NAME
isgreater,
isgreaterequal,
isless,
islessequal,
islessgreater,
isunordered —
compare two floating-point numbers
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <math.h>
int
isgreater(
real-floating
x,
real-floating y);
int
isgreaterequal(
real-floating
x,
real-floating y);
int
isless(
real-floating
x,
real-floating y);
int
islessequal(
real-floating
x,
real-floating y);
int
islessgreater(
real-floating
x,
real-floating y);
int
isunordered(
real-floating
x,
real-floating y);
DESCRIPTION
Each of the macros
isgreater(),
isgreaterequal(),
isless(),
islessequal(), and
islessgreater() take
arguments
x and
y and return a
non-zero value if and only if its nominal relation on
x
and
y is true. These macros always return zero if either
argument is not a number (NaN), but unlike the corresponding C operators, they
never raise a floating point exception.
The
isunordered() macro takes arguments
x and
y and returns non-zero if
and only if neither
x nor
y are
NaNs. For any pair of floating-point values, one of the relationships (less,
greater, equal, unordered) holds.
SEE ALSO
fpclassify(3),
math(3),
signbit(3)
STANDARDS
The
isgreater(),
isgreaterequal(),
isless(),
islessequal(),
islessgreater(), and
isunordered() macros
conform to
ISO/IEC 9899:1999
(“ISO C99”).
HISTORY
The relational macros described above first appeared in
NetBSD
5.0.