CPROJ(3) | Linux Programmer's Manual | CPROJ(3) |

# 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*

**);**

*-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

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

# SEE ALSO

**cabs**(3),

**complex**(7)

# COLOPHON

This page is part of release 3.53 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/.

2010-06-10 |