xref: /netbsd-src/lib/libm/man/fmod.3 (revision dc306354b0b29af51801a7632f1e95265a68cd81)
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32.\"     from: @(#)fmod.3	5.1 (Berkeley) 5/2/91
33.\"	$NetBSD: fmod.3,v 1.6 1998/02/05 18:52:04 perry Exp $
34.\"
35.Dd May 2, 1991
36.Dt FMOD 3
37.Os
38.Sh NAME
39.Nm fmod
40.Nd floating-point remainder function
41.Sh LIBRARY
42.Lb libm
43.Sh SYNOPSIS
44.Fd #include <math.h>
45.Ft double
46.Fn fmod "double x" "double y"
47.Ft float
48.Fn fmodf "float x" "float y"
49.Sh DESCRIPTION
50The
51.Fn fmod
52function computes the floating-point remainder of
53.Fa x Ns / Fa y .
54.Sh RETURN VALUES
55The
56.Fn fmod
57and
58.Fn fmodf
59functions return the value
60.Sm off
61.Fa x - Em i * Fa y ,
62.Sm on
63for some integer
64.Em i
65such that, if
66.Fa y
67is non-zero, the result has the same sign as
68.Fa x
69and magnitude less than the magnitude of
70.Fa y .
71If
72.Fa y
73is zero, whether a domain error occurs or the
74.Fn fmod
75function returns zero is implementation-defined.
76.Sh SEE ALSO
77.Xr math 3
78.Sh STANDARDS
79The
80.Fn fmod
81function conforms to
82.St -ansiC .
83