[Difx-users] DIFXCalc max number of antenna

[Olaf Wucknitz]

Hi Chris,

On Thu, 14 Jun 2018, Chris.Phillips at csiro.au wrote:

> I just increased the size of these parameters to 41 (looks like it is 
> #antenna + centre of earth) and can now successfully run difxcalc with 
> 36 antenna.  It now seems to run fine.
>
> I noted that it looks like max # scans is 500, which feels a little too 
> small for my liking (I guess if you run DIFX in subjobs, this is less of 
> an issue).
>
> I can push these changes back to subversion if it is thought to be a 
> reasonable increase.

increasing the numbers is a good idea. Can you maybe also add a brief 
summary of the limits that you know of in a few lines in one of the 
files (or a new one)?

I guess a higher number for the antennas would be useful. I am using 
difxcalc for experiments with LOFAR, where we can have many more 
(sub-)stations. So far I have not run in the limit, but it can easily 
happen. Maybe go for 100 (99 plus centre of Earth)?

I am aware of one more limit that I once reached:

# MAX_ARC_SRC=300   in cmxsr11.i

I used a field of many sources to test how good some polynomial (as 
function of position) approximation was. 300 is probably good enough for 
almost all purposes, just want to mention it for completeness.


Cheers,
Olaf