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Test Your Knowledge in Computers #330
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isgreaterequal(3) [linux man page]

```ISGREATER(3)						     Linux Programmer's Manual						      ISGREATER(3)

NAME
isgreater, isgreaterequal, isless, islessequal, islessgreater, isunordered - floating-point relational tests without exception for NaN

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);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

All functions described here:
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99

DESCRIPTION
The  normal  relation  operations  (like  <, "less than") will fail if one of the operands is NaN.  This will cause an exception.  To avoid
this, C99 defines these macros.	The macros are guaranteed to evaluate their operands only once.  The operands can be of any real floating-
point 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()
determines whether its arguments are unordered, that is, whether at least one of the arguments is a NaN.

RETURN VALUE
The macros other than isunordered() return the result of the relational comparison; these macros return 0 if either argument is a NaN.

isunordered() returns 1 if x or y is NaN and 0 otherwise.

ERRORS
No errors occur.

CONFORMING TO
C99, POSIX.1-2001.

NOTES
Not all hardware supports these functions, and where hardware support isn't provided, they will be emulated by macros.  This will result in
a performance penalty.  Don't use these functions if NaN is of no concern for you.

fpclassify(3), isnan(3)

COLOPHON
This  page is part of release 3.27 of the Linux man-pages project.  A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.

2010-09-20							      ISGREATER(3)```

Check Out this Related Man Page

```ISGREATER(3)						     Linux Programmer's Manual						      ISGREATER(3)

NAME
isgreater, isgreaterequal, isless, islessequal, islessgreater, isunordered - floating-point relational tests without exception for NaN

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);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

All functions described here:
_XOPEN_SOURCE >= 600 || _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
or cc -std=c99

DESCRIPTION
The  normal  relation  operations  (like  <, "less than") will fail if one of the operands is NaN.  This will cause an exception.  To avoid
this, C99 defines these macros.	The macros are guaranteed to evaluate their operands only once.  The operands can be of any real floating-
point 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()
determines whether its arguments are unordered, that is, whether at least one of the arguments is a NaN.

RETURN VALUE
The macros other than isunordered() return the result of the relational comparison; these macros return 0 if either argument is a NaN.

isunordered() returns 1 if x or y is NaN and 0 otherwise.

ERRORS
No errors occur.

CONFORMING TO
C99, POSIX.1-2001.

NOTES
Not all hardware supports these functions, and where hardware support isn't provided, they will be emulated by macros.  This will result in
a performance penalty.  Don't use these functions if NaN is of no concern for you.