Determines whether its argument has a finite value (zero, subnormal, or normal).

[Classification]

Mathematical library

[Syntax]

#include <math.h>

int isfinite(real-floating x); (C99)

[Return value]

If the argument is finite (0, subnormal number, or normal number), a value other than 0 is returned.

If the argument is infinite or NaN, 0 is returned.

[Description]

This macro determines whether its argument has a finite value (zero, subnormal, or normal).

If a type other than the floating-point type is passed to the argument, correct operation is not guaranteed.