com.anylogic.engine.OptimizationCallback

public abstract class OptimizationCallback
extends Object

This class is designed for usage in optimizations performed within custom experiments, see ExperimentOptimization.createOptimization(Engine, OptimizationCallback).

Usage example (the code of custom experiment, requires import com.opttek.optquest.*;):

 try {
        // Create Engine, initialize random number generator:
        Engine engine = createEngine();
        // Set stop time:
        engine.setStopTime(1);
 
        // Create optimization variable
        final COptQuestContinuousVariable v = new COptQuestContinuousVariable();
        v.SetLowerBound(0.0);
        v.SetUpperBound(100.0);
 
        // Create objective
        final COptQuestObjective obj = new COptQuestUserControlledObjective();
        obj.SetMinimize();
 
        // Create optimization engine
        final COptQuestOptimization opt = ExperimentOptimization.createOptimization(engine, new OptimizationCallback() {
 
                                @Override
                                public void evaluate(COptQuestOptimization optimization,
                                                COptQuestSolution solution, Engine engine) {
                                        try {
                                                // Create new top-level agent:
                                                Main root = new Main(engine, null, null);
                                                // Setup parameters of top-level agent here
                                                root.param = solution.GetVariableValue(v);
                                                // Prepare Engine for simulation:
                                                engine.start(root);
                                                // Start simulation in fast mode:
                                                engine.runFast();
                                                // Process results of simulation here
                                                solution.SetObjectiveValue(obj, root.objective);
                                                // Destroy the model:
                                                engine.stop();
                                        } catch (COptQuestException e) {
                                                traceln(e.Description());
                                        }
                                }
 
                                // Trace each iteration (optional!)
                                @Override
                                public void monitorStatus(COptQuestOptimization optimization,
                                                COptQuestSolution solution, Engine engine) {
                                        try {
                                                traceln(String.format(
                                                                "  %3d : %6.2f : %8.2f  -- %8.2f",
                                                                solution.GetIteration(),
                                                                solution.GetVariableValue(v),
                                                                solution.GetObjectiveValue(),
                                                                optimization.GetBestSolution() != null ? optimization
                                                                                .GetBestSolution().GetObjectiveValue(
                                                                                                obj) : Double.NaN));
                                        } catch (COptQuestException e) {
                                                traceln(e.Description());
                                        }
                                }
 
                        });
 
        // Setup optimization engine
        opt.AddVariable(v);
        opt.AddObjective(obj);
        // Set the number of iterations to run
        opt.SetMaximumIterations(500);
 
  // Add suggested solution (initial solution)
        COptQuestSolution suggestedSolution = opt.CreateSolution();
        suggestedSolution.SetVariableValue(v, 50.0);
        opt.AddSuggestedSolution(suggestedSolution);
 
        // Perform optimization
        opt.Optimize();
 
        // Output results
        COptQuestSolution bestSolution = opt.GetBestSolution();
        traceln("Best objective: " + format(bestSolution.GetObjectiveValue(obj)));
        traceln("Best parameter: " + format(bestSolution.GetVariableValue(v)));
 } catch (COptQuestException e) {
        traceln(e.Description());
 }

Author:

AnyLogic North America, LLC https://anylogic.com

See Also:

ExperimentOptimization.createOptimization(Engine, OptimizationCallback)

Constructor Summary

Constructor	Description
`OptimizationCallback()`

Method Summary

Modifier and Type	Method	Description
`abstract void`	`evaluate(com.opttek.optquest.COptQuestOptimization optimization, com.opttek.optquest.COptQuestSolution solution, Engine engine)`	This callback should evaluate a solution. This method is called at each iteration/replication of optimization. Please call `COptQuestVariable#GetCurrentValue()` to obtain calculated values of optimization parameters and save objective value using `COptQuestOptimization#SetCurrentObjectiveValue(double)` The most common implementation of this method is a single simulation (using runFast()) of a newly created (each time) model agent
`void`	`monitorStatus(com.opttek.optquest.COptQuestOptimization optimization, com.opttek.optquest.COptQuestSolution solution, Engine engine)`	This method is called at the end of each iteration (after `evaluate(COptQuestOptimization, COptQuestSolution, Engine)`). When this method is called, the solution has been checked for feasibility.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

OptimizationCallback

public OptimizationCallback()

Method Details

evaluate

public abstract void evaluate(com.opttek.optquest.COptQuestOptimization optimization,
 com.opttek.optquest.COptQuestSolution solution,
 Engine engine)

This callback should evaluate a solution.
This method is called at each iteration/replication of optimization.
Please call COptQuestVariable#GetCurrentValue() to obtain calculated values of optimization parameters and save objective value using COptQuestOptimization#SetCurrentObjectiveValue(double)
The most common implementation of this method is a single simulation (using runFast()) of a newly created (each time) model agent

Parameters:: optimization - optimization engine instance; solution - solution being evaluated; engine - AnyLogic engine instance

monitorStatus

public void monitorStatus(com.opttek.optquest.COptQuestOptimization optimization,
 com.opttek.optquest.COptQuestSolution solution,
 Engine engine)

This method is called at the end of each iteration (after evaluate(COptQuestOptimization, COptQuestSolution, Engine)).
When this method is called, the solution has been checked for feasibility.

Parameters:: optimization - optimization engine instance; solution - the solution; engine - AnyLogic engine instance

Class OptimizationCallback