xref: /netbsd/lib/libm/man/fmod.3 (revision bf9ec67e)
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32.\"     from: @(#)fmod.3	5.1 (Berkeley) 5/2/91
33.\"	$NetBSD: fmod.3,v 1.9 2002/02/07 07:00:49 ross Exp $
34.\"
35.Dd May 2, 1991
36.Dt FMOD 3
37.Os
38.Sh NAME
39.Nm fmod ,
40.Nm fmodf
41.Nd floating-point remainder function
42.Sh LIBRARY
43.Lb libm
44.Sh SYNOPSIS
45.Fd #include \*[Lt]math.h\*[Gt]
46.Ft double
47.Fn fmod "double x" "double y"
48.Ft float
49.Fn fmodf "float x" "float y"
50.Sh DESCRIPTION
51The
52.Fn fmod
53function computes the floating-point remainder of
54.Fa x Ns / Fa y .
55.Sh RETURN VALUES
56The
57.Fn fmod
58and
59.Fn fmodf
60functions return the value
61.Sm off
62.Fa x - Em i * Fa y ,
63.Sm on
64for some integer
65.Em i
66such that, if
67.Fa y
68is non-zero, the result has the same sign as
69.Fa x
70and magnitude less than the magnitude of
71.Fa y .
72If
73.Fa y
74is zero, whether a domain error occurs or the
75.Fn fmod
76function returns zero is implementation-defined.
77.Sh SEE ALSO
78.Xr math 3
79.Sh STANDARDS
80The
81.Fn fmod
82function conforms to
83.St -ansiC .
84