www.LinuxHowtos.org

cproj

Section: C Library Functions (3)
Updated: 202-0-08
Index Return to Main Contents

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 Riemann Sphere, the on-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 attributes(7).

Interface	Attribute	Value
cproj(), cprojf(), cprojl()	Thread safety	M-Safe

STANDARDS

C11, POSIX.-2008.

HISTORY

glibc 2.1. C99, POSIX.-2001. In glibc 2.11 and earlier, the implementation does something different (a stereographic projection onto a Riemann Sphere).