NAME
fpclassify
- classify real floating type
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
int
fpclassify(
real-floating x
)
DESCRIPTION
The
fpclassify(
)
macro performs classification of its argument
x
.
An argument represented in a format wider than its semantic type is
converted to its semantic type first.
The classification is then based on the type of the argument.
IEEE 754
FP_INFINITE
-
infinity, either positive or negative
FP_NAN
-
not-a-number
(``NaN'')
FP_NORMAL
-
normal
FP_SUBNORMAL
-
subnormal
FP_ZERO
-
zero
VAX
FP_ROP
-
reserved operand
(``ROP'')
FP_DIRTYZERO
-
dirty zero
FP_NORMAL
-
finite
FP_ZERO
-
true zero
RETURN VALUES
The
fpclassify(
)
macro returns the value of the number classification macro appropriate
to its argument
x
as described above.
ERRORS
No errors are defined.
SEE ALSO
isfinite(3),
isnormal(3),
math(3),
signbit(3)
STANDARDS
The
fpclassify(
)
macro conforms to
ISO/IEC 9899:1999 (``ISO C99'') .