Index for Section 3

Alphabetical listing for F

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

LIBRARY
  Math Library (libm.a)

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);

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			  Exceptional Argument	    Routine Behavior
  __________________________________________________________________________
  fmod(),  fmodf(),	fmodl()	  x = infinity		    Invalid argument
  fmod(),  fmodf(),	fmodl()	  y = 0			    Invalid argument
  drem(),  dremf(),	dreml()	  x = infinity		    Invalid argument
  drem(),  dremf(),	dreml()	  y = 0			    Invalid argument
  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