Generic module to include baryonic effects

[sambit-giri]

This pull request contains a custom class (BaryonCustom) to add baryonic effects from any framework. This class takes the suppression or boost data and creates an interpolator.

[damonge]

With many apologies for the delay, here's a review.

In addition to the comments below, flake8 is currently failing.

[coveralls]

Coverage Report for CI Build 24191658979

Coverage decreased (-0.4%) to 97.061%

Details

• Coverage decreased (-0.4%) from the base build.
• Patch coverage: 29 uncovered changes across 1 file (13 of 42 lines covered, 30.95%).
• No coverage regressions found.

Uncovered Changes

File	Changed	Covered	%
pyccl/baryons/baryons_custom.py	41	12	29.27%

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	6838
Covered Lines:	6637
Line Coverage:	97.06%
Coverage Strength:	4.85 hits per line

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💛 - Coveralls

[sambit-giri]

Apologies for the delayed response! I've addressed all the review comments:

• Fixed the boost_data docstring to specify the expected array shape and axis ordering.
• Fixed the update_parameters docstring to list the correct parameters.
• Simplified the array-dimension logic in boost_factor using the np.squeeze pattern (as in nfw.py).
• Also fixed a bug in update_parameters where the interpolator was being rebuilt using the local (potentially None) arguments instead of self.boost_data, self.k_data, and self.a_data.

Please let me know if anything else needs changing.

[damonge]

@sambit-giri looks great! Could we add one unit test to check that this is doing the right thing?
You can see a few examples here: https://github.com/LSSTDESC/CCL/blob/master/pyccl/tests/test_baryons_vd19.py

In this case this could be extremely simple (just checking that you recover the arrays you put in when you query the boost factor, for example).