Sg/add pr guidelines

[skygering]

Added another set PR template and again fixed the deprecated trapz function name.

[skygering]

There are a few other test warnings I would like to fix. Within the momentum file (here and here), we are taking the square root of a negative number. This is throwing a warning and returning NaN. This is clearly expected behavior, because it is texted for within the tests. However, it isn't good practice to depend on this type of behavior (e.g. the return of a failed call). We should test if it is going to be a negative, and if so, throw a warning that is more physical (i.e. "in this scenario you can't calculate induction because") and manually set it to NaN.

I can do this, but what is the Cx that is passed into both functions?

[kirbyh]

I can do this, but what is the Cx that is passed into both functions?

The variable Cx is the axial force coefficient, which is equivalent to $C_T$ in momentum theory. It makes sense to me to check whether the value under the radical $-C_T^2 \sin^2\gamma - 16C_T + 16$ is negative and to mask with nans before continuing, and maybe to raise a more descriptive warning. This value (and also the simpler $1-C_T$ in classical momentum theory) will be negative at high thrust (in no yaw: $C_T > 1$), where the UMM or other empirical high-thrust corrections are needed to resolve the BEM solution. If there is a standard way to put this in a warning (and to be able to toggle the warnings on/off), that would be useful

[iupfal]

Great idea, Skylar! Adding an informative warning and manually setting the NaN values in both cases makes sense to me.

[lynna-deng]

The pull request requirements look sensible to me -- thank you for creating the template, Skylar! Noted also that tests relying on errors are not good practice.

[iupfal]

The PR requirements look good, thanks for adding these!

I tested on a few different python versions. The package doesn't work for newer python versions so maybe we can add this to the pyproject.toml (python = ">=3.9,<3.12").

Summary of testing:
3.13 can't install
3.12 can't install
3.11 installs; passes tests
3.10 installs, passes tests
3.9 installs; passes tests

[skygering]

I think in hindsight, I am going to move fixing the warnings to another PR, to be done at another time. It seems like their are complicating factors to fixing the trapz warning (i.e. depending on a library that Jamie wrote), and I would rather get the PR checklist in ASAP than fix the warnings at least for now.

However, I will add in the python version limiting.

[skygering]

Additionally, I got it to run on Python 3.12 and 3.13, so I think any of those changes will also be made in a separate PR if we determine they're needed. This will just be the PR checklist @kirbyh @iupfal @lynna-deng