cproj(3) mojave man page | unix.com

CPROJ(3)						   BSD Library Functions Manual 						  CPROJ(3)

NAME
     cproj -- projection onto the Riemann sphere

SYNOPSIS
     #include <complex.h>

     double complex
     cproj(double complex z);

     long double complex
     cprojl(long double complex z);

     float complex
     cprojf(float complex z);

DESCRIPTION
     cproj(z) computes the projection of a complex floating-point number z onto the Riemann sphere: for any finite z, cproj(z) = z, but all com-
     plex infinities (including infinities with one NaN part) project to positive infinity on the real axis.

     Specifically, if z = x + iy has an infinite part (one of x or y is infinity), then cproj(z) is equivalent to INFINITY + I*copy-
     sign(0.0,cimag(z)).

NOTE
     cproj() projects onto the C99 "Riemann Sphere", which may not agree with the mathematical notion of the Riemann Sphere; in particular, it has
     two infinites (inf +- 0i) and four zeroes (+-0 +- 0i).

SEE ALSO
     complex(3)

STANDARDS
     The cproj() function conforms to ISO/IEC 9899:2011.

4th Berkeley Distribution					 December 11, 2006					 4th Berkeley Distribution