[evla-sw-discuss] Telcal -> antsol -> cpslss

[Ken Sowinski]

> The routine at the bottom of the current antsol is called cpslss.  It
> takes a set of complex values, one per baseline, and solves for the
> response of each antenna, in both amplitude and phase.  This routine
> has an amusing history.  It was originally written in Sail by Larry
> D'Addario for the Dec 10 data reduction system.  I (or I think it was I)
> translated it into Fortran for the Modcomp version of telcal, and Ken
> Sowinski translated it into C for the interim telcal.  In the process,
> almost all comments have been lost, if they were ever there in the first
> place.  And it is a rather obscure program.  It is an iterative
> solution, because the problem becomes non-linear in the low signal-to-
> noise case.

My memory of it is more complicated than Barry's.  Larry's sail version
was handed off to Geof Cruse when he was at Pentiction where it was
recast into some structured Fortran.  I got that copy (the Sail version
could not be found at that time) and recast it into Fortran 77 for the
Modcomps.  It is that version which I transcribed into C for telcal.
Java will make five.  The comments in the first copy I saw were minimal;
I maintained that philosophy.

Ken