Index for Section 3

Alphabetical listing for F

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fmod(3)
NAME
  fmod, drem, remainder - Compute the floating-point remainder

SYNOPSIS
  #include <math.h>

  double fmod(
	  double x,
	  double y );

  float fmodf(
	  float x,
	  float y );

  long double fmodl(
	  long double x,
	  long double y );

  double drem(
	  double x,
	  double y );

  float dremf(
	  float x,
	  float y );

  long double dreml(
	  long double x,
	  long double y );

  double remainder(
	  double x,
	  double y );

  float remainderf(
	  float x,
	  float y );

  long double remainderl(
	  long double x,
	  long double y );

LIBRARY
  Math Library (libm)

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  fmod():  XPG4

  remainder():	XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

DESCRIPTION
  The fmod(), fmodf(), and fmodl() functions return the remainder r = x -
  n*y, where n = trunc(x/y). The result has the same sign as x and magnitude
  less than the magnitude of y. The remainder is computed exactly and |r| is
  less than |y|.

  The drem(), dremf(), dreml(), remainder(), remainderf(), and remainderl()
  functions return the remainder r = x - n*y, where n = rint(x/y).
  Additionally, if |n- x/y|=1/2, then n is even.  The remainder is computed
  exactly and |r| is less than or equal to |y|/2.

  The drem() and remainder() functions are aliases of each other. The
  dremf(), and remainderf() functions are aliases of each other. The dreml()
  and remainderl() functions are aliases of each other.

  The following table describes function behavior in response to exceptional
  arguments:

  ____________________________________________________________________
  Function					      Routine Behavior

				  Exceptional
				  Argument
  ____________________________________________________________________
				  x = infinity	      Invalid argument

  fmod(), fmodf(), fmodl()
				  y = 0		      Invalid argument

  fmod(), fmodf(), fmodl()
				  x = infinity	      Invalid argument

  drem(), dremf(), dreml()
				  y = 0		      Invalid argument

  drem(), dremf(), dreml()
  remainder()			  x = infinity	      Invalid argument
  remainderf()			  x = infinity	      Invalid argument
  remainderl()			  x = infinity	      Invalid argument
  remainder()			  y = 0		      Invalid argument
  remainderf()			  y = 0		      Invalid argument
  remainderl()			  y = 0		      Invalid argument
  ____________________________________________________________________

Index for Section 3

Alphabetical listing for F

Top of page