fmod, fmodf, fmodl  floatingpoint 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 floatingpoint 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 floatingpoint exception (FE_INVALID) is
raised.
y
is zeroerrno
is set to EDOM. An invalid
floatingpoint 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  MTSafe 
C99, POSIX.12001, POSIX.12008.
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)
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