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.

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

       C11, POSIX.1-2008.

HISTORY

       glibc 2.1.  C99, POSIX.1-2001.

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

SEE ALSO

       cabs(3), complex(7)