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.

CONFORMING TO

       BSD 4.3

GNU                                               June 2, 1993                                          ISINF(3)