fabs() return value

The fabs() function returns the absolute value of x, that is, |x|.

Example1：The fabs() function in C ++How does it work 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 running the program, the output is:

fabs(-10.25)　=　|-10.25|　=　10.25

Example2：The fabs() function of integer type

#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 running the program, the output is:

fabs(-23)　=　|-23|　=　23

C++ Library Function <cmath>