minix/lib/libc/gen/isgreater.3

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.\" $NetBSD: isgreater.3,v 1.1 2007/02/22 22:08:20 drochner Exp $
.\"
.\" Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
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.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" FreeBSD: /repoman/r/ncvs/src/lib/libc/gen/isgreater.3,v 1.3 2005/02/06 03:23:31 das Exp
.\"
.Dd February 12, 2003
.Dt ISGREATER 3
.Os
.Sh NAME
.Nm isgreater , isgreaterequal , isless , islessequal ,
.Nm islessgreater , isunordered
.Nd "compare two floating-point numbers"
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In math.h
.Ft int
.Fn isgreater "real-floating x" "real-floating y"
.Ft int
.Fn isgreaterequal "real-floating x" "real-floating y"
.Ft int
.Fn isless "real-floating x" "real-floating y"
.Ft int
.Fn islessequal "real-floating x" "real-floating y"
.Ft int
.Fn islessgreater "real-floating x" "real-floating y"
.Ft int
.Fn isunordered "real-floating x" "real-floating y"
.Sh DESCRIPTION
Each of the macros
.Fn isgreater ,
.Fn isgreaterequal ,
.Fn isless ,
.Fn islessequal ,
and
.Fn islessgreater
take arguments
.Fa x
and
.Fa y
and return a non-zero value if and only if its nominal
relation on
.Fa x
and
.Fa y
is true.
These macros always return zero if either
argument is not a number (NaN), but unlike the corresponding C
operators, they never raise a floating point exception.
.Pp
The
.Fn isunordered
macro takes arguments
.Fa x
and
.Fa y
and returns non-zero if and only if neither
.Fa x
nor
.Fa y
are NaNs.
For any pair of floating-point values, one
of the relationships (less, greater, equal, unordered) holds.
.Sh SEE ALSO
.Xr fpclassify 3 ,
.Xr math 3 ,
.Xr signbit 3
.Sh STANDARDS
The
.Fn isgreater ,
.Fn isgreaterequal ,
.Fn isless ,
.Fn islessequal ,
.Fn islessgreater ,
and
.Fn isunordered
macros conform to
.St -isoC-99 .
.Sh HISTORY
The relational macros described above first appeared in
.Nx 5.0 .