plan first quacs implementation

[K20shores]

Now that chempas-a has some useable versions with musica and all of its components, it's time to start building quacs atop that.

Acceptance criteria

• A design for quacs is created
  • where it should live
  • some initial design ideas
  • a set of issues that detail an early version
• The design is model agnostic

Ideas

• There is a branch of MPAS that exposes data fields to python. We might be able to re-use some of that for chempas-a
    - Branch: https://github.com/islas/MPAS-Model/tree/python_io
    - Fortran wiring (mpas_atm_core.F): https://github.com/islas/MPAS-Model/blob/python_io/src/core_atmosphere/mpas_atm_core.F
    - Python demo (demo.py): https://github.com/islas/MPAS-Model/blob/python_io/src/pymodules/atmo/demo.py
    - The reusable pybind11 bridge library:
    - Repo: https://github.com/islas/pyio
    - Pointer→numpy wrapping (EmbeddedInterpreter.cpp): https://github.com/islas/pyio/blob/HEAD/src/pyio/EmbeddedInterpreter.cpp
    - Header (EmbeddedInterpreter.hpp): https://github.com/islas/pyio/blob/HEAD/src/pyio/EmbeddedInterpreter.hpp

[K20shores]

Related diagrams: