Warning in picca_delta_extraction related to iminuit errors

[andreufont]

I was running Picca on mocks and noticed several warnings in the output error files:

cat /global/cfs/cdirs/desi/users/font/test_mock_53/picca_on_qq/v9.0.53.100.100/desi-4.124-4-prod/baseline/logs/picca_delta_extraction_lya_fitted-18605671.err
/global/common/software/desi/perlmutter/desiconda/20230111-2.1.0/conda/lib/python3.10/site-packages/iminuit/util.py:147: UserWarning: Assigned errors must be positive. Non-positive values are replaced by a heuristic.

Do we know what causes these? Are these benign? Non-positive errors look problematic...

[iprafols]

Hmmm I have never seen this before. It does indeed sound potentially problematic. We should check which are the offending forest(s) so that we can verify what is happening

[Waelthus]

was the root for this found by now?

[andreufont]

No idea, I haven't used Picca since. Not sure others ever found this error, but it is possible that not everyone checks for error messages...