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islessequal(3p) - phpMan islessequal(3p) - phpMan

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```ISLESSEQUAL(3P)            POSIX Programmer's Manual           ISLESSEQUAL(3P)

PROLOG
This manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may dif-
fer (consult the corresponding Linux manual page for details of Linux behavior), or the interface  may  not  be
implemented on Linux.

NAME
islessequal - test if x is less than or equal to y

SYNOPSIS
#include <math.h>

int islessequal(real-floating x, real-floating y);

DESCRIPTION
The  islessequal()  macro  shall determine whether its first argument is less than or equal to its second argu-
ment. The value of islessequal( x, y) shall be equal to (x) <= (y); however, unlike (x) <= (y), islessequal( x,
y) shall not raise the invalid floating-point exception when x and y are unordered.

RETURN VALUE
Upon successful completion, the islessequal() macro shall return the value of (x) <= (y).

If x or y is NaN, 0 shall be returned.

ERRORS
No errors are defined.

The following sections are informative.

EXAMPLES
None.

APPLICATION USAGE
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.  Rela-
tional  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-floating  indi-
cates that the argument shall be an expression of real-floating type.

RATIONALE
None.

FUTURE DIRECTIONS
None.

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