In this C++ tutorial, you will learn how to round given number to nearest integral value using nearbyint() function of cmath, with syntax and examples.
C nearbyint
C++ nearbyint(x) rounds argument x to nearest integral value, using current rounding mode.
The current rounding mode can be accessed using fesetround() and fegetround().
Syntax
The syntax of C++ nearbyint() is
nearbyint(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 nearbyint(x) is
- double if x is double or integral type.
- float if x is float.
- long double if x is long double.
The synopsis of nearbyint() function is
double sinh(double x); float sinh(float x); long double sinh(long double x); double sinh(T x); // for integral type argument values
nearbyint() is a function of cmath library. Include cmath library at the start of program, if using nearbyint() function.
Example
In this example, we read a value from user into variable x, and find the nearest integral value of x using nearbyint() function.
C++ Program
#include <iostream>
#include<cmath>
using namespace std;
int main() {
double x;
cout << "Enter x : ";
cin >> x;
double result = nearbyint(x);
cout << "nearbyint(" << x << ") : " << result << endl;
}
Output
Enter x : 5.23 nearbyint(5.23) : 5 Program ended with exit code: 0
Enter x : 9.89 nearbyint(9.89) : 10 Program ended with exit code: 0
Enter x : nan nearbyint(nan) : nan Program ended with exit code: 0
Conclusion
In this C++ Tutorial, we learned the syntax of C++ nearbyint(), and how to use this function to find the nearest integral value, with the help of examples.