Package org.moeaframework.problem

Class ScaledProblem

java.lang.Object

org.moeaframework.problem.ProblemWrapper

org.moeaframework.problem.ScaledProblem

All Implemented Interfaces:

AutoCloseable, Problem

public class ScaledProblem
extends ProblemWrapper

Decorator to create scaled variants of problems. The i-th objective is scaled by a factor of base^i. This can be used to determine if an algorithm is able to handle objectives of varying magnitudes.

Use loadScaledReferenceSet(File) or createScaledReferenceSet(File, File) to convert the original Pareto front file into the scaled version.

Field Summary

Fields inherited from class org.moeaframework.problem.ProblemWrapper

problem

Constructor Summary

Constructors

Constructor	Description
ScaledProblem(Problem problem, double base)	Constructs a new scaled problem.

Method Summary

Modifier and Type	Method	Description
void	createScaledReferenceSet(File file, File scaledFile)	Converts a reference set into its scaled version.
void	evaluate(Solution solution)	Evaluates the solution, updating the solution's objectives in place.
String	getName()	Returns the user-friendly name for this problem.
NondominatedPopulation	loadScaledReferenceSet(File file)	Loads the reference set file and scales the solutions.

Methods inherited from class org.moeaframework.problem.ProblemWrapper

close, getNumberOfConstraints, getNumberOfObjectives, getNumberOfVariables, newSolution

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.moeaframework.core.Problem

isType

Constructor Details

ScaledProblem

public ScaledProblem(Problem problem,
 double base)

Constructs a new scaled problem.

Parameters:

problem - the original, unscaled problem

base - the base for scaling

Method Details

getName

public String getName()

Description copied from interface: Problem

Returns the user-friendly name for this problem.

Specified by:

getName in interface Problem

Overrides:

getName in class ProblemWrapper

Returns:

the user-friendly name for this problem

evaluate

public void evaluate(Solution solution)

Description copied from interface: Problem

Evaluates the solution, updating the solution's objectives in place. Algorithms must explicitly call this method when appropriate to evaluate new solutions or reevaluate modified solutions.

Specified by:

evaluate in interface Problem

Overrides:

evaluate in class ProblemWrapper

Parameters:

solution - the solution to be evaluated

loadScaledReferenceSet

public NondominatedPopulation loadScaledReferenceSet(File file)
                                              throws IOException

Loads the reference set file and scales the solutions.

Parameters:

file - the reference set file

Returns:

the scaled reference set

Throws:

IOException - if an I/O error occurred

createScaledReferenceSet

public void createScaledReferenceSet(File file,
 File scaledFile)
                              throws IOException

Converts a reference set into its scaled version.

Parameters:

file - the original, unscaled reference set file

scaledFile - the scaled reference set file

Throws:

IOException - if an I/O error occurred