Tests for infinity.
#include <math.h> int isinf (x) real-floating x;
The isinf macro determines whether its argument value is an infinity (positive or negative). An argument represented in a format wider than its semantic type is converted to its semantic type. Determination is based on the type of the argument.
| x | Specifies the value to be checked. |
The isinf macro returns a nonzero value if its argument has an infinite value.
fpclassify Macro, isfinite Macro, class, _class, finite, isnan, or unordered Subroutines, isnormal Macro.
The signbit Subroutine in AIX 5L Version 5.2 Technical Reference: Base Operating System and Extensions Volume 2.
math.h in AIX 5L Version 5.2 Files Reference.