astropy-healpix
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Add overlap option for cone search
In Gammapy we currently call healpy.query_disc with both the inclusive=True
and the inclusive=False
option (see https://github.com/gammapy/gammapy/pull/1167#issuecomment-337156775).
As discussed in https://github.com/astropy/astropy-healpix/issues/41 , probably we don't want to spend the time to fully implement healpy.query_disc
concerning the inclusive=False
behaviour.
But maybe we could add an option to HEALPix.cone_search_lonlat that corresponds to the inclusive=True
behaviour, i.e. restricts the pixels to the ones where the center is in the cone?
@astrofrog - OK to add this?
How about calling it overlap={'center', 'full'}
which is maybe a bit more intuitive than inclusive = {True, False}
and also more extensible should we want to add other options in the future?
Concerning implementation: should it just be done at the end of the function in an if overlap == 'center'
block using a Numpy expression, subsetting with a mask that's true if the pixel center is in the cone? Or would you suggest this be added in the C or Cython code somehow?