Add a problem

To add a new problem to OptimalControlProblems, you need to follow these steps:

1. Create a new file in the ext/MetaData directory with the name of your problem and containing the needed information about the problem in a dictionary. For instance, if your problem is called new_problem, create a file named new_problem.jl. The dictionary should follow the template:

new_problem_meta = Dict(
    :name => "new_problem", # Name of the problem
    :nh => nothing,         # Number of discretization points
    :nvar => nothing,       # Number of variables
    :ncon => nothing,       # Number of constraints
    :minimize => true       # Whether the problem is a minimization problem
)

The use of nothing in the dictionary is allowed and is used to indicate that the information is not available yet. Once you have the information, you can update the dictionary with the correct values.

2. Define the OptimalControl model of the problem in another file in the ext/OptimalControlModels directory.

"""
    Description of the new problem
"""
function OptimalControlProblems.new_problem(::OptimalControlBackend; nh::Int=default_value)
    @def ocp begin
        # Define the problem here
        # ...
    end

    # Initial guess for the problem
    init = () 

    # Obtain the NLPModel + DOCP
    docp, nlp = direct_transcription(ocp; init=init, grid_size=nh)

    return docp, nlp
end

3. Define the JuMP model of the problem in a new file in the ext/JuMPModels directory.

"""
    Description of the new problem
"""
function OptimalControlProblems.new_problem(::JuMPBackend; nh::Int=default_value)
    model = JuMP.Model()

    # Define the problem here
    # ...

    return model
end