New components

When the extension to MIMOSA is significant, it is recommended to create a new component. This component will contain all the new variables, constraints, and parameters that are part of the module.

Create the new component

As an example, we will create a new component called "New component". To do this, create a new file in the mimosa/components folder called new_component.py:

MIMOSA file structure: create a new file

mimosa
│   abstract_model.py
│   mimosa.py
│
└─── components
    │   emissions.py
    │   mitigation.py
    │   new_component.py
    │   ...
│
└─── inputdata
    │   ...

A component always consists of a function get_constraints(m), in which all the new variables, parameters, and constraints are defined. The function needs to return a list of all the newly created constraints:

mimosa/components/new_component.py

from mimosa.common import (
    AbstractModel, Param, Var,
    GlobalConstraint, GlobalInitConstraint,
    RegionalConstraint, RegionalInitConstraint,
    quant
)

def get_constraints(m: AbstractModel):
    """
    Documentation of what the new component does
    """

    # New variables
    m.new_var = Var()

    # New parameters
    m.new_param = Param()

    # Create a list of all the new constraints
    constraints = [
        GlobalConstraint(...),
        ...
    ]

    # Return the list of constraints
    return constraints

Link the new component to the model

To link the new component to the model, import the new component in mimosa/abstract_model.py:

mimosa/abstract_model.py

from mimosa.components import new_component

def create_model():
    m = AbstractModel()

    # ... existing code ...

    ######################
    # Components
    ######################

    # Add the new component
    constraints.extend(new_component.get_constraints(m))

    # ... existing code ...

    return m