The **`nextafter()`** function is used to produce the smallest possible   value after a number in a given direction. The declaration of `nextafter()` is shown below:
```C
double nextafter (double num, double dir);
```
Or:
```C
long double nextafterl (long double num, long double dir);
```
Or:
```C
float nextafterf (float num, float dir);
```
The `nextafter()` function returns the next representable floating-point number after `num` in the direction of `dir`.

# Library
To use the `nextafter()` function, include the following library:
```C
#include <math.h>
```

# Code
Consider the code snippet below, which demonstrates the implementation of `nextafter()`:

 


#include <stdio.h>
#include <math.h>

int main() {

  double a = 0.0;
  double b = 1.0;

  double x = nextafter(a, b);

  printf("nextafter ( %f, %f ) = ( %e ) \n", a, b, x);
  
  return 0;
}

gcc compiler

# Explanation
The `nextafter()` function is used in line 9 to compute the next representable floating-point number after `a` in the direction of `b`.


gcc.tar.gz

What is nextafter() in C?

The nextafter() function returns the next representable floating-point number after num in dir's direction.