StateControl

Controls for functions related to state

GetIntitialState⭐

public override State GetInitialState()

Definition

Define the initial state.

Return

Type	Description	Default
State	The initial state.	Null

Example

public override State GetInitialState()
{
    CRPData data = DataManager.Instance.Data as CRPData;
    CRPState initState = new CRPState();

    initState.SetStateInfo(data.CRPFactory.Conveyors);

    return initState;
}

GetKey

public override string GetKey(State state)

Definition

Defines the key for the state.

Parameters

Type	Description
State	The state to define the key.

Return

Type	Description	Default
String	The key of the state.	Default Logic

Example (Default Logic)

public virtual string GetKey(State state)
{
    return state.Index.ToString();
}

GetFeasibleSolution

public override Solution GetFeasibleSolution(State state)

Definition

Define the logic to find a feasible solution based on a given State.

Parameters

Type	Description
State	The state to find a feasible solution.

Return

Type	Description	Default
Solution	The feasible solution.	Null

Example

public override Solution GetFeasibleSolution(State state)
{           
    CRPState crpState = state as CRPState;
    CRPState copiedState = crpState.Clone();
    copiedState.IsInitial = false;

    List<CRPState> states = new List<CRPState>();
    states.AddRange(copiedState.GetBestStatesBackward().Cast<CRPState>().ToList());

    while (copiedState.JobCount > 0)
    {
        Stage stage = new Stage(copiedState.Stage.Index + 1);
        copiedState.Stage = stage;

        CRPJob lastJob = copiedState.LastRetrievedJob;

        CRPConveyor sameColorConv = copiedState.GetSameColorConveyor(lastJob);

        CRPJob retrievedJob = null;
        if (sameColorConv != null)
        {
            retrievedJob = copiedState.RetrieveJob(sameColorConv.ConveyorNum);
        }
        else 
        {
            retrievedJob = copiedState.RetrieveJob();
        }

        double cost = 0;
        if (lastJob != null && lastJob.Color.ColorNumber != retrievedJob.Color.ColorNumber)
            cost = 1;

        copiedState.BestValue += cost;

        states.Add(copiedState);
        copiedState = copiedState.Clone();
    }

    Solution feasibleSol = new Solution(states);

    return feasibleSol;
}

CanPruneByOptimality

public override bool CanPruneByOptimality(State state, ObjectiveFunctionType objFuncType, double pruneTolerance)

Definition

Determines whether a given state can be pruned without loss of optimality. If the state satisfies the prune conditions, it is excluded.

Parameters

Type	Description
State	The state to be judged.
ObjectiveFunctionType	The type of objective function in the problem.
Double	The tolerance used for the comparison condition when determining the optimal condition.

Type	Description	Default
Boolean	True: Prunes the state. False: Do not prune the state.	Default Logic

Example (Default Logic)

public override bool CanPruneByOptimality(State state, ObjectiveFunctionType objFuncType, double pruneTolerance)
{
    BoundManager boundManager = BoundManager.Instance;

    double bestPrimalBound = boundManager.BestPrimalBound;
    double dualBound = state.DualBound;
    double bestValue = state.BestValue;

    double rootDualBound = boundManager.RootDualBound;

    if (objFuncType == ObjectiveFunctionType.Minimize)
    {
        if (dualBound < rootDualBound - bestValue)
            dualBound = rootDualBound - bestValue;

        if (bestPrimalBound + pruneTolerance <= bestValue + dualBound)
            return true;
        else
            return false;
    }
    else
    {
        if (dualBound > rootDualBound - bestValue)
            dualBound = rootDualBound - bestValue;

        if (bestPrimalBound >= bestValue + dualBound + pruneTolerance)
            return true;
        else
            return false;
    }
}