Model Approach in SINDBAD

This documentation explains how to work with model approaches in SINDBAD. For a comprehensive understanding of SINDBAD's modeling framework, see the SINDBAD concept documentation.

INFO

When working with SINDBAD, it is highly recommended to utilize the built-in function generateSindbadApproach to create your model and approach files. This function automates the process of setting up the necessary structs and functions of the model, ensuring that your model adheres to the established conventions for code structure, performance tips, modularity, and documentation.

Check the documentation of the function for further details as:

using Sindbad
?generateSindbadApproach

Viewing Model Approaches

To view available model approaches and their implementations:

using Sindbad: showMethodsOf
showMethodsOf(LandEcosystem)

This will display all available model approaches that are subtypes of LandEcosystem.

Model Approach Structure

A model approach in SINDBAD typically follows this structure:

# Define the model type
abstract type newModel <: LandEcosystem end

@bounds @describe @units @timescale @with_kw struct newModel_v1{T1,T2} <: newModel
    param1::T1 = 1.0 | (2.0, 5.0) | "description 1" | "units 1" | ""
    param2::T2 = 0.0 | (1.0, 2.0) | "description 2" | "units 2" | ""
end

# Define the purpose
purpose(::Type{newModel}) = "Description of what this model does"

For more details about the modeling conventions and required methods, see the modeling conventions documentation.

Required Methods

1. define

function define(params::newModel_v1, forcing, land, helpers)
    ## unpack parameters, forcing and variables store in land
    @unpack_newModel_v1 params
    @unpack_nt (f1, f2) ⇐ forcing
    @unpack_nt var1 ⇐ land.diagnostics

    ## calculate variables
    new_var_1 = f1*param1 + param2 + var1*f2

    ## pack land variables
    @pack_nt begin
        new_var_1 ⇒ land.diagnostics
    end
    return land
end

• Initializes model-specific variables

• Sets up model parameters

• Returns modified land structure

For more information about variable initialization, see the land concept documentation.

2. compute

function compute(params::newModel_v1, forcing, land, helpers)
    ## unpack parameters, forcing and variables store in land
    @unpack_newModel_v1 params
    @unpack_nt (f1, f2) ⇐ forcing
    @unpack_nt var1 ⇐ land.diagnostics

    ## calculate variables
    var_1 = f1*param1 + param2 + f2

    ## pack land variables
    @pack_nt begin
        var_1 ⇒ land.diagnostics
    end
    return land
end

• Implements core model calculations

• Updates model state

• Returns modified land structure

Input Arguments

All models are defined as follows:

abstract type newModel <: LandEcosystem end

@bounds @describe @units @timescale @with_kw struct newModel_v1{T1,T2} <: newModel
    param1::T1 = 1.0 | (2.0, 5.0) | "description 1" | "units 1" | ""
    param2::T2 = 0.0 | (1.0, 2.0) | "description 2" | "units 2" | ""
end