NAME

       cproj, cprojf, cprojl - project into Riemann Sphere

LIBRARY

       Math library (libm, -lm)

SYNOPSIS

       #include <complex.h>

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

DESCRIPTION

       These  functions  project  a  point in the plane onto the surface of a Riemann 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.

VERSIONS

       These functions were added in glibc 2.1.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).

       ┌───────────────────────────────────────────────────────────────┬───────────────┬─────────┐
       │Interface                                                      │ Attribute     │ Value   │
       ├───────────────────────────────────────────────────────────────┼───────────────┼─────────┤
       │cproj(), cprojf(), cprojl()                                    │ Thread safety │ MT-Safe │
       └───────────────────────────────────────────────────────────────┴───────────────┴─────────┘

STANDARDS

       C99, POSIX.1-2001, POSIX.1-2008.

NOTES

       In glibc 2.11 and earlier, the implementation does something  different  (a  stereographic
       projection onto a Riemann Sphere).

SEE ALSO

       cabs(3), complex(7)