CLASS(3C)CLASS(3C)NAME
fpclassify, isfinite, isinf, isnan, isnormal, signbit, fpclassifyf,
isfinitef, isinff, isnanf, isnormalf, signbitf, fpclassifyl, isfinitel,
isinfl, isnanl, isnormall, signbitl,
- classification macros (and functions)
SYNOPSIS
#include <math.h>
int fpclassify(real-floating x);
int isfinite(real-floating x);
int isinf(real-floating x);
int isnan(real-floating x);
int isnormal(real-floating x);
int signbit(real-floating x);
DESCRIPTION
These macros (and functions) are not available for programs compiled with
the O32 ABI.
These macros are implemented in terms of ordinary functions depending on
the argument used; for example, if x is a float expression, the macro
fpclassify generates a call to the function fpclassifyf. If x is a
double expression, the macro generates a call to the function fpclassify.
If x is a long double expression, the macro generates a call to the
function fpclassifyl.
The fpclassify macro returns the value of the number classification macro
appropriate to the value of its argument. Possible return values are
FP_ZERO, FP_SUBNORMAL, FP_NORMAL, FP_INFINITE, and FP_NAN, whose values
are defined in math.h.
The isfinite macro returns a non-zero value if and only if its argument
has a finite value.
The isinf macro returns a nonzero value if and only if its argument has
an infinite value.
The isnan macro returns a nonzero value if and only if its argument is a
NaN (not-a-number)
The isnormal macro returns a nonzero value if and only if its argument
has a normal value according to IEEE floating point definitions.
The signbit macro returns a nonzero value if and only if the sign of its
argument value is negative.
NOTES
Long double operations on this system are only supported in round to
nearest rounding mode (the default). The system must be in round to
nearest rounding mode when calling any of the long double functions, or
incorrect answers will result.
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CLASS(3C)CLASS(3C)SEE ALSOmath(3M), frexp(3C)
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