# Arsenal Gear Code Architecture

## Top-Level Population Class

The main way that users should interact with the code in python scripts
is through the top level `StellarPopulation` class. It has member
classes for both single and binary stellar sub-populations:

    StellarPopulation 
    params
        samp_mode       (stochastic, integrative)
        mstar           (total stellar mass)
        metallicity     (stellar metallicity)
        fbin            (total binary fraction)
    member classes
        SingleStarPop
        BinaryPop
        StellarOutput
            Atmosphere
            MechanicalFeedback
            Yields
    methods
        __init__()
        output(times)
        wind_mass_loss(times)
        radiation(times, band_data)
        sn_rate(times)
        yields(times)
        save_outputs(times)

## Abstract Stellar Population Classes

These classes contain information on the initial population of single
stars and binaries as well as methods for evolving them, which are
stellar evolution instances:

    SingleStarPop
    params
        IMF               (kroupa, chabrier, etc.)
        Evolution         (MIST, PARSEC, etc.)

    BinaryPop
    params
        IMF               (IMF of the primary)
        Evolution         (BPASS...)
        fbin_dist         (binary fraction distribution)
        q_dist            (mass ratio distribution)
        P_dist            (period distribution)
        e_dist            (eccentricity distribution)

## Abstract Stellar Evolution Classes

These classes contain interfaces to stellar evolution codes:

    SingleStellarEvolution
    params
        SingleStarPop
    methods
        props(times)          (get stellar properties)

    BinaryStellarEvolution
    params
        BinaryPop
    methods
        props_i(times)
        e(times)              (eccentricity evolution)
        P(times)              (Period evolution)

The `props` methods will return `StellarProperties` structures which are
containers for all of the properies of a star that are important for its
radiation and feedback.

## Abstract Atmosphere Classes

This provides the radiative output of a star based on its properties
such as bolometric luminosity, mass, radius, effective temperature,
metallicity:

    Atmosphere
    params
        StellarProperties
    methods
        get_band(times, band_data)
        get_spec(times)

## Abstract Mechanical Feedback Classes

Classes related to the return of mass, energy, and elements to the ISM:

    MechanicalFeedback
    params
        inputs
    member classes
        Winds
        Supernovae
        Yields

    Winds
    params
        StellarProperties
    methods
        mdotw(times)        (wind mass loss rates)
        vwind(times)        (wind velocities)

    Supernovae
    params
        StellarEvolution    (not necessary depending on choices)
    methods
        get_mmax(times)     (get maximum mass still alive)

    Yields
    params
        wind_ops
        sn_ops
    methods
        yi_wind             (wind yields)
        yi_sn(m)            (supernova yields as a funciton of mass)