cproj(3) Library Functions Manual cproj(3)
NAME
cproj, cprojf, cprojl - project into Riemann Sphere
LIBRARY
Math library (libm, -lm)
SYNOPSIS
#include <complex.h>
double complex cproj(double complex z);
float complex cprojf(float complex z);
long double complex cprojl(long double complex z);
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.
ATTRIBUTES
For an explanation of the terms used in this section, see attrib-
utes(7).
┌───────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├───────────────────────────────────────────┼───────────────┼─────────┤
│ cproj(), cprojf(), cprojl() │ Thread safety │ MT-Safe │
└───────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
C11, POSIX.1-2008.
HISTORY
glibc 2.1. C99, POSIX.1-2001.
In glibc 2.11 and earlier, the implementation does something different
(a stereographic projection onto a Riemann Sphere).
SEE ALSO
cabs(3), complex(7)
Linux man-pages 6.7 2023-10-31 cproj(3)
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