DESI-UR / VAST

Void Analysis Software Toolkit
https://vast.readthedocs.io/en/latest/
BSD 3-Clause "New" or "Revised" License
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Common Grid Origin #95

Open hbrincon opened 1 year ago

hbrincon commented 1 year ago

Due to the sensitivity of VoidFinder to the choice of grid origin, it would be good to fix the origin to [0,0,0] for all void-finding (as discussed in UofR cosmology meetings).

Right now, changing the grid origin for SDSS DR7 from the minimum galaxy coordinates to [0,0,0] results in a negative buffer length calculated in _voidfinder.py. This stems from line 412, box = coords_max - grid_origin, which creates an array with negative elements and propagates into the buffer calculation.

If we want to enforce a common grid origin, one quick solution might be to assign the grid origin as the floor of the grid_origin user input, which should snap the grid to be aligned with [0,0,0]. Otherwise, we should find a working method to account for the sensitivity of VoidFinder to the grid.