# fmod() function in C++ and its uses

In this section, we will learn the concept of fmod() function and understand its implementation with an example.

## fmod() function in C++

• In C++ there are various types of inbuilt function which helps us to perform a mathematical operation on floating-point numbers.
• The fmod() function is one of those inbuilt functions in the <`cmath`> header file which is used to return the remainder or the modulus of two floating-point numbers. It accepts 2 numbers as numerator and denominator and calculates the reminder rounded towards zero.
• The function returns the value of type double which is the floating-point modulus of the division.

Syntax:

```double fmod(double a, double b);

//Where a = Numerator and b = Denominator

//The function returns the reminder of dividing a/b.```

Note: To perform a valid operation using fmod() function, the denominator value should always be greater than 0, otherwise it will return a null value.

## Example program for fmod() function

Let’s understand the use of fmod() with an example:

```#include <iostream>
#include <cmath>
using namespace std;

int main()
{
double a,b,reminder;

//Input the value of numerator and denominator

cout << "Enter the numerator value:" << endl;
cin >> a;

cout << "Enter the denominator value:" << endl;
cin >> b;

reminder = fmod(a, b); //function call
cout << "Remainder of " << a << "/" << b << " = " << reminder << endl;

//Let's take the denominator 0
b = 0;
reminder = fmod(a, b); //function call
cout << "Remainder of " << a << "/" << b << " = " << reminder << endl;

return 0;
}```

#### Output:

```Enter the numerator value:
7.8
Enter the denominator value:
9.4
Remainder of 7.8/9.4 = 7.8
Remainder of 7.8/0 = -nan
```

Hope this article has helped you to understand the fmod( ) function and its uses in C++.

Happy Coding!!!

You can also read, Mathematical functions in C++