xref: /netbsd/lib/libm/man/finite.3 (revision a6986041)
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28.\"     from: @(#)ieee.3	6.4 (Berkeley) 5/6/91
29.\"	$NetBSD: finite.3,v 1.2 2011/08/06 11:09:22 wiz Exp $
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31.Dd July 28, 2011
32.Dt FINITE 3
33.Os
34.Sh NAME
35.Nm finite ,
36.Nm finitef
37.Nd tests for finite values
38.Sh LIBRARY
39.Lb libm
40.Sh SYNOPSIS
41.In math.h
42.Ft int
43.Fn finite "double x"
44.Ft int
45.Fn finitef "float x"
46.Sh DESCRIPTION
47The
48.Fn finite
49function returns the value 1 when
50.Bd -ragged -offset indent
51\-\*(If \*(Lt
52.Fa x
53\*(Lt +\*(If.
54.Ed
55.Pp
56Otherwise a zero is returned
57(that is,
58.Pf \*(Ba Ns Fa x Ns \*(Ba
59= \*(If or
60.Fa x
61is \*(Na).
62.Sh SEE ALSO
63.Xr isfinite 3 ,
64.Xr math 3
65.Sh STANDARDS
66The described functions conform to
67.St -ieee754 .
68Note that unlike
69.Xr isfinite 3 ,
70neither function is present in the
71.Dv ISO
72C-language standards or in the
73.Dv IEEE
74.Dv POSIX
75standards.
76.Sh HISTORY
77The
78.Nm finite
79and
80.Fn finitef
81functions first appeared in
82.Bx 4.3 .
83