fmod (3) - Linux Man Pages
fmod: floating-point remainder function
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)):
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
DESCRIPTIONThese 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.
RETURN VALUEOn 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.
ERRORSSee math_error(7) for information on how to determine whether an error has occurred when calling these functions.
The following errors can occur:
- Domain error: x is an infinity
- errno is set to EDOM (but see BUGS). An invalid floating-point exception (FE_INVALID) is raised.
- Domain error: y is zero
- errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7).
|fmod(), fmodf(), fmodl()||Thread safety||MT-Safe|
CONFORMING TOC99, POSIX.1-2001, POSIX.1-2008.
BUGSBefore version 2.10, the glibc implementation did not set errno to EDOM when a domain error occurred for an infinite x.
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