HP-UX Reference (11i v1 05/09) - 3 Library Functions A-M (vol 6)

i
isunordered(3M) isunordered(3M)
NAME
isunordered( ) - floating-point comparison macro (unordered)
SYNOPSIS
#include <math.h>
int isunordered(
floating-expr x, floating-expr
y);
DESCRIPTION
The isunordered()
macro determines whether its arguments are unordered. The arguments are unor-
dered if at least one argument is a NaN.
The macro can be used with either
double
or float arguments.
The ISO/ANSI C committee has approved the
isunordered()
macro for inclusion in the C9X draft
standard.
To use the
isunordered()
macro, compile either with the default -Ae
option or with the -Aa and
-D_HPUX_SOURCE
options. Make sure your program includes <math.h>. Link in the math library by
specifying
-lm on the compiler or linker command line.
RETURN VALUE
The isunordered() macro returns 1 if its arguments are unordered (that is, if either argument is a
NaN) and 0 otherwise.
ERRORS
No errors are defined.
SEE ALSO
isgreater(3M), isgreaterequal(3M), isless(3M), islessequal(3M), islessgreater(3M), math(5).
HP-UX 11i Version 1: September 2005 − 1 − Hewlett-Packard Company Section 3−−511