floating-point remainder function

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INTERFACE

#include <math.h>

double fmod ( double x, double y ) long fmodl ( long double x, long double y ) float fmodf ( float x, float y )

DESCRIPTION

The fmod functions compute the floating-point remainder of dividing x by y.

The return value is x - n y, where n is the quotient of x / y, rounded to the first integer towards zero.

Example 1

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

int main(void)
{
  double x = 2*3.1415926 + 0.14527, y = 3.1415926;
  printf("fmod(x, y) = %.5lf\n", fmod(x, y));
  return 0;
}

Output:

fmod(x, y) = 0.14527

SPECIAL VALUES

fmod ( &plusmn;0, y ) returns &plusmn;0 for y not zero.
fmod ( x, y ) returns a NaN and raises the invalid floating-point exception for x infinite or y zero.
fmod ( x, &plusmn;&infin; ) returns x for x not infinite.

SEE ALSO

frexp, modf

STANDARDS

The fmod functions conform to ISO/IEC 9899:1999(E).