cproj, cprojf, cprojl – project into Riemann Sphere

USAGE
       #include <complex.h>

       double complex cproj(double complex z);
       float complex cprojf(float complex z);
       long double complex cprojl(long double complex z);

       Link with -lm.

DESCRIPTION
       This  function projects a point in the plane onto the surface of a Rie-
       mann Sphere, the one-point compactification of the complex plane.  Each
       finite  point  z projects to z itself.  Every complex infinite value is
       projected to a single infinite value, namely to  positive  infinity  on
       the real axis.

CONFORMING TO
       C99

NOTE
       The  glibc implementation is broken and does something entirely differ-
       ent.

SEE ALSO
       cabs(3), complex(7)