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LSSTDESC / DC2-production

Configuration, production, validation specifications and tools for the DC2 Data Set.
BSD 3-Clause "New" or "Revised" License
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Implement matching limits for truth-match catalog #409

Closed yymao closed 3 years ago

yymao commented 3 years ago

This PR implements the truth matching limits (dmag < 1 and sep < 1") as described in the DC2 paper. For objects that do that have match with these limits, nearest neighbor is used as a match. A is_good_match column indicates whether the matching limits are met.

With this implementation, the majority of matching entries are identical with Javi's catalog, but there's 0.1% of matches that differ. Upon inspection, this difference is due to the different sources of magnitude --- I used the magnitude in the truth catalog, while Javi used cosmoDC2. Because the algorithm choose the closest magnitude within 1" when multiple candidates exist, the small difference in magnitude results in different matches in the faint end.

One tract of the truth-match catalog generated by this new script can be found at /global/cscratch1/sd/yymao/desc/match_dr6_wlimit for further inspection.

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Note that this PR is current made w.r.t to the u/yymao/allow-multiple-files branch to highlight the relevant change. But it should be merged in to master in the end.

yymao commented 3 years ago

Thank you @fjaviersanchez!

I'll merge this after #407 is merged.