add support for non-circular DS9 region files

[KshitijT]

I am using Crystalball and running into this error:

Traceback (most recent call last):
  File "/usr/local/bin/crystalball", line 7, in <module>
    pkg.main([a for a in sys.argv[1:]])
  File "/usr/local/lib/python2.7/dist-packages/Crystalball/main.py", line 10, in main
    predictor.predict( p.parse_args() )
  File "/usr/local/lib/python2.7/dist-packages/Crystalball/crystalball.py", line 172, in predict
    num=args.num_sources or None)
  File "/usr/local/lib/python2.7/dist-packages/Crystalball/wsclean.py", line 88, in import_from_wsclean
    raise ValueError('Only circular DS( regions supported for now')
ValueError: Only circular DS( regions supported for now

While I am happy to make Circular region files, it might not be the best thing to do since radio sources are not guaranteed to be circular.

[paoloserra]

pinging @o-smirnov

[o-smirnov]

Yeah sorry, this is a limitation that needs to be either fixed or documented in the help clearly.

It should have been very simple. I just read the regions files with the pyregions package (here: https://github.com/paoloserra/crystalball/blob/master/Crystalball/crystalball.py#L156), then I should be able to use the region.contains() method to determine whether each component is inside a region. However, contains() was broken as of March (see comment here: https://github.com/paoloserra/crystalball/blob/master/Crystalball/wsclean.py#L82). So as a workaround, I kludged in a check to look at region centres, and pick components within a radius of that.

I see pyregion is under active development so perhaps the earlier bug has been fixed. @KshitijT if you want to help yourself, feel free to give it a try, if it works, the code should be dead simple. And if it doesn't, we just revert to my kludge and add a note to the help. Or adopt @bennahugo's solution for determining regions...

[KshitijT]

@o-smirnov , I'll give it a shot.

Or adopt @bennahugo's solution for determining regions...

Do you mean CatDagger? I am not skilled enough to catch make regions with it which are not for dE calibration tagging..

[o-smirnov]

He had some fancy code for determining whether a source is inside a region. But that's bringing tactical nuclear warheads to a pillow fight in this case.

It should be as easy as include = any([reg.contains(coord) for reg in include_regions]), if contains() works properly now.

[o-smirnov]

The region list is read here, you shouldn't need to mess with that, it should read any ds9 file.

It's then passed (as a list called include_regions) to import_from_wsclean. So all you need to do is to fix the condiitonal here: https://github.com/paoloserra/crystalball/blob/master/Crystalball/wsclean.py#L80

[bennahugo]

Fancy code... hehe its called a dot product :) Anyway my solution will work for arbitrary shaped convex hulls

…

On Mon, 09 Sep 2019, 10:28 Kshitij Thorat, ***@***.***> wrote: @o-smirnov <https://github.com/o-smirnov> , I'll give it a shot. Or adopt @bennahugo <https://github.com/bennahugo>'s solution for determining regions... Do you mean CatDagger? I am not skilled enough to catch make regions with it which are *not* for dE calibration tagging.. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#17>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AB4RE6SR5AI2HSGZBGUIMRLQIYCLFANCNFSM4IUT4ASA> .

[bennahugo]

https://github.com/ratt-ru/CubiCal/blob/master/cubical/data_handler/geometry.py#L333

[ktrehaeven]

Hi. Can I just ask if support for non-circular regions is actually available?