FPCLASSIFY(3) BSD Library Functions Manual FPCLASSIFY(3)NAMEfpclassify — classify real floating type
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <math.h>
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 con‐
verted 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 ALSOisfinite(3), isnormal(3), math(3), signbit(3)STANDARDS
The fpclassify() macro conforms to ISO/IEC 9899:1999 (“ISO C99”).
BSD January 14, 2004 BSD