1.\" Copyright (c) 2003 David Schultz <das@FreeBSD.org> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 13.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 17.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23.\" SUCH DAMAGE. 24.\" 25.\" $FreeBSD$ 26.\" 27.Dd February 12, 2003 28.Dt ISGREATER 3 29.Os 30.Sh NAME 31.Nm isgreater , isgreaterequal , isless , islessequal , 32.Nm islessgreater , isunordered 33.Nd "compare two floating-point numbers" 34.Sh LIBRARY 35.Lb libc 36.Sh SYNOPSIS 37.In math.h 38.Ft int 39.Fn isgreater "real-floating x" "real-floating y" 40.Ft int 41.Fn isgreaterequal "real-floating x" "real-floating y" 42.Ft int 43.Fn isless "real-floating x" "real-floating y" 44.Ft int 45.Fn islessequal "real-floating x" "real-floating y" 46.Ft int 47.Fn islessgreater "real-floating x" "real-floating y" 48.Ft int 49.Fn isunordered "real-floating x" "real-floating y" 50.Sh DESCRIPTION 51Each of the macros 52.Fn isgreater , 53.Fn isgreaterequal , 54.Fn isless , 55.Fn islessequal , 56and 57.Fn islessgreater 58take arguments 59.Fa x 60and 61.Fa y 62and return a non-zero value if and only if its nominal 63relation on 64.Fa x 65and 66.Fa y 67is true. 68These macros always return zero if either 69argument is not a number (NaN), but unlike the corresponding C 70operators, they never raise a floating point exception. 71.Pp 72The 73.Fn isunordered 74macro takes arguments 75.Fa x 76and 77.Fa y 78and returns non-zero if and only if any of 79.Fa x 80or 81.Fa y 82are NaNs. 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.Xr math 3 , 88.Xr signbit 3 89.Sh STANDARDS 90The 91.Fn isgreater , 92.Fn isgreaterequal , 93.Fn isless , 94.Fn islessequal , 95.Fn islessgreater , 96and 97.Fn isunordered 98macros conform to 99.St -isoC-99 . 100.Sh HISTORY 101The relational macros described above first appeared in 102.Fx 5.1 . 103