Adding vertical neutral-neutral friction

[robfleur]

Description

Addresses #80

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change that adds functionality)

How Has This Been Tested?

I added output (with verbose level 4) that prints each coefficient from the vector.

Test configuration

• Operating system: macOS Ventura 13.1
• Compiler, version number: gcc Apple clang version 14.0.0

Checklist:

• [N/A] Make sure you are merging into the develop (not master) branch
• [X ] My code follows the style guidelines of this project
• [X ] I have performed a self-review of my own code
• [X ] I have commented my code, particularly in hard-to-understand areas
• [N/A] I have made corresponding changes to the documentation
• [X] My changes generate no new warnings
• [X] I have added tests that prove my fix is effective or that my feature works
• [N/A] New and existing unit tests pass locally with my changes
• [N/A] Any dependent changes have been merged and published in downstream modules
• [N/A] Add a note to CHANGELOG.md, summarizing the changes

[aburrell]

@roober-t can you rename this pull request to reflect the changes instead of calling it "develop"? Perhaps something like "Adding vertical neutral-neutral friction"?

[robfleur]

Since the initial pull request, I have added a newline to the bottom of ion_neutral_collision_frequencies. I also got rid of all extraneous comments throughout the code, including a few print statements in read_collision_file.cpp.

[aaronjridley]

@aburrell - can you do a quick check of this? I have cleaned it all up, made a test, and verified that everything works (found a major bug in the vertical gradient for non-uniform grids!). This should work well with the vertical advection pull request that is pending.

[aaronjridley]

Fixed some of the formatting changes that were suggested, merged the changes with the develop branch (removed report and input from the function calls), and fixed some bugs.