fpclassify

Syntax

#include <math.h>

Description

The macro fpclassify returns the kind of the floating point value supplied.

Return Value

FP_INFINITE, FP_NAN, FP_NORMAL, FP_SUBNORMAL, FP_ZERO or FP_UNNORMAL.

Portability

ANSI/ISO C

C99; not C89

Example

float f = 1; double d = INFINITY; long double ld = NAN; if( fpclassify(f) != FP_NORMAL ) { printf("Something is wrong with the implementation!\n"); } if( fpclassify(d) != FP_INFINITE ) { printf("Something is wrong with the implementation!\n"); } if( fpclassify(ld) != FP_NAN ) { printf("Something is wrong with the implementation!\n"); }