Package org.moeaframework.problem

Class RotatedProblem

java.lang.Object

org.moeaframework.problem.ProblemWrapper

org.moeaframework.problem.RotatedProblem

All Implemented Interfaces:

AutoCloseable, Problem

public class RotatedProblem
extends ProblemWrapper

Decorator to create rotated variants of test problems. The rotation is defined by a rotation matrix, which should be orthogonal and have a determinant of 1. See RotationMatrixBuilder for a utility to quickly construct rotation matrices.

Regardless of the rotation, all rotated instances use expanded lower and upper bounds for the decision variables. An additional constraint is added to account for solutions existing in this expanded region, which are not in the original unrotated problem. This expansion is consistent across all rotations, which ensures the volume of the constraint-violating expanded region is constant across all instances of a problem.

Field Summary

Fields inherited from class org.moeaframework.problem.ProblemWrapper

problem

Constructor Summary

Constructors

Constructor	Description
RotatedProblem(Problem problem, org.apache.commons.math3.linear.RealMatrix rotation)	Decorates the specified problem, creating a rotated instance using the specified rotation matrix.

Method Summary

Modifier and Type	Method	Description
void	evaluate(Solution solution)	Evaluates the solution, updating the solution's objectives in place.
String	getName()	Returns the user-friendly name for this problem.
int	getNumberOfConstraints()	Returns the number of constraints defined by this problem.
Solution	newSolution()	Returns a new solution for this problem.

Methods inherited from class org.moeaframework.problem.ProblemWrapper

close, getNumberOfObjectives, getNumberOfVariables

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

RotatedProblem

public RotatedProblem(Problem problem,
 org.apache.commons.math3.linear.RealMatrix rotation)

Decorates the specified problem, creating a rotated instance using the specified rotation matrix.

Parameters:

problem - the original unrotated problem

rotation - the rotation matrix

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

getNumberOfConstraints

public int getNumberOfConstraints()

Description copied from interface: Problem

Returns the number of constraints defined by this problem.

Specified by:

getNumberOfConstraints in interface Problem

Overrides:

getNumberOfConstraints in class ProblemWrapper

Returns:

the number of constraints defined by 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

newSolution

public Solution newSolution()

Description copied from interface: Problem

Returns a new solution for this problem. Implementations must initialize the variables so that the valid range of values is defined, but typically leave the actual value at a default or undefined state.

Specified by:

newSolution in interface Problem

Overrides:

newSolution in class ProblemWrapper

Returns:

a new solution for this problem