using System; using System.Linq; using HeuristicLab.Analysis; using HeuristicLab.Data; using HeuristicLab.Encodings.PermutationEncoding; using HeuristicLab.Problems.Instances.QAPLIB; using HeuristicLab.Problems.QuadraticAssignment; using HeuristicLab.Random; public class GAQAPScript : HeuristicLab.Scripting.CSharpScriptBase { public override void Main() { DateTime start = DateTime.UtcNow; QuadraticAssignmentProblem qap; if (vars.Contains("qap")) qap = vars.qap; else { var provider = new DreznerQAPInstanceProvider(); var instance = provider.GetDataDescriptors().Single(x => x.Name == "dre56"); var data = provider.LoadData(instance); qap = new QuadraticAssignmentProblem(); qap.Load(data); vars.qap = qap; } const uint seed = 0; const int popSize = 100; const int generations = 1000; const double mutationRate = 0.05; var random = new MersenneTwister(seed); var population = new Permutation[popSize]; var qualities = new double[popSize]; var nextGen = new Permutation[popSize]; var nextQual = new double[popSize]; var qualityChart = new DataTable("Quality Chart"); var qualityRow = new DataRow("Best Quality"); qualityChart.Rows.Add(qualityRow); vars.qualityChart = qualityChart; for (int i = 0; i < popSize; i++) { population[i] = new Permutation(PermutationTypes.Absolute, qap.Weights.Rows, random); qualities[i] = QAPEvaluator.Apply(population[i], qap.Weights, qap.Distances); } var bestQuality = qualities.Min(); var bestQualityGeneration = 0; for (int g = 0; g < generations; g++) { var parents = population.SampleProportional(random, 2 * popSize, qualities, windowing: true, inverseProportional: true).ToArray(); for (int i = 0; i < popSize; i++) { nextGen[i] = PartiallyMatchedCrossover.Apply(random, parents[i * 2], parents[i * 2 + 1]); if (random.NextDouble() < mutationRate) Swap2Manipulator.Apply(random, nextGen[i]); nextQual[i] = QAPEvaluator.Apply(nextGen[i], qap.Weights, qap.Distances); if (nextQual[i] < bestQuality) { bestQuality = nextQual[i]; bestQualityGeneration = g; } } qualityRow.Values.Add(bestQuality); Array.Copy(nextGen, population, popSize); Array.Copy(nextQual, qualities, popSize); } vars.elapsed = new TimeSpanValue(DateTime.UtcNow - start); vars.bestQuality = bestQuality; vars.bestQualityFoundAt = bestQualityGeneration; } }