NAME¶
isinf, isnan, finite - test for infinity or not-a-number (NaN)
SYNOPSIS¶
#include <math.h>
int isinf(double value);
int isnan(double value);
int finite(double value);
DESCRIPTION¶
The
isinf() function returns -1 if
value represents negative
infinity, 1 if
value represents positive infinity, and 0 otherwise.
The
isnan() function returns a non-zero value if
value is
"not-a-number" (NaN), and 0 otherwise.
The
finite() function returns a non-zero value if
value is neither
infinite nor a "not-a-number" (NaN) value, and 0 otherwise.
BSD 4.3