INFNAN(3) Linux Programmer's Manual INFNAN(3)
infnan - deal with infinite or not-a-number (NaN) result
#include <math.h> double infnan(int error); Link with -lm.
The infnan() function returns a suitable value for infinity and "not- a-number" (NaN) results. The value of error can be ERANGE to represent infinity or anything else to represent NaN. errno is also set.
If error is ERANGE (Infinity), HUGE_VAL is returned. If error is -ERANGE (-Infinity), -HUGE_VAL is returned. If error is anything else, NAN is returned.
EDOM The value of error is "not-a-number" (NaN). ERANGE The value of error is positive infinity or negative infinity.
This obsolete function was provided in libc4 and libc5, but is not available in glibc2.
This page is part of release 4.10 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/. GNU 1993-06-02 INFNAN(3)
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