_fpclass, _fpclassf
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Returns a value indicating the floating-point classification of the argument.
int _fpclass( double x ); int _fpclassf( float x ); /* x64 only */
Parameters
x
The floating-point value to test.
The _fpclass and _fpclassf functions return an integer value that indicates the floating-point classification of the argument x. The classification may have one of the following values, defined in <float.h>.
| Value | Description |
|---|---|
_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) |
The _fpclass and _fpclassf functions are Microsoft specific. They are similar to fpclassify, but return more detailed information about the argument. The _fpclassf function is only available when compiled for the x64 platform.
| Function | Required header |
|---|---|
_fpclass | <float.h> |
For more compatibility and conformance information, see Compatibility.