public override IOperation Apply() { IEnumerable <int> rows = GenerateRowsToEvaluate(); if (!rows.Any()) { return(base.Apply()); } var results = ResultCollection; // create empty parameter and result values if (ValidationBestSolutions == null) { ValidationBestSolutions = new ItemList <S>(); ValidationBestSolutionQualities = new ItemList <DoubleArray>(); results.Add(new Result(ValidationBestSolutionQualitiesParameter.Name, ValidationBestSolutionQualitiesParameter.Description, ValidationBestSolutionQualities)); results.Add(new Result(ValidationBestSolutionsParameter.Name, ValidationBestSolutionsParameter.Description, ValidationBestSolutions)); } //if the pareto front of best solutions shall be updated regardless of the quality, the list initialized empty to discard old solutions IList <double[]> trainingBestQualities; if (UpdateAlways.Value) { trainingBestQualities = new List <double[]>(); } else { trainingBestQualities = ValidationBestSolutionQualities.Select(x => x.ToArray()).ToList(); } #region find best trees IList <int> nonDominatedIndexes = new List <int>(); ISymbolicExpressionTree[] tree = SymbolicExpressionTree.ToArray(); bool[] maximization = Maximization.ToArray(); List <double[]> newNonDominatedQualities = new List <double[]>(); var evaluator = EvaluatorParameter.ActualValue; var problemData = ProblemDataParameter.ActualValue; IExecutionContext childContext = (IExecutionContext)ExecutionContext.CreateChildOperation(evaluator); var qualities = tree .Select(t => evaluator.Evaluate(childContext, t, problemData, rows)) .ToArray(); for (int i = 0; i < tree.Length; i++) { if (IsNonDominated(qualities[i], trainingBestQualities, maximization) && IsNonDominated(qualities[i], qualities, maximization)) { if (!newNonDominatedQualities.Contains(qualities[i], new DoubleArrayComparer())) { newNonDominatedQualities.Add(qualities[i]); nonDominatedIndexes.Add(i); } } } #endregion #region update Pareto-optimal solution archive if (nonDominatedIndexes.Count > 0) { ItemList <DoubleArray> nonDominatedQualities = new ItemList <DoubleArray>(); ItemList <S> nonDominatedSolutions = new ItemList <S>(); // add all new non-dominated solutions to the archive foreach (var index in nonDominatedIndexes) { S solution = CreateSolution(tree[index], qualities[index]); nonDominatedSolutions.Add(solution); nonDominatedQualities.Add(new DoubleArray(qualities[index])); } // add old non-dominated solutions only if they are not dominated by one of the new solutions for (int i = 0; i < trainingBestQualities.Count; i++) { if (IsNonDominated(trainingBestQualities[i], newNonDominatedQualities, maximization)) { if (!newNonDominatedQualities.Contains(trainingBestQualities[i], new DoubleArrayComparer())) { nonDominatedSolutions.Add(ValidationBestSolutions[i]); nonDominatedQualities.Add(ValidationBestSolutionQualities[i]); } } } results[ValidationBestSolutionsParameter.Name].Value = nonDominatedSolutions; results[ValidationBestSolutionQualitiesParameter.Name].Value = nonDominatedQualities; } #endregion return(base.Apply()); }
public override IOperation Apply() { var results = ResultCollection; // create empty parameter and result values if (TrainingBestSolutions == null) { TrainingBestSolutions = new ItemList <T>(); TrainingBestSolutionQualities = new ItemList <DoubleArray>(); results.Add(new Result(TrainingBestSolutionQualitiesParameter.Name, TrainingBestSolutionQualitiesParameter.Description, TrainingBestSolutionQualities)); results.Add(new Result(TrainingBestSolutionsParameter.Name, TrainingBestSolutionsParameter.Description, TrainingBestSolutions)); } if (!results.ContainsKey(TrainingBestSolutionParameterName)) { results.Add(new Result(TrainingBestSolutionParameterName, "", typeof(ISymbolicDataAnalysisSolution))); } //if the pareto front of best solutions shall be updated regardless of the quality, the list initialized empty to discard old solutions List <double[]> trainingBestQualities; if (UpdateAlways) { trainingBestQualities = new List <double[]>(); } else { trainingBestQualities = TrainingBestSolutionQualities.Select(x => x.ToArray()).ToList(); } ISymbolicExpressionTree[] trees = SymbolicExpressionTree.ToArray(); List <double[]> qualities = Qualities.Select(x => x.ToArray()).ToList(); bool[] maximization = Maximization.ToArray(); var nonDominatedIndividuals = new[] { new { Tree = default(ISymbolicExpressionTree), Qualities = default(double[]) } }.ToList(); nonDominatedIndividuals.Clear(); // build list of new non-dominated solutions for (int i = 0; i < trees.Length; i++) { if (IsNonDominated(qualities[i], nonDominatedIndividuals.Select(ind => ind.Qualities), maximization) && IsNonDominated(qualities[i], trainingBestQualities, maximization)) { for (int j = nonDominatedIndividuals.Count - 1; j >= 0; j--) { if (IsBetterOrEqual(qualities[i], nonDominatedIndividuals[j].Qualities, maximization)) { nonDominatedIndividuals.RemoveAt(j); } } nonDominatedIndividuals.Add(new { Tree = trees[i], Qualities = qualities[i] }); } } var nonDominatedSolutions = nonDominatedIndividuals.Select(x => new { Solution = CreateSolution(x.Tree, x.Qualities), Qualities = x.Qualities }).ToList(); nonDominatedSolutions.ForEach(s => s.Solution.Name = string.Join(",", s.Qualities.Select(q => q.ToString()))); #region update Pareto-optimal solution archive if (nonDominatedSolutions.Count > 0) { //add old non-dominated solutions only if they are not dominated by one of the new solutions for (int i = 0; i < trainingBestQualities.Count; i++) { if (IsNonDominated(trainingBestQualities[i], nonDominatedSolutions.Select(x => x.Qualities), maximization)) { nonDominatedSolutions.Add(new { Solution = TrainingBestSolutions[i], Qualities = TrainingBestSolutionQualities[i].ToArray() }); } } //assumes the the first objective is always the accuracy var sortedNonDominatedSolutions = maximization[0] ? nonDominatedSolutions.OrderByDescending(x => x.Qualities[0]) : nonDominatedSolutions.OrderBy(x => x.Qualities[0]); var trainingBestSolution = sortedNonDominatedSolutions.Select(s => s.Solution).First(); results[TrainingBestSolutionParameterName].Value = trainingBestSolution; TrainingBestSolutions = new ItemList <T>(sortedNonDominatedSolutions.Select(x => x.Solution)); results[TrainingBestSolutionsParameter.Name].Value = TrainingBestSolutions; TrainingBestSolutionQualities = new ItemList <DoubleArray>(sortedNonDominatedSolutions.Select(x => new DoubleArray(x.Qualities))); results[TrainingBestSolutionQualitiesParameter.Name].Value = TrainingBestSolutionQualities; } #endregion return(base.Apply()); }