Advanced Control

Manually running each step

If you need more control, you can create the energy problem first, then the optimization model inside it, and finally ask for it to be solved.

First create the DuckDB connection, populate the data, and create an empty EnergyProblem:

using DuckDB, TulipaIO, TulipaEnergyModel

cp(joinpath(pkgdir(TulipaEnergyModel), "test", "inputs", "Tiny"), "example-data") # Copy the path to the test folder
input_dir = "example-data"
connection = DBInterface.connect(DuckDB.DB)
read_csv_folder(connection, input_dir; schemas = TulipaEnergyModel.schema_per_table_name)
energy_problem = EnergyProblem(connection)

The energy problem does not have a model yet:

energy_problem.model === nothing

To create the internal model, call the function create_model!.

create_model!(energy_problem)
energy_problem.model

Now the internal model has been created and you can see the number of variables and constraints being used.

The model has not been solved yet, which can be verified through the solved flag inside the energy problem:

energy_problem.solved

Finally, you can solve the model:

solve_model!(energy_problem)

To compute the solution and save it in the DuckDB connection, you can use

save_solution!(energy_problem)

The solutions will be saved in the variable and constraints tables. To save the solution to CSV files, you can use export_solution_to_csv_files

mkdir("output_folder")
export_solution_to_csv_files("output_folder", energy_problem)

The objective value and the termination status are also included in the energy problem:

energy_problem.objective_value, energy_problem.termination_status

Manually creating all structures without EnergyProblem

The EnergyProblem structure holds various internal structures, including the JuMP model and the DuckDB connection. There is currently no reason to manually create and maintain these structures yourself, so we recommend that you use the previous sections instead.

To avoid having to update this documentation whenever we make changes to the internals of TulipaEnergyModel before the v1.0.0 release, we will keep this section empty until then.