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islessgreater - test if x is less than or greater than y

#include <math.h>

int islessgreater(real-floatingx, real-floatingy);

The

islessgreater() macro shall determine whether its first argument is less than or greater than its second argument. Theislessgreater(x,y) macro is similar to (x) < (y) || (x) > (y); however,islessgreater(x,y) shall not raise the invalid floating-point exception whenxandyare unordered (nor shall it evaluatexandytwice).

Upon successful completion, the

islessgreater() macro shall return the value of (x) < (y) || (x) > (y).If

xoryis NaN, 0 shall be returned.

No errors are defined.

The following sections are informative.

None.

The relational and equality operators support the usual mathematical relationships between numeric values. For any ordered pair of numeric values, exactly one of the relationships (less, greater, and equal) is true. Relational operators may raise the invalid floating-point exception when argument values are NaNs. For a NaN and a numeric value, or for two NaNs, just the unordered relationship is true. This macro is a quiet (non-floating-point exception raising) version of a relational operator. It facilitates writing efficient code that accounts for NaNs without suffering the invalid floating-point exception. In the SYNOPSIS section,

real-floatingindicates that the argument shall be an expression ofreal-floatingtype.

None.

None.

isgreater() ,isgreaterequal() ,isless() ,islessequal() ,isunordered() , the Base Definitions volume of IEEE Std 1003.1-2001<math.h>

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group |
ISLESSGREATER (P) | 2003 |