fmod, fmodf, fmodl - floating-point remainder function
#include <math.h>
double fmod(double x, double y);
float fmodf(float x, float y);
long double fmodl(long double x, long double y);
Link with -lm
.
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
These 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 toward zero to an integer.
On success, these functions return the value x
- n
*y
, for some integer n
, such that the returned value has the same sign as x
and a magnitude less than the magnitude of y
.
If x
or y
is a NaN, a NaN is returned.
If x
is an infinity, a domain error occurs, and a NaN is returned.
If y
is zero, a domain error occurs, and a NaN is returned.
If x
is +0 (-0), and y
is not zero, +0 (-0) is returned.
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
x
is an infinityerrno
is set to EDOM (but see BUGS). An invalid floating-point exception (FE_INVALID) is raised.
y
is zeroerrno
is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.
For an explanation of the terms used in this section, see attributes(7).
Interface | Attribute | Value |
fmod(), fmodf(), fmodl() | Thread safety | MT-Safe |
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning double
also conforms to SVr4, 4.3BSD, C89.
Before version 2.10, the glibc implementation did not set errno
to EDOM when a domain error occurred for an infinite x
.
remainder(3)
This page is part of release 4.15 of the Linux man-pages
project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.