Draft: Add Power Law + Dip + Break model

[afarah18]

This merge request adds a 2-dimensional mass model to mass.py, as well as two helper functions: a 1D mass model and a pairing function. These are meant to span the whole spectrum of CBCs rather than just the BBHs.

• The 1d model, power_law_dip_break_1d is a broken powerlaw with a low pass filter at very low masses, a notch filter somewhere between NS-like and BH-like masses, and a high pass filter at high masses. The power law breaks at the upper end of the notch filter.
• The 2d model is titled power_law_dip_break where both the primary and secondary masses follow power_law_dip_break_1d with the same parameters, and primary and secondary masses are related by a pairing function that goes as the mass ratio to a power. This is the model described as Powerlaw+Dip+Break in https://arxiv.org/abs/2006.13178

[afarah18]

Hi Colm,

Thanks for your reply and for the tip about pre-commit. I just addressed your comments by editing my fork, but I'm still marking this as a draft until I can test everything thoroughly. I see the backend compatibility with gwpopulation_pipe is fixed so I can run my tests now and I'll let you know when they finish/ I can confirm things work as expected. Nevermind, they are not yet fixed, I was looking at the wrong PR. I will wait until I can pull those changes and then run my tests

Regardless, though, I'm happy to implement PDB as a separate module or package. I didn't realize that was an option with GWPopulation, but it definitely seems reasonable! Whichever is better for you is fine by me. I'm happy to help with documentation of that as well.

[codecov-commenter]

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Attention: 9 lines in your changes are missing coverage. Please review.

Comparison is base (2d43f7c) 94.93% compared to head (41e0f1f) 93.88%.

Files	Patch %	Lines
gwpopulation/models/mass.py	25.00%	9 Missing :warning:

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[ColmTalbot]

I just created a (filled-in) template repository for how to package up custom models, https://github.com/ColmTalbot/gwpopulation-additional-models.

This is still very much a WIP and will need documentation for some of the features, especially setting up the backend as a plugin.

This also currently needs a pre-release of GWPopulation.

[afarah18]

Sounds good, I'll take a look soon!

[ColmTalbot]

Closing this in favour of it living in a standalone package.