1CPROJ(3)                   Linux Programmer's Manual                  CPROJ(3)
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NAME

6       cproj, cprojf, cprojl - project into Riemann Sphere
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SYNOPSIS

9       #include <complex.h>
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11       double complex cproj(double complex z);
12       float complex cprojf(float complex z);
13       long double complex cprojl(long double complex z);
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15       Link with -lm.
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DESCRIPTION

18       These functions project a point in the plane onto the surface of a Rie‐
19       mann Sphere, the one-point compactification of the complex plane.  Each
20       finite  point  z projects to z itself.  Every complex infinite value is
21       projected to a single infinite value, namely to  positive  infinity  on
22       the real axis.
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VERSIONS

25       These functions first appeared in glibc in version 2.1.
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ATTRIBUTES

28       For  an  explanation  of  the  terms  used  in  this  section,  see at‐
29       tributes(7).
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31       ┌────────────────────────────────────────────┬───────────────┬─────────┐
32       │Interface                                   │ Attribute     │ Value   │
33       ├────────────────────────────────────────────┼───────────────┼─────────┤
34       │cproj(), cprojf(), cprojl()                 │ Thread safety │ MT-Safe │
35       └────────────────────────────────────────────┴───────────────┴─────────┘
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CONFORMING TO

38       C99, POSIX.1-2001, POSIX.1-2008.
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NOTES

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

45       cabs(3), complex(7)
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COLOPHON

48       This  page  is  part of release 5.13 of the Linux man-pages project.  A
49       description of the project, information about reporting bugs,  and  the
50       latest     version     of     this    page,    can    be    found    at
51       https://www.kernel.org/doc/man-pages/.
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55                                  2021-03-22                          CPROJ(3)