xref: /openbsd/lib/libc/gen/isgreater.3 (revision fe8883f0)
1.\"	$OpenBSD: isgreater.3,v 1.4 2017/08/29 15:03:37 millert Exp $
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3.\" Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
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27.\" $FreeBSD: src/lib/libc/gen/isgreater.3,v 1.3 2005/02/06 03:23:31 das Exp $
28.\"
29.Dd $Mdocdate: August 29 2017 $
30.Dt ISGREATER 3
31.Os
32.Sh NAME
33.Nm isgreater ,
34.Nm isgreaterequal ,
35.Nm isless ,
36.Nm islessequal ,
37.Nm islessgreater ,
38.Nm isunordered
39.Nd compare two floating-point numbers
40.Sh SYNOPSIS
41.In math.h
42.Ft int
43.Fn isgreater "real-floating x" "real-floating y"
44.Ft int
45.Fn isgreaterequal "real-floating x" "real-floating y"
46.Ft int
47.Fn isless "real-floating x" "real-floating y"
48.Ft int
49.Fn islessequal "real-floating x" "real-floating y"
50.Ft int
51.Fn islessgreater "real-floating x" "real-floating y"
52.Ft int
53.Fn isunordered "real-floating x" "real-floating y"
54.Sh DESCRIPTION
55Each of the macros
56.Fn isgreater ,
57.Fn isgreaterequal ,
58.Fn isless ,
59.Fn islessequal ,
60and
61.Fn islessgreater
62take arguments
63.Fa x
64and
65.Fa y
66and return a non-zero value if and only if its nominal
67relation on
68.Fa x
69and
70.Fa y
71is true.
72These macros always return zero if either
73argument is not a number (NaN), but unlike the corresponding C
74operators, they never raise a floating point exception.
75.Pp
76The
77.Fn isunordered
78macro takes arguments
79.Fa x
80and
81.Fa y
82and returns non-zero if at least one of the arguments is NaN.
83For any pair of floating-point values, one
84of the relationships (less, greater, equal, unordered) holds.
85.Sh SEE ALSO
86.Xr fpclassify 3
87.Sh STANDARDS
88The
89.Fn isgreater ,
90.Fn isgreaterequal ,
91.Fn isless ,
92.Fn islessequal ,
93.Fn islessgreater ,
94and
95.Fn isunordered
96macros conform to
97.St -isoC-99 .
98.Sh HISTORY
99The relational macros described above first appeared in
100.Ox 4.4 .
101