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);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
These functions compute the floating-point remainder of dividing
y. The return value is
n is the quotient of
rounded toward zero to an integer.
On success, these functions return the value
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 is a NaN, a NaN is returned.
x is an infinity, a domain error occurs, and a NaN is
y is zero, a domain error occurs, and a NaN is
x is +0 (-0), and
y is not zero, +0 (-0) is
See math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
xis an infinity
errno is set to EDOM (but see BUGS). An
invalid floating-point exception (FE_INVALID) is
errno is set to EDOM. An invalid
floating-point exception (FE_INVALID) is raised.
C99, POSIX.1-2001, POSIX.1-2008.
The variant returning
double also conforms to SVr4, 4.3BSD,
Before version 2.10, the glibc implementation did not set
errno to EDOM when a domain error occurred for
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