ISGREATER(3) Linux Programmer's Manual ISGREATER(3)
NAME
isgreater, isgreaterequal, isless, islessequal, islessgreater,
isunordered  macros to test a relation
SYNOPSIS
#include <<math.h>>
int isgreater(x,y);
int isgreaterequal(x,y);
int isless(x,y);
int islessequal(x,y);
int islessgreater(x,y);
int isunordered(x,y);
Compile with std=c99; link with lm.
DESCRIPTION
The normal relation operations (like less) will fail if one of the op
erands is NaN. This will cause an exception. To avoid this, C99
defines these macros. The macros are guaranteed to evaluate their op
erands only once. The operand can be of any real floatingpoint type.
isgreater()
determines (x) > (y) without an exception if x or y is NaN.
isgreaterequal()
determines (x) >= (y) without an exception if x or y is NaN.
isless()
determines (x) < (y) without an exception if x or y is NaN.
islessequal()
determines (x) <= (y) without an exception if x or y is NaN.
islessgreater()
determines (x) < (y)  (x) > (y) without an exception if x or y
is NaN. This macro is not equivalent to x != y because that
expression is true if x or y is NaN.
isunordered()
is true if x or y is NaN and false otherwise.
CONFORMING TO
C99.
NOTES
Not all hardware supports these functions, and where it doesn't, they
will be emulated by macros. This will give you a performance penalty.
Don't use these functions if NaN is of no concern for you.
SEE ALSO
fpclassify(3), isnan(3)
COLOPHON
This page is part of release 3.05 of the Linux manpages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/manpages/.
20020727 ISGREATER(3)
