trunc Function

Rounds the argument rounded to an integer value no large than the argument value.

Include

<math.h>

Prototype

double trunc(double x);

Argument

x
the value to round

Return Value

Returns the value of x rounded to the nearest integer value that is no larger in magnitude that the original argument. The rounded integer is returned as a double precision floating-point value.

Example

See the notes at the beginning of this chapter or section for information on using printf() or scanf() (and other functions reading and writing the stdin or stdout streams) in the example code.

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

int main(void)
{
  double x, y;

  x = -10.103;
  y = trunc(x);
  printf("The nearest integer value to %f is %f\n", x, y);

  x = 10.9;
  y = trunc(x);
  printf("The nearest integer value to %f is %f\n", x, y);
}

Example Output

The nearest integer value to -10.103000 is -10.000000
The nearest integer value to 10.900000 is 10.000000