CPROJ(3P)                  POSIX Programmer's Manual                 CPROJ(3P)



NAME
       cproj, cprojf, cprojl - complex projection functions

SYNOPSIS
       #include <complex.h>

       double cproj(double complex z);
       float cprojf(float complex z);
       long double cprojl(long double complex z);


DESCRIPTION
       These  functions  compute  a projection of z onto the Riemann sphere: z
       projects to z , except that all complex infinities (even those with one
       infinite  part  and  one  NaN part) project to positive infinity on the
       real axis. If z has an infinite part, then cproj(z) shall be equivalent
       to: INFINITY + I * copysign(0.0, cimag(z))

RETURN VALUE
       These  functions  return  the  value of the projection onto the Riemann
       sphere.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       carg(),  cimag(),  conj(),  creal()  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, <complex.h>

COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE and
       The  Open Group Standard, the original IEEE and The Open Group Standard
       is the referee document. The original Standard can be  obtained  online
       at http://www.opengroup.org/unix/online.html .



IEEE/The Open Group                  2003                            CPROJ(3P)