Free cookie consent management tool by TermsFeed Policy Generator

source: stable/HeuristicLab.Algorithms.ALPS/3.3/AlpsGeneticAlgorithmMainOperator.cs @ 13843

Last change on this file since 13843 was 13206, checked in by pfleck, 9 years ago

#2269 Fixed typos and renamed some stuff suggested by ascheibe and adapted project for mono.

  • The initialization of layer 0 is done similar to other algorithms where general initialization is done in the algorithm itself and variables used and produced during the main-loop is initialized in the main-loop-operator.
  • The GeneralizedRankSelector is used as default selector because it generally works the best (rank compensates the large quality range of multiple layers and high selection pressure via pressure-parameter). Proportional selection performs very badly because the selection pressure is too low for ALPS.
  • Concerning ReduceToPopulationSize in the EldersEmigrator, the behavior it is not completely clear in the original paper. Reducing the population to the population size seems the more logical way, therefore it is default. An empty layer could happen in extremely rare situations, but it never happens to me so far.
  • Concerning opening a new layer, when taking a closer look at the ages, all individual tends to be as old as possible, in the standard version with AgeInheritance==1. That means they usually get too old in exactly after the generation the AgeLimits for the current last layer states. This way it is not necessary to check if any individual becomes too old for the current last layer. For AgeInheritance<1 it can happen that there would actually be no need to open a new layer; however, it will be opened anyway.
File size: 12.9 KB
Line 
1#region License Information
2/* HeuristicLab
3 * Copyright (C) 2002-2015 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
4 *
5 * This file is part of HeuristicLab.
6 *
7 * HeuristicLab is free software: you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation, either version 3 of the License, or
10 * (at your option) any later version.
11 *
12 * HeuristicLab is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
19 */
20#endregion
21
22using HeuristicLab.Common;
23using HeuristicLab.Core;
24using HeuristicLab.Data;
25using HeuristicLab.Operators;
26using HeuristicLab.Optimization.Operators;
27using HeuristicLab.Parameters;
28using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
29using HeuristicLab.Selection;
30
31namespace HeuristicLab.Algorithms.ALPS {
32  [Item("AlpsGeneticAlgorithmMainOperator", "An operator that represents the core of an ALPS genetic algorithm.")]
33  [StorableClass]
34  public sealed class AlpsGeneticAlgorithmMainOperator : AlgorithmOperator {
35    #region Parameter properties
36    public IValueLookupParameter<IRandom> RandomParameter {
37      get { return (IValueLookupParameter<IRandom>)Parameters["Random"]; }
38    }
39
40    public IValueLookupParameter<IOperator> EvaluatorParameter {
41      get { return (IValueLookupParameter<IOperator>)Parameters["Evaluator"]; }
42    }
43    public IValueLookupParameter<IntValue> EvaluatedSolutionsParameter {
44      get { return (IValueLookupParameter<IntValue>)Parameters["EvaluatedSolutions"]; }
45    }
46    public IScopeTreeLookupParameter<DoubleValue> QualityParameter {
47      get { return (IScopeTreeLookupParameter<DoubleValue>)Parameters["Quality"]; }
48    }
49    public IValueLookupParameter<BoolValue> MaximizationParameter {
50      get { return (IValueLookupParameter<BoolValue>)Parameters["Maximization"]; }
51    }
52
53    public IValueLookupParameter<IntValue> PopulationSizeParameter {
54      get { return (IValueLookupParameter<IntValue>)Parameters["PopulationSize"]; }
55    }
56    public IValueLookupParameter<IOperator> SelectorParameter {
57      get { return (IValueLookupParameter<IOperator>)Parameters["Selector"]; }
58    }
59    public IValueLookupParameter<IOperator> CrossoverParameter {
60      get { return (IValueLookupParameter<IOperator>)Parameters["Crossover"]; }
61    }
62    public IValueLookupParameter<IOperator> MutatorParameter {
63      get { return (IValueLookupParameter<IOperator>)Parameters["Mutator"]; }
64    }
65    public IValueLookupParameter<PercentValue> MutationProbabilityParameter {
66      get { return (IValueLookupParameter<PercentValue>)Parameters["MutationProbability"]; }
67    }
68    public IValueLookupParameter<IntValue> ElitesParameter {
69      get { return (IValueLookupParameter<IntValue>)Parameters["Elites"]; }
70    }
71    public IValueLookupParameter<BoolValue> ReevaluateElitesParameter {
72      get { return (IValueLookupParameter<BoolValue>)Parameters["ReevaluateElites"]; }
73    }
74    public IValueLookupParameter<BoolValue> PlusSelectionParameter {
75      get { return (IValueLookupParameter<BoolValue>)Parameters["PlusSelection"]; }
76    }
77
78    public IScopeTreeLookupParameter<DoubleValue> AgeParameter {
79      get { return (IScopeTreeLookupParameter<DoubleValue>)Parameters["Age"]; }
80    }
81    public IValueLookupParameter<DoubleValue> AgeInheritanceParameter {
82      get { return (IValueLookupParameter<DoubleValue>)Parameters["AgeInheritance"]; }
83    }
84    public IValueLookupParameter<DoubleValue> AgeIncrementParameter {
85      get { return (IValueLookupParameter<DoubleValue>)Parameters["AgeIncrement"]; }
86    }
87    #endregion
88
89    [StorableConstructor]
90    private AlpsGeneticAlgorithmMainOperator(bool deserializing) : base(deserializing) { }
91    private AlpsGeneticAlgorithmMainOperator(AlpsGeneticAlgorithmMainOperator original, Cloner cloner)
92      : base(original, cloner) {
93    }
94    public override IDeepCloneable Clone(Cloner cloner) {
95      return new AlpsGeneticAlgorithmMainOperator(this, cloner);
96    }
97    public AlpsGeneticAlgorithmMainOperator()
98      : base() {
99      Parameters.Add(new ValueLookupParameter<IRandom>("Random", "A pseudo random number generator."));
100
101      Parameters.Add(new ValueLookupParameter<IOperator>("Evaluator", "The operator used to evaluate solutions. This operator is executed in parallel, if an engine is used which supports parallelization."));
102      Parameters.Add(new ValueLookupParameter<IntValue>("EvaluatedSolutions", "The number of times solutions have been evaluated."));
103      Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("Quality", "The value which represents the quality of a solution."));
104      Parameters.Add(new ValueLookupParameter<BoolValue>("Maximization", "True if the problem is a maximization problem, otherwise false."));
105
106      Parameters.Add(new ValueLookupParameter<IntValue>("PopulationSize", "The size of the population of solutions in each layer."));
107      Parameters.Add(new ValueLookupParameter<IOperator>("Selector", "The operator used to select solutions for reproduction."));
108      Parameters.Add(new ValueLookupParameter<IOperator>("Crossover", "The operator used to cross solutions."));
109      Parameters.Add(new ValueLookupParameter<IOperator>("Mutator", "The operator used to mutate solutions."));
110      Parameters.Add(new ValueLookupParameter<PercentValue>("MutationProbability", "The probability that the mutation operator is applied on a solution."));
111      Parameters.Add(new ValueLookupParameter<IntValue>("Elites", "The numer of elite solutions which are kept in each generation."));
112      Parameters.Add(new ValueLookupParameter<BoolValue>("ReevaluateElites", "Flag to determine if elite individuals should be reevaluated (i.e., if stochastic fitness functions are used.)"));
113      Parameters.Add(new ValueLookupParameter<BoolValue>("PlusSelection", "Include the parents in the selection of the invividuals for the next generation."));
114
115      Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("Age", "The age of individuals."));
116      Parameters.Add(new ValueLookupParameter<DoubleValue>("AgeInheritance", "A weight that determines the age of a child after crossover based on the older (1.0) and younger (0.0) parent."));
117      Parameters.Add(new ValueLookupParameter<DoubleValue>("AgeIncrement", "The value the age the individuals is incremented if they survives a generation."));
118
119
120      var numberOfSelectedParentsCalculator = new ExpressionCalculator() { Name = "NumberOfSelectedParents = 2 * (PopulationSize - (PlusSelection ? 0 : Elites))" };
121      var selector = new Placeholder() { Name = "Selector (Placeholder)" };
122      var subScopesProcessor1 = new SubScopesProcessor();
123      var childrenCreator = new ChildrenCreator();
124      var uniformSubScopesProcessor1 = new UniformSubScopesProcessor();
125      var crossover = new Placeholder() { Name = "Crossover (Placeholder)" };
126      var stochasticBranch = new StochasticBranch() { Name = "MutationProbability" };
127      var mutator = new Placeholder() { Name = "Mutator (Placeholder)" };
128      var ageCalculator = new WeightingReducer() { Name = "Calculate Age" };
129      var subScopesRemover = new SubScopesRemover();
130      var uniformSubScopesProcessor2 = new UniformSubScopesProcessor();
131      var evaluator = new Placeholder() { Name = "Evaluator (Placeholder)" };
132      var subScopesCounter = new SubScopesCounter() { Name = "Increment EvaluatedSolutions" };
133      var replacementBranch = new ConditionalBranch() { Name = "PlusSelection?" };
134      var replacementMergingReducer = new MergingReducer();
135      var replacementBestSelector = new BestSelector();
136      var replacementRightReducer = new RightReducer();
137      var subScopesProcessor2 = new SubScopesProcessor();
138      var bestSelector = new BestSelector();
139      var rightReducer = new RightReducer();
140      var mergingReducer = new MergingReducer();
141      var reevaluateElitesBranch = new ConditionalBranch() { Name = "Reevaluate elites ?" };
142      var incrementAgeProcessor = new UniformSubScopesProcessor();
143      var ageIncrementor = new DoubleCounter() { Name = "Increment Age" };
144
145      OperatorGraph.InitialOperator = numberOfSelectedParentsCalculator;
146
147      numberOfSelectedParentsCalculator.CollectedValues.Add(new LookupParameter<IntValue>(PopulationSizeParameter.Name));
148      numberOfSelectedParentsCalculator.CollectedValues.Add(new LookupParameter<IntValue>(ElitesParameter.Name));
149      numberOfSelectedParentsCalculator.CollectedValues.Add(new LookupParameter<BoolValue>(PlusSelectionParameter.Name));
150      numberOfSelectedParentsCalculator.ExpressionResultParameter.ActualName = "NumberOfSelectedSubScopes";
151      numberOfSelectedParentsCalculator.ExpressionParameter.Value = new StringValue("PopulationSize 0 Elites PlusSelection if - 2 * toint");
152      numberOfSelectedParentsCalculator.Successor = selector;
153
154      selector.OperatorParameter.ActualName = SelectorParameter.Name;
155      selector.Successor = subScopesProcessor1;
156
157      subScopesProcessor1.Operators.Add(new EmptyOperator());
158      subScopesProcessor1.Operators.Add(childrenCreator);
159      subScopesProcessor1.Successor = replacementBranch;
160
161      childrenCreator.ParentsPerChild = new IntValue(2);
162      childrenCreator.Successor = uniformSubScopesProcessor1;
163
164      uniformSubScopesProcessor1.Operator = crossover;
165      uniformSubScopesProcessor1.Successor = uniformSubScopesProcessor2;
166
167      crossover.OperatorParameter.ActualName = CrossoverParameter.Name;
168      crossover.Successor = stochasticBranch;
169
170      stochasticBranch.ProbabilityParameter.ActualName = MutationProbabilityParameter.Name;
171      stochasticBranch.RandomParameter.ActualName = RandomParameter.Name;
172      stochasticBranch.FirstBranch = mutator;
173      stochasticBranch.SecondBranch = null;
174      stochasticBranch.Successor = ageCalculator;
175
176      mutator.OperatorParameter.ActualName = MutatorParameter.Name;
177      mutator.Successor = null;
178
179      ageCalculator.ParameterToReduce.ActualName = AgeParameter.Name;
180      ageCalculator.TargetParameter.ActualName = AgeParameter.Name;
181      ageCalculator.WeightParameter.ActualName = AgeInheritanceParameter.Name;
182      ageCalculator.Successor = subScopesRemover;
183
184      subScopesRemover.RemoveAllSubScopes = true;
185      subScopesRemover.Successor = null;
186
187      uniformSubScopesProcessor2.Parallel.Value = true;
188      uniformSubScopesProcessor2.Operator = evaluator;
189      uniformSubScopesProcessor2.Successor = subScopesCounter;
190
191      evaluator.OperatorParameter.ActualName = EvaluatorParameter.Name;
192      evaluator.Successor = null;
193
194      subScopesCounter.ValueParameter.ActualName = EvaluatedSolutionsParameter.Name;
195      subScopesCounter.AccumulateParameter.Value = new BoolValue(true);
196      subScopesCounter.Successor = null;
197
198      replacementBranch.ConditionParameter.ActualName = PlusSelectionParameter.Name;
199      replacementBranch.TrueBranch = replacementMergingReducer;
200      replacementBranch.FalseBranch = subScopesProcessor2;
201      replacementBranch.Successor = incrementAgeProcessor;
202
203      replacementMergingReducer.Successor = replacementBestSelector;
204
205      replacementBestSelector.NumberOfSelectedSubScopesParameter.ActualName = PopulationSizeParameter.Name;
206      replacementBestSelector.CopySelected = new BoolValue(false);
207      replacementBestSelector.Successor = replacementRightReducer;
208
209      replacementRightReducer.Successor = reevaluateElitesBranch;
210
211      subScopesProcessor2.Operators.Add(bestSelector);
212      subScopesProcessor2.Operators.Add(new EmptyOperator());
213      subScopesProcessor2.Successor = mergingReducer;
214
215      bestSelector.CopySelected = new BoolValue(false);
216      bestSelector.MaximizationParameter.ActualName = MaximizationParameter.Name;
217      bestSelector.NumberOfSelectedSubScopesParameter.ActualName = ElitesParameter.Name;
218      bestSelector.QualityParameter.ActualName = QualityParameter.Name;
219      bestSelector.Successor = rightReducer;
220
221      rightReducer.Successor = reevaluateElitesBranch;
222
223      mergingReducer.Successor = null;
224
225      reevaluateElitesBranch.ConditionParameter.ActualName = ReevaluateElitesParameter.Name;
226      reevaluateElitesBranch.TrueBranch = uniformSubScopesProcessor2;
227      reevaluateElitesBranch.FalseBranch = null;
228      reevaluateElitesBranch.Successor = null;
229
230
231      incrementAgeProcessor.Operator = ageIncrementor;
232      incrementAgeProcessor.Successor = null;
233
234      ageIncrementor.ValueParameter.ActualName = AgeParameter.Name;
235      ageIncrementor.IncrementParameter.Value = null;
236      ageIncrementor.IncrementParameter.ActualName = AgeIncrementParameter.Name;
237      ageIncrementor.Successor = null;
238    }
239  }
240}
Note: See TracBrowser for help on using the repository browser.