C++ Math modf() Function

by Online Tutorials Library July 22, 2022

C++ Math modf()

This function is used to divide a number into integral and fractional part.

For example :

Syntax

Suppose a number is ‘x’ and ‘ptr’ is the pointer to an integral part.

  float modf(float x, float* ptr);  double modf(double x, double* ptr);  long double modf(long double x, long double* ptr);  double modf(integral x, double* ptr);  

Parameter

x: The value which is to be broken into two parts i.e(fractional and integral part).

ptr: It is the pointer to an object where the integral part of x is stored.

Return value

It returns the integral part of x.

Example 1

Let’s see a simple example

  #include <iostream>  #include<math.h>  using namespace std;  int main()  {   float x=18.26;   double ptr;   float i=modf(x,&ptr);   std::cout << “Value of x is : ” <<x <<std::endl;   cout<<“integral part of x is :”<<ptr<<‘n’ ;   cout<<“fractional part of x is :”<<i;   return 0;  }  

Output:

Value of x is : 18.26  integral part of x is :18  fractional part of x is :0.26

In this example, modf() function breaks a number into fractional and integral part. Fractional part is 0.26 and integral part is 18.

Example 2

Let’s see a simple example when the value of x is negative.

  #include <iostream>  #include<math.h>  using namespace std;  int main()  {      float x= -78.34;      double ptr;      float n=modf(x,&ptr);      std::cout << “Value of x is : ” <<x <<std::endl;      cout<<“integral part of x is :”<<ptr<<‘n’ ;      cout<<“fractional part of x is :”<<n;      return 0;  }   

Output:

Value of x is : -78.34  integral part of x is :-78  fractional part of x is :-0.339996

Next TopicC++ Math Functions

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