xref: /freebsd/lib/msun/man/fmod.3 (revision dc36d6f9bb1753f3808552f3afd30eda9a7b206a)

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.Dd April 3, 2022
.Dt FMOD 3
.Os
.Sh NAME
.Nm fmod ,
.Nm fmodf ,
.Nm fmodl
.Nd floating-point remainder functions
.Sh LIBRARY
.Lb libm
.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 ,
.Fn fmodf ,
and
.Fn fmodl
functions compute the floating-point remainder of
.Fa x Ns / Fa y .
.Sh RETURN VALUES
If
.Fa y
is non-zero, 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 the result has the same sign as
.Fa x
and magnitude less than the magnitude of
.Fa y .
If
.Fa y
is zero, a \*(Na is produced.
.Sh SEE ALSO
.Xr math 3
.Sh STANDARDS
The
.Fn fmod ,
.Fn fmodf ,
and
.Fn fmodl
functions conform to
.St -isoC-99 .
.Sh HISTORY
An
.Fn fmod
function first appeared in
.At v5 .