**NAME**

cproj, cprojf, cprojl - project into Riemann Sphere

**SYNOPSIS**

**#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
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 first appeared in glibc in version 2.1.

**CONFORMING** **TO**

C99.

**NOTES**

The glibc implementation is broken and does something entirely
different.

**SEE ALSO**

**cabs**(3), **complex**(7)

**COLOPHON**

This page is part of release 3.24 of the Linux __man-pages__ project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2008-08-11 CPROJ(3)