[14188] | 1 | #region License Information
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| 2 | /* HeuristicLab
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| 3 | * Copyright (C) 2002-2018 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
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| 4 | *
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| 5 | * This file is part of HeuristicLab.
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| 6 | *
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| 7 | * HeuristicLab is free software: you can redistribute it and/or modify
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| 8 | * it under the terms of the GNU General Public License as published by
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| 9 | * the Free Software Foundation, either version 3 of the License, or
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| 10 | * (at your option) any later version.
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| 11 | *
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| 12 | * HeuristicLab is distributed in the hope that it will be useful,
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| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 15 | * GNU General Public License for more details.
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| 16 | *
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| 17 | * You should have received a copy of the GNU General Public License
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| 18 | * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
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| 19 | */
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| 20 | #endregion
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| 21 |
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| 22 | using HeuristicLab.Common;
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| 23 | using HeuristicLab.Core;
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| 24 | using HeuristicLab.Data;
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| 25 | using HeuristicLab.Operators;
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| 26 | using HeuristicLab.Optimization.Operators;
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| 27 | using HeuristicLab.Parameters;
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| 28 | using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
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| 29 | using HeuristicLab.Selection;
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| 30 |
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| 31 | namespace HeuristicLab.Algorithms.EvolutionStrategy {
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| 32 | /// <summary>
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| 33 | /// An operator which represents the main loop of an evolution strategy (EvolutionStrategy).
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| 34 | /// </summary>
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| 35 | [Item("EvolutionStrategyMainLoop", "An operator which represents the main loop of an evolution strategy (EvolutionStrategy).")]
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| 36 | [StorableClass]
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| 37 | public sealed class EvolutionStrategyMainLoop : AlgorithmOperator {
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| 38 | #region Parameter properties
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| 39 | public ValueLookupParameter<IRandom> RandomParameter {
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| 40 | get { return (ValueLookupParameter<IRandom>)Parameters["Random"]; }
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| 41 | }
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| 42 | public ValueLookupParameter<BoolValue> MaximizationParameter {
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| 43 | get { return (ValueLookupParameter<BoolValue>)Parameters["Maximization"]; }
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| 44 | }
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| 45 | public ScopeTreeLookupParameter<DoubleValue> QualityParameter {
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| 46 | get { return (ScopeTreeLookupParameter<DoubleValue>)Parameters["Quality"]; }
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| 47 | }
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| 48 | public ValueLookupParameter<DoubleValue> BestKnownQualityParameter {
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| 49 | get { return (ValueLookupParameter<DoubleValue>)Parameters["BestKnownQuality"]; }
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| 50 | }
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| 51 | public ValueLookupParameter<IntValue> PopulationSizeParameter {
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| 52 | get { return (ValueLookupParameter<IntValue>)Parameters["PopulationSize"]; }
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| 53 | }
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| 54 | public ValueLookupParameter<IntValue> ParentsPerChildParameter {
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| 55 | get { return (ValueLookupParameter<IntValue>)Parameters["ParentsPerChild"]; }
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| 56 | }
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| 57 | public ValueLookupParameter<IntValue> ChildrenParameter {
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| 58 | get { return (ValueLookupParameter<IntValue>)Parameters["Children"]; }
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| 59 | }
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| 60 | public ValueLookupParameter<BoolValue> PlusSelectionParameter {
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| 61 | get { return (ValueLookupParameter<BoolValue>)Parameters["PlusSelection"]; }
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| 62 | }
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| 63 | public IValueLookupParameter<BoolValue> ReevaluateElitesParameter {
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| 64 | get { return (IValueLookupParameter<BoolValue>)Parameters["ReevaluateElites"]; }
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| 65 | }
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| 66 | public ValueLookupParameter<IntValue> MaximumGenerationsParameter {
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| 67 | get { return (ValueLookupParameter<IntValue>)Parameters["MaximumGenerations"]; }
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| 68 | }
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| 69 | public ValueLookupParameter<IOperator> MutatorParameter {
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| 70 | get { return (ValueLookupParameter<IOperator>)Parameters["Mutator"]; }
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| 71 | }
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| 72 | public ValueLookupParameter<IOperator> RecombinatorParameter {
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| 73 | get { return (ValueLookupParameter<IOperator>)Parameters["Recombinator"]; }
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| 74 | }
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| 75 | public ValueLookupParameter<IOperator> EvaluatorParameter {
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| 76 | get { return (ValueLookupParameter<IOperator>)Parameters["Evaluator"]; }
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| 77 | }
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| 78 | public ValueLookupParameter<VariableCollection> ResultsParameter {
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| 79 | get { return (ValueLookupParameter<VariableCollection>)Parameters["Results"]; }
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| 80 | }
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| 81 | public ValueLookupParameter<IOperator> AnalyzerParameter {
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| 82 | get { return (ValueLookupParameter<IOperator>)Parameters["Analyzer"]; }
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| 83 | }
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| 84 | public LookupParameter<IntValue> EvaluatedSolutionsParameter {
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| 85 | get { return (LookupParameter<IntValue>)Parameters["EvaluatedSolutions"]; }
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| 86 | }
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| 87 | private ScopeParameter CurrentScopeParameter {
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| 88 | get { return (ScopeParameter)Parameters["CurrentScope"]; }
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| 89 | }
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| 90 | private ValueLookupParameter<IOperator> StrategyParameterManipulatorParameter {
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| 91 | get { return (ValueLookupParameter<IOperator>)Parameters["StrategyParameterManipulator"]; }
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| 92 | }
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| 93 | private ValueLookupParameter<IOperator> StrategyParameterCrossoverParameter {
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| 94 | get { return (ValueLookupParameter<IOperator>)Parameters["StrategyParameterCrossover"]; }
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| 95 | }
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| 96 |
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| 97 | public IScope CurrentScope {
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| 98 | get { return CurrentScopeParameter.ActualValue; }
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| 99 | }
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| 100 | #endregion
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| 101 |
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| 102 | [StorableConstructor]
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| 103 | private EvolutionStrategyMainLoop(bool deserializing) : base(deserializing) { }
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| 104 | private EvolutionStrategyMainLoop(EvolutionStrategyMainLoop original, Cloner cloner)
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| 105 | : base(original, cloner) {
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| 106 | }
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| 107 | public override IDeepCloneable Clone(Cloner cloner) {
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| 108 | return new EvolutionStrategyMainLoop(this, cloner);
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| 109 | }
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| 110 | public EvolutionStrategyMainLoop()
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| 111 | : base() {
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| 112 | Initialize();
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| 113 | }
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| 114 |
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| 115 | [StorableHook(HookType.AfterDeserialization)]
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| 116 | private void AfterDeserialization() {
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| 117 | // BackwardsCompatibility3.3
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| 118 | #region Backwards compatible code, remove with 3.4
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| 119 | if (!Parameters.ContainsKey("ReevaluateElites")) {
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| 120 | Parameters.Add(new ValueLookupParameter<BoolValue>("ReevaluateElites", "Flag to determine if elite individuals should be reevaluated (i.e., if stochastic fitness functions are used.)"));
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| 121 | }
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| 122 | #endregion
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| 123 | }
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| 124 |
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| 125 | private void Initialize() {
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| 126 | #region Create parameters
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| 127 | Parameters.Add(new ValueLookupParameter<IRandom>("Random", "A pseudo random number generator."));
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| 128 | Parameters.Add(new ValueLookupParameter<BoolValue>("Maximization", "True if the problem is a maximization problem, otherwise false."));
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| 129 | Parameters.Add(new ScopeTreeLookupParameter<DoubleValue>("Quality", "The value which represents the quality of a solution."));
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| 130 | Parameters.Add(new ValueLookupParameter<DoubleValue>("BestKnownQuality", "The best known quality value found so far."));
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| 131 | Parameters.Add(new ValueLookupParameter<IntValue>("PopulationSize", "µ (mu) - the size of the population."));
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| 132 | Parameters.Add(new ValueLookupParameter<IntValue>("ParentsPerChild", "ρ (rho) - how many parents should be recombined."));
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| 133 | Parameters.Add(new ValueLookupParameter<IntValue>("Children", "λ (lambda) - the size of the offspring population."));
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| 134 | Parameters.Add(new ValueLookupParameter<IntValue>("MaximumGenerations", "The maximum number of generations which should be processed."));
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| 135 | Parameters.Add(new ValueLookupParameter<BoolValue>("PlusSelection", "True for plus selection (elitist population), false for comma selection (non-elitist population)."));
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| 136 | Parameters.Add(new ValueLookupParameter<BoolValue>("ReevaluateElites", "Flag to determine if elite individuals should be reevaluated (i.e., if stochastic fitness functions are used.)"));
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| 137 | Parameters.Add(new ValueLookupParameter<IOperator>("Mutator", "The operator used to mutate solutions."));
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| 138 | Parameters.Add(new ValueLookupParameter<IOperator>("Recombinator", "The operator used to cross solutions."));
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| 139 | 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."));
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| 140 | Parameters.Add(new ValueLookupParameter<VariableCollection>("Results", "The variable collection where results should be stored."));
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| 141 | Parameters.Add(new ValueLookupParameter<IOperator>("Analyzer", "The operator used to analyze each generation."));
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| 142 | Parameters.Add(new LookupParameter<IntValue>("EvaluatedSolutions", "The number of times solutions have been evaluated."));
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| 143 | Parameters.Add(new ScopeParameter("CurrentScope", "The current scope which represents a population of solutions on which the EvolutionStrategy should be applied."));
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| 144 | Parameters.Add(new ValueLookupParameter<IOperator>("StrategyParameterManipulator", "The operator to mutate the endogeneous strategy parameters."));
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| 145 | Parameters.Add(new ValueLookupParameter<IOperator>("StrategyParameterCrossover", "The operator to cross the endogeneous strategy parameters."));
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| 146 | #endregion
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| 147 |
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| 148 | #region Create operators
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| 149 | VariableCreator variableCreator = new VariableCreator();
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| 150 | ResultsCollector resultsCollector1 = new ResultsCollector();
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| 151 | Placeholder analyzer1 = new Placeholder();
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| 152 | WithoutRepeatingBatchedRandomSelector selector = new WithoutRepeatingBatchedRandomSelector();
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| 153 | SubScopesProcessor subScopesProcessor1 = new SubScopesProcessor();
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| 154 | Comparator useRecombinationComparator = new Comparator();
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| 155 | ConditionalBranch useRecombinationBranch = new ConditionalBranch();
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| 156 | ChildrenCreator childrenCreator = new ChildrenCreator();
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| 157 | UniformSubScopesProcessor uniformSubScopesProcessor1 = new UniformSubScopesProcessor();
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| 158 | Placeholder recombinator = new Placeholder();
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| 159 | Placeholder strategyRecombinator = new Placeholder();
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| 160 | Placeholder strategyMutator1 = new Placeholder();
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| 161 | Placeholder mutator1 = new Placeholder();
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| 162 | SubScopesRemover subScopesRemover = new SubScopesRemover();
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| 163 | UniformSubScopesProcessor uniformSubScopesProcessor2 = new UniformSubScopesProcessor();
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| 164 | Placeholder strategyMutator2 = new Placeholder();
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| 165 | Placeholder mutator2 = new Placeholder();
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| 166 | UniformSubScopesProcessor uniformSubScopesProcessor3 = new UniformSubScopesProcessor();
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| 167 | Placeholder evaluator = new Placeholder();
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| 168 | SubScopesCounter subScopesCounter = new SubScopesCounter();
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| 169 | ConditionalBranch plusOrCommaReplacementBranch = new ConditionalBranch();
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| 170 | MergingReducer plusReplacement = new MergingReducer();
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| 171 | RightReducer commaReplacement = new RightReducer();
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| 172 | BestSelector bestSelector = new BestSelector();
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| 173 | RightReducer rightReducer = new RightReducer();
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| 174 | IntCounter intCounter = new IntCounter();
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| 175 | Comparator comparator = new Comparator();
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| 176 | Placeholder analyzer2 = new Placeholder();
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| 177 | ConditionalBranch conditionalBranch = new ConditionalBranch();
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| 178 | ConditionalBranch reevaluateElitesBranch = new ConditionalBranch();
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| 179 | SubScopesProcessor subScopesProcessor2 = new SubScopesProcessor();
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| 180 | UniformSubScopesProcessor uniformSubScopesProcessor4 = new UniformSubScopesProcessor();
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| 181 | Placeholder evaluator2 = new Placeholder();
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| 182 | SubScopesCounter subScopesCounter2 = new SubScopesCounter();
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| 183 |
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| 184 |
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| 185 | variableCreator.CollectedValues.Add(new ValueParameter<IntValue>("Generations", new IntValue(0))); // Class EvolutionStrategy expects this to be called Generations
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| 186 |
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| 187 | resultsCollector1.CollectedValues.Add(new LookupParameter<IntValue>("Generations"));
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| 188 | resultsCollector1.ResultsParameter.ActualName = "Results";
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| 189 |
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| 190 | analyzer1.Name = "Analyzer (placeholder)";
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| 191 | analyzer1.OperatorParameter.ActualName = AnalyzerParameter.Name;
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| 192 |
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| 193 | selector.Name = "ES Random Selector";
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| 194 | selector.RandomParameter.ActualName = RandomParameter.Name;
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| 195 | selector.ParentsPerChildParameter.ActualName = ParentsPerChildParameter.Name;
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| 196 | selector.ChildrenParameter.ActualName = ChildrenParameter.Name;
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| 197 |
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| 198 | useRecombinationComparator.Name = "ParentsPerChild > 1";
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| 199 | useRecombinationComparator.LeftSideParameter.ActualName = ParentsPerChildParameter.Name;
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| 200 | useRecombinationComparator.RightSideParameter.Value = new IntValue(1);
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| 201 | useRecombinationComparator.Comparison = new Comparison(ComparisonType.Greater);
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| 202 | useRecombinationComparator.ResultParameter.ActualName = "UseRecombination";
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| 203 |
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| 204 | useRecombinationBranch.Name = "Use Recombination?";
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| 205 | useRecombinationBranch.ConditionParameter.ActualName = "UseRecombination";
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| 206 |
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| 207 | childrenCreator.ParentsPerChild = null;
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| 208 | childrenCreator.ParentsPerChildParameter.ActualName = ParentsPerChildParameter.Name;
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| 209 |
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| 210 | recombinator.Name = "Recombinator (placeholder)";
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| 211 | recombinator.OperatorParameter.ActualName = RecombinatorParameter.Name;
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| 212 |
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| 213 | strategyRecombinator.Name = "Strategy Parameter Recombinator (placeholder)";
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| 214 | strategyRecombinator.OperatorParameter.ActualName = StrategyParameterCrossoverParameter.Name;
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| 215 |
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| 216 | strategyMutator1.Name = "Strategy Parameter Manipulator (placeholder)";
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| 217 | strategyMutator1.OperatorParameter.ActualName = StrategyParameterManipulatorParameter.Name;
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| 218 |
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| 219 | mutator1.Name = "Mutator (placeholder)";
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| 220 | mutator1.OperatorParameter.ActualName = MutatorParameter.Name;
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| 221 |
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| 222 | subScopesRemover.RemoveAllSubScopes = true;
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| 223 |
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| 224 | strategyMutator2.Name = "Strategy Parameter Manipulator (placeholder)";
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| 225 | strategyMutator2.OperatorParameter.ActualName = StrategyParameterManipulatorParameter.Name;
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| 226 |
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| 227 | mutator2.Name = "Mutator (placeholder)";
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| 228 | mutator2.OperatorParameter.ActualName = MutatorParameter.Name;
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| 229 |
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| 230 | uniformSubScopesProcessor3.Parallel.Value = true;
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| 231 |
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| 232 | evaluator.Name = "Evaluator (placeholder)";
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| 233 | evaluator.OperatorParameter.ActualName = EvaluatorParameter.Name;
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| 234 |
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| 235 | subScopesCounter.Name = "Increment EvaluatedSolutions";
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| 236 | subScopesCounter.ValueParameter.ActualName = EvaluatedSolutionsParameter.Name;
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| 237 |
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| 238 | plusOrCommaReplacementBranch.ConditionParameter.ActualName = PlusSelectionParameter.Name;
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| 239 |
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| 240 | bestSelector.CopySelected = new BoolValue(false);
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| 241 | bestSelector.MaximizationParameter.ActualName = MaximizationParameter.Name;
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| 242 | bestSelector.NumberOfSelectedSubScopesParameter.ActualName = PopulationSizeParameter.Name;
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| 243 | bestSelector.QualityParameter.ActualName = QualityParameter.Name;
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| 244 |
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| 245 | intCounter.Increment = new IntValue(1);
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| 246 | intCounter.ValueParameter.ActualName = "Generations";
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| 247 |
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| 248 | comparator.Comparison = new Comparison(ComparisonType.GreaterOrEqual);
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| 249 | comparator.LeftSideParameter.ActualName = "Generations";
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| 250 | comparator.ResultParameter.ActualName = "Terminate";
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| 251 | comparator.RightSideParameter.ActualName = MaximumGenerationsParameter.Name;
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| 252 |
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| 253 | analyzer2.Name = "Analyzer (placeholder)";
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| 254 | analyzer2.OperatorParameter.ActualName = AnalyzerParameter.Name;
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| 255 |
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| 256 | conditionalBranch.ConditionParameter.ActualName = "Terminate";
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| 257 |
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| 258 | reevaluateElitesBranch.ConditionParameter.ActualName = "ReevaluateElites";
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| 259 | reevaluateElitesBranch.Name = "Reevaluate elites ?";
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| 260 |
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| 261 | uniformSubScopesProcessor4.Parallel.Value = true;
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| 262 |
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| 263 | evaluator2.Name = "Evaluator (placeholder)";
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| 264 | evaluator2.OperatorParameter.ActualName = EvaluatorParameter.Name;
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| 265 |
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| 266 | subScopesCounter2.Name = "Increment EvaluatedSolutions";
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| 267 | subScopesCounter2.ValueParameter.ActualName = EvaluatedSolutionsParameter.Name;
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| 268 | #endregion
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| 269 |
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| 270 | #region Create operator graph
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| 271 | OperatorGraph.InitialOperator = variableCreator;
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| 272 | variableCreator.Successor = resultsCollector1;
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| 273 | resultsCollector1.Successor = analyzer1;
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| 274 | analyzer1.Successor = selector;
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| 275 | selector.Successor = subScopesProcessor1;
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| 276 | subScopesProcessor1.Operators.Add(new EmptyOperator());
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| 277 | subScopesProcessor1.Operators.Add(useRecombinationComparator);
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| 278 | subScopesProcessor1.Successor = plusOrCommaReplacementBranch;
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| 279 | useRecombinationComparator.Successor = useRecombinationBranch;
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| 280 | useRecombinationBranch.TrueBranch = childrenCreator;
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| 281 | useRecombinationBranch.FalseBranch = uniformSubScopesProcessor2;
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| 282 | useRecombinationBranch.Successor = uniformSubScopesProcessor3;
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| 283 | childrenCreator.Successor = uniformSubScopesProcessor1;
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| 284 | uniformSubScopesProcessor1.Operator = recombinator;
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| 285 | uniformSubScopesProcessor1.Successor = null;
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| 286 | recombinator.Successor = strategyRecombinator;
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| 287 | strategyRecombinator.Successor = strategyMutator1;
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| 288 | strategyMutator1.Successor = mutator1;
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| 289 | mutator1.Successor = subScopesRemover;
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| 290 | subScopesRemover.Successor = null;
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| 291 | uniformSubScopesProcessor2.Operator = strategyMutator2;
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| 292 | uniformSubScopesProcessor2.Successor = null;
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| 293 | strategyMutator2.Successor = mutator2;
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| 294 | mutator2.Successor = null;
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| 295 | uniformSubScopesProcessor3.Operator = evaluator;
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| 296 | uniformSubScopesProcessor3.Successor = subScopesCounter;
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| 297 | evaluator.Successor = null;
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| 298 | subScopesCounter.Successor = null;
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| 299 |
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| 300 | plusOrCommaReplacementBranch.TrueBranch = reevaluateElitesBranch;
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| 301 | reevaluateElitesBranch.TrueBranch = subScopesProcessor2;
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| 302 | reevaluateElitesBranch.FalseBranch = null;
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| 303 | subScopesProcessor2.Operators.Add(uniformSubScopesProcessor4);
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| 304 | subScopesProcessor2.Operators.Add(new EmptyOperator());
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| 305 | uniformSubScopesProcessor4.Operator = evaluator2;
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| 306 | uniformSubScopesProcessor4.Successor = subScopesCounter2;
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| 307 | subScopesCounter2.Successor = null;
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| 308 | reevaluateElitesBranch.Successor = plusReplacement;
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| 309 |
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| 310 | plusOrCommaReplacementBranch.FalseBranch = commaReplacement;
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| 311 | plusOrCommaReplacementBranch.Successor = bestSelector;
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| 312 | bestSelector.Successor = rightReducer;
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| 313 | rightReducer.Successor = intCounter;
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| 314 | intCounter.Successor = comparator;
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| 315 | comparator.Successor = analyzer2;
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| 316 | analyzer2.Successor = conditionalBranch;
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| 317 | conditionalBranch.FalseBranch = selector;
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| 318 | conditionalBranch.TrueBranch = null;
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| 319 | conditionalBranch.Successor = null;
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| 320 | #endregion
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| 321 | }
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| 322 |
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| 323 | public override IOperation Apply() {
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| 324 | if (MutatorParameter.ActualValue == null)
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| 325 | return null;
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| 326 | return base.Apply();
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| 327 | }
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| 328 | }
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| 329 | }
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