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.\"     from: @(#)fmod.3	5.1 (Berkeley) 5/2/91
.\"
.Dd $Mdocdate: July 17 2013 $
.Dt FMOD 3
.Os
.Sh NAME
.Nm fmod ,
.Nm fmodf ,
.Nm fmodl
.Nd floating-point remainder functions
.Sh SYNOPSIS
.In math.h
.Ft double
.Fn fmod "double x" "double y"
.Ft float
.Fn fmodf "float x" "float y"
.Ft long double
.Fn fmodl "long double x" "long double y"
.Sh DESCRIPTION
The
.Fn fmod
function computes the floating-point remainder of
.Fa x Ns / Fa y .
The
.Fn fmodf
function is a single precision version of
.Fn fmod .
The
.Fn fmodl
function is an extended precision version of
.Fn fmod .
.Sh RETURN VALUES
The
.Fn fmod ,
.Fn fmodf
and
.Fn fmodl
functions return the value
.Sm off
.Fa x - Em i * Fa y ,
.Sm on
for some integer
.Em i
such that, if
.Fa y
is non-zero, the result has the same sign as
.Fa x
and magnitude less than the magnitude of
.Fa y .
If
.Fa y
is zero, whether a domain error occurs or the
.Fn fmod
function returns zero is implementation-defined.
.Sh SEE ALSO
.Xr remainder 3
.Sh STANDARDS
The
.Fn fmod
function conforms to
.St -ansiC .
.Sh HISTORY
An
.Fn fmod
function first appeared in
.At v5 .