org.apache.commons.math3.optimization.univariate

Class UnivariateMultiStartOptimizer<FUNC extends UnivariateFunction>

java.lang.Object

org.apache.commons.math3.optimization.univariate.UnivariateMultiStartOptimizer<FUNC>

Type Parameters:

FUNC - Type of the objective function to be optimized.

All Implemented Interfaces:

BaseOptimizer<UnivariatePointValuePair>, BaseUnivariateOptimizer<FUNC>

Deprecated.

As of 3.1 (to be removed in 4.0).

@Deprecated
public class UnivariateMultiStartOptimizer<FUNC extends UnivariateFunction>
extends java.lang.Object
implements BaseUnivariateOptimizer<FUNC>

Special implementation of the UnivariateOptimizer interface adding multi-start features to an existing optimizer. This class wraps a classical optimizer to use it several times in turn with different starting points in order to avoid being trapped into a local extremum when looking for a global one.

Since:

3.0

Field Summary

Fields

Modifier and Type	Field and Description
private RandomGenerator	generator Deprecated. Random generator for multi-start.
private int	maxEvaluations Deprecated. Maximal number of evaluations allowed.
private UnivariatePointValuePair[]	optima Deprecated. Found optima.
private BaseUnivariateOptimizer<FUNC>	optimizer Deprecated. Underlying classical optimizer.
private int	starts Deprecated. Number of starts to go.
private int	totalEvaluations Deprecated. Number of evaluations already performed for all starts.

Constructor Summary

Constructors

Constructor and Description
UnivariateMultiStartOptimizer(BaseUnivariateOptimizer<FUNC> optimizer, int starts, RandomGenerator generator) Deprecated. Create a multi-start optimizer from a single-start optimizer.

Method Summary

Methods

Modifier and Type	Method and Description
ConvergenceChecker<UnivariatePointValuePair>	getConvergenceChecker() Deprecated. Get the convergence checker.
int	getEvaluations() Deprecated. Get the number of evaluations of the objective function.
int	getMaxEvaluations() Deprecated. Get the maximal number of function evaluations.
UnivariatePointValuePair[]	getOptima() Deprecated. Get all the optima found during the last call to optimize.
UnivariatePointValuePair	optimize(int maxEval, FUNC f, GoalType goal, double min, double max) Deprecated. Find an optimum in the given interval.
UnivariatePointValuePair	optimize(int maxEval, FUNC f, GoalType goal, double min, double max, double startValue) Deprecated. Find an optimum in the given interval, start at startValue.
private void	sortPairs(GoalType goal) Deprecated. Sort the optima from best to worst, followed by null elements.

Methods inherited from class java.lang.Object

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

Field Detail

optimizer

private final BaseUnivariateOptimizer<FUNC extends UnivariateFunction> optimizer

Deprecated.

Underlying classical optimizer.

maxEvaluations

private int maxEvaluations

Deprecated.

Maximal number of evaluations allowed.

totalEvaluations

private int totalEvaluations

Deprecated.

Number of evaluations already performed for all starts.

starts

private int starts

Deprecated.

Number of starts to go.

generator

private RandomGenerator generator

Deprecated.

Random generator for multi-start.

optima

private UnivariatePointValuePair[] optima

Deprecated.

Found optima.

Constructor Detail

UnivariateMultiStartOptimizer

public UnivariateMultiStartOptimizer(BaseUnivariateOptimizer<FUNC> optimizer,
                             int starts,
                             RandomGenerator generator)

Deprecated.

Create a multi-start optimizer from a single-start optimizer.

Parameters:

optimizer - Single-start optimizer to wrap.

starts - Number of starts to perform. If starts == 1, the optimize methods will return the same solution as optimizer would.

generator - Random generator to use for restarts.

Throws:

NullArgumentException - if optimizer or generator is null.

NotStrictlyPositiveException - if starts < 1.

Method Detail

getConvergenceChecker

public ConvergenceChecker<UnivariatePointValuePair> getConvergenceChecker()

Deprecated.

Get the convergence checker.

Specified by:

getConvergenceChecker in interface BaseOptimizer<UnivariatePointValuePair>

Returns:

the object used to check for convergence.

getMaxEvaluations

public int getMaxEvaluations()

Deprecated.

Get the maximal number of function evaluations.

Specified by:

getMaxEvaluations in interface BaseOptimizer<UnivariatePointValuePair>

Returns:

the maximal number of function evaluations.

getEvaluations

public int getEvaluations()

Deprecated.

Get the number of evaluations of the objective function. The number of evaluations corresponds to the last call to the optimize method. It is 0 if the method has not been called yet.

Specified by:

getEvaluations in interface BaseOptimizer<UnivariatePointValuePair>

Returns:

the number of evaluations of the objective function.

getOptima

public UnivariatePointValuePair[] getOptima()

Deprecated.

Get all the optima found during the last call to optimize. The optimizer stores all the optima found during a set of restarts. The optimize method returns the best point only. This method returns all the points found at the end of each starts, including the best one already returned by the optimize method.
The returned array as one element for each start as specified in the constructor. It is ordered with the results from the runs that did converge first, sorted from best to worst objective value (i.e in ascending order if minimizing and in descending order if maximizing), followed by null elements corresponding to the runs that did not converge. This means all elements will be null if the optimize method did throw an exception. This also means that if the first element is not null, it is the best point found across all starts.

Returns:

an array containing the optima.

Throws:

MathIllegalStateException - if optimize has not been called.

optimize

public UnivariatePointValuePair optimize(int maxEval,
                                FUNC f,
                                GoalType goal,
                                double min,
                                double max)

Deprecated.

Find an optimum in the given interval. An optimizer may require that the interval brackets a single optimum.

Specified by:

optimize in interface BaseUnivariateOptimizer<FUNC extends UnivariateFunction>

Parameters:

maxEval - Maximum number of function evaluations.

f - Function to optimize.

goal - Type of optimization goal: either GoalType.MAXIMIZE or GoalType.MINIMIZE.

min - Lower bound for the interval.

max - Upper bound for the interval.

Returns:

a (point, value) pair where the function is optimum.

optimize

public UnivariatePointValuePair optimize(int maxEval,
                                FUNC f,
                                GoalType goal,
                                double min,
                                double max,
                                double startValue)

Deprecated.

Find an optimum in the given interval, start at startValue. An optimizer may require that the interval brackets a single optimum.

Specified by:

optimize in interface BaseUnivariateOptimizer<FUNC extends UnivariateFunction>

Parameters:

maxEval - Maximum number of function evaluations.

f - Function to optimize.

goal - Type of optimization goal: either GoalType.MAXIMIZE or GoalType.MINIMIZE.

min - Lower bound for the interval.

max - Upper bound for the interval.

startValue - Start value to use.

Returns:

a (point, value) pair where the function is optimum.

sortPairs

private void sortPairs(GoalType goal)

Deprecated.

Sort the optima from best to worst, followed by null elements.

Parameters:

goal - Goal type.