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man:fmodf

FMOD(3) Linux Programmer's Manual FMOD(3)

NAME

`     fmod, fmodf, fmodl - floating-point remainder function`

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);```
`     Link with -lm.`
` Feature Test Macro Requirements for glibc (see feature_test_macros(7)):`
```     fmodf(), fmodl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE```

DESCRIPTION

```     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.```

RETURN VALUE

```     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.`

ERRORS

```     See  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.```

ATTRIBUTES

```     For  an  explanation  of  the  terms  used   in   this   section,   see
attributes(7).```
```     allbox;  lbw24  lb  lb  l  l  l.   Interface Attribute Value T{ fmod(),
fmodf(), fmodl() T}   Thread safety  MT-Safe```

CONFORMING TO

`     C99, POSIX.1-2001, POSIX.1-2008.`
`     The variant returning double also conforms to SVr4, 4.3BSD, C89.`

BUGS

```     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 4.16 of the Linux man-pages project.  A
`                                2017-09-15                           FMOD(3)`