Package org.moeaframework.problem.single

Class Griewank

java.lang.Object

org.moeaframework.problem.AbstractProblem

org.moeaframework.problem.single.Griewank

All Implemented Interfaces:

AutoCloseable, Problem

public class Griewank
extends AbstractProblem

The single-objective Griewank problem with an optimum at x = (0, ..., 0) with f(x) = 0.

References:

1. Molga, M. and Smutnicki, C. Test Functions for Optimization Needs." (2005).

Field Summary

Fields inherited from class org.moeaframework.problem.AbstractProblem

numberOfConstraints, numberOfObjectives, numberOfVariables

Constructor Summary

Constructors

Constructor	Description
Griewank()	Constructs a new instance of the Griewank problem with two decision variables.
Griewank(int numberOfVariables)	Constructs a new instance of the Griewank problem.

Method Summary

Modifier and Type	Method	Description
void	evaluate(Solution solution)	Evaluates the solution, updating the solution's objectives in place.
NondominatedPopulation	getReferenceSet()	Returns the reference set, typically a single solution unless the problem has multiple local minima, for this single objective problem.
Solution	newSolution()	Returns a new solution for this problem.

Methods inherited from class org.moeaframework.problem.AbstractProblem

close, getName, getNumberOfConstraints, 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

Griewank

public Griewank()

Constructs a new instance of the Griewank problem with two decision variables.

Griewank

public Griewank(int numberOfVariables)

Constructs a new instance of the Griewank problem.

Parameters:

numberOfVariables - the number of decision variables

Method Details

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.

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.

Returns:

a new solution for this problem

getReferenceSet

public NondominatedPopulation getReferenceSet()

Returns the reference set, typically a single solution unless the problem has multiple local minima, for this single objective problem.

Returns:

the reference set