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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

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     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)