org.moeaframework.problem
Class RotatedProblems

java.lang.Object
  org.moeaframework.core.spi.ProblemProvider
      org.moeaframework.problem.RotatedProblems

public class RotatedProblems
extends ProblemProvider

Problem provider for rotated problems. Supports any problem available through ProblemProvider#getProblem(String). See RotatedProblem for details on how rotation is supported. Rotated problems are instantiated by providing the problem name prefixed with one of the following prefix patterns.

Prefix Pattern	Result
UNROT_	Unrotated problem
ROT_	Fully rotated instance, with each plane rotated by 45°
ROT(ANGLE)_	Fully rotated instance, with each plane rotated by ANGLE degrees. Use RAND for randomized rotations
ROT(K,ANGLE)_	K random rotation planes, each rotated by ANGLE degrees. Use ALL to rotate all planes

As an example, rotated 2D DTLZ2 instances can be created with "UNROT_DTLZ2_2", "ROT_DTLZ2_2", "ROT(30)_DTLZ2_2" and "ROT(10,RAND)_DTLZ2_2". Note that multiple calls to getProblem(String) may return instances with different rotations.

When comparing rotated problems against their unrotated versions, it is important to use the UNROT_ prefix for the unrotated problem. The act of rotating a problem expands the decision variable ranges slightly (imagine a 1 x 1 square that is rotated 45 degrees; the bounding box of the rotated square is approximately 1.4 x 1.4). The UNROT_ prefix ensures the unrotated version uses the same expanded decision variable ranges as the rotated variant.

Constructor Summary

RotatedProblems()
Constructs a problem provider for rotated problems.

Method Summary

Problem	getProblem(String name) Returns the problem with the specified name, or null if this provider does not support the problem.
NondominatedPopulation	getReferenceSet(String name) Returns the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available.

Methods inherited from class java.lang.Object

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

Constructor Detail

RotatedProblems

public RotatedProblems()

Constructs a problem provider for rotated problems.

Method Detail

getProblem

public Problem getProblem(String name)

Description copied from class: ProblemProvider

Returns the problem with the specified name, or null if this provider does not support the problem.

Specified by:

getProblem in class ProblemProvider

Parameters:

name - the problem name

Returns:

the problem with the specified name, or null if this provider does not support the problem

getReferenceSet

public NondominatedPopulation getReferenceSet(String name)

Description copied from class: ProblemProvider

Returns the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available.

Specified by:

getReferenceSet in class ProblemProvider

Parameters:

name - the problem name

Returns:

the reference set for the specified problem, or null if this provider does not support the problem or no reference set is available