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);

       Link with -lm.

DESCRIPTION
       These functions project 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.

VERSIONS
       These functions first appeared in glibc in version 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 |
       +----------------------------+---------------+---------+
CONFORMING TO
       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)

COLOPHON
       This page is part of release 4.16 of the Linux  man-pages  project.   A
       description  of  the project, information about reporting bugs, and the
       latest    version    of    this    page,    can     be     found     at
       https://www.kernel.org/doc/man-pages/.



                                  2015-04-19                          CPROJ(3)