Returns status word containing information on floating-point class.
int _fpclass( double
x );
| Function | Required Header | Compatibility |
| _fpclass | <float.h> | Win 95, Win NT |
For additional compatibility information, see Compatibility in the Introduction.
Libraries
| LIBC.LIB | Single thread static library, retail version |
| LIBCMT.LIB | Multithread static library, retail version |
| MSVCRT.LIB | Import library for MSVCRT.DLL, retail version |
Return Value
_fpclass returns an integer value that indicates the floating-point class of its argument x. The status word may have one of the following values, defined in FLOAT.H.
| Value | Meaning |
| _FPCLASS_SNAN | Signaling NaN |
| _FPCLASS_QNAN | Quiet NaN |
| _FPCLASS_NINF | Negative infinity ( –INF) |
| _FPCLASS_NN | Negative normalized non-zero |
| _FPCLASS_ND | Negative denormalized |
| _FPCLASS_NZ | Negative zero ( – 0) |
| _FPCLASS_PZ | Positive 0 (+0) |
| _FPCLASS_PD | Positive denormalized |
| _FPCLASS_PN | Positive normalized non-zero |
| _FPCLASS_PINF | Positive infinity (+INF) |
Parameter
x
Double-precision floating-point value
Floating-Point Support Routines
See Also _isnan