---
tags: dispersion, minutes
---

# PlasmaPy Dispersion Meeting | Thursday 2020 November 19 at 14:00 PT / 17:00 ET

[](https://hackmd.io/XDImSQ8iTsOxvtrGzHFexw)

### Video Conference Information
* Instant messaging: [Matrix](https://element.im/app/#/room/#plasmapy:openastronomy.org) and [Gitter](https://gitter.im/PlasmaPy/Lobby)
* [GitHub Minutes Repository](https://github.com/PlasmaPy/plasmapy-meeting-notes)
* [Dispersion Sub-directory](https://github.com/PlasmaPy/plasmapy-meeting-notes/tree/master/dispersion_2020-present)
* [PlasmaPy on GitHub](https://github.com/PlasmaPy/plasmapy) ([pull requests](https://github.com/PlasmaPy/plasmapy/pulls), [issues](https://github.com/PlasmaPy/plasmapy/issues))
* [PlasmaPy Enhancement Proposals on GitHub](https://github.com/PlasmaPy/PlasmaPy-PLEPs)
* [PlasmaPy Google Calendar](https://calendar.google.com/calendar?cid=bzVsb3ZkcW0zaWxsam00ZTlrMDd2cmw5bWdAZ3JvdXAuY2FsZW5kYXIuZ29vZ2xlLmNvbQ)
* GitHub Project: None at the moment

## Attendees

1. Erik
2. Ramiz
3. Ben

## Action Items

1. [Erik] do another review of PR 932
2. [Erik] update and push changes to notebook associated w/ PR 932
3. [Ramiz & Erik] will think new name for `two_fluid_dispersion_soluntion()` in PR 932 (possibly `two_fluid_bellan_solution()`).
4. [Ramiz] will create `plasmapy/dispersion/analytical/` in followup PR to PR 932
5. [Ramiz] will open an Issue outlining the two fluid analytical solutions he's woring on for PR 932 and the followup PRs

## Agenda (please feel free to edit or add items)

1. Introductions
2. GitHub Project: None at the moment
3. What's the decision on pkg structurn?
4. Cleaning up notebook
5. papers
* bellan2012 - DOI: [10.1029/2012JA017856](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2012JA017856)
* xie2014 - DOI: [10.1016/j.cpc.2013.10.012](https://doi.org/10.1016/j.cpc.2013.10.012)
7. Issues
1. ...
2. ...
8. Pull requests in progress
1. [PR #932](https://github.com/PlasmaPy/PlasmaPy/pull/932): 1st analytical solution

## Minutes

* sub-pkg structure

    plasmapy
    +-- dispersion
    |   +-- analytical/  # for solutions
    |   +-- numerical/  # for solvers
    |   +-- __init__.py
    |   +-- core.py

* possible solvers
* fluid solvers from xenon: https://github.com/liangwang0734/xenon/blob/master/fluid/fluid_dr.py
* could use these as a basis for our solver...would need to properly cite
* [Erik] will make changes to jupyter notebook and push it for PR #932
* Ramiz has currently identified 5 analystical expression (3 from bellan2012)
* Ramiz has several expessions being coded in other branch and awaiting PR 932 to be complete before opening separate PRs
* all expressions come from a two fluid solutions
* idea is for each branch to have their own functions and then have a factory function `two_fluid_solution()` that could call the requested branch
* possible model

        def two_fluid_solution(branch="ballan"):
            """This is a factory function."""
            _solns = {
                "bellan": two_fluid_bellan,
                "hasegawa": two_fluid_hasegawa,
            }
            _soln = _solns[banch]

            ...

        def two_fluid_bellan():
            ...

        def two_fluid_hasegawa():
            ...

* The current expression in PR 932 is named `two_fluid_dispersion_solution()` and should be given a more explicit name to distguish it from the other solutions...possibly `two_fluid_bellan_solution()` since bellan2012 is credited with the solution
* `two_fluid_hasegawa()` might not be given the *hasegawa* name since that author is not directly credited with the soln...instead have a name more repsentive of the branch or assumptions
* each analytical expression will have its own notebook
* WE SHOULD ADD EASTER EGGS