source: branches/2521_ProblemRefactoring/HeuristicLab.Problems.Instances.TSPLIB/3.3/TSPLIBTSPInstanceProvider.cs @ 17900

#region License Information
/* HeuristicLab
 * Copyright (C) Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.IO;
using System.Linq;

namespace HeuristicLab.Problems.Instances.TSPLIB {
  public class TSPLIBTSPInstanceProvider : TSPLIBInstanceProvider<TSPData> {

    public override string Name {
      get { return "TSPLIB (symmetric TSP)"; }
    }

    public override string Description {
      get { return "Traveling Salesman Problem Library"; }
    }

    protected override string FileExtension { get { return "tsp"; } }

    protected override TSPData LoadInstance(TSPLIBParser parser, IDataDescriptor descriptor = null) {
      parser.Parse();
      if (parser.FixedEdges != null) throw new InvalidDataException("TSP instance " + parser.Name + " contains fixed edges which are not supported by HeuristicLab.");
      var instance = new TSPData();
      instance.Dimension = parser.Dimension;
      instance.Coordinates = parser.Vertices != null ? parser.Vertices : parser.DisplayVertices;
      instance.Distances = parser.Distances;
      switch (parser.EdgeWeightType) {
        case TSPLIBEdgeWeightTypes.ATT:
          instance.DistanceMeasure = DistanceMeasure.Att; break;
        case TSPLIBEdgeWeightTypes.CEIL_2D:
          instance.DistanceMeasure = DistanceMeasure.UpperEuclidean; break;
        case TSPLIBEdgeWeightTypes.EUC_2D:
          instance.DistanceMeasure = DistanceMeasure.RoundedEuclidean; break;
        case TSPLIBEdgeWeightTypes.EUC_3D:
          throw new InvalidDataException("3D coordinates are not supported.");
        case TSPLIBEdgeWeightTypes.EXPLICIT:
          instance.DistanceMeasure = DistanceMeasure.Direct; break;
        case TSPLIBEdgeWeightTypes.GEO:
          instance.DistanceMeasure = DistanceMeasure.Geo; break;
        case TSPLIBEdgeWeightTypes.MAN_2D:
          instance.DistanceMeasure = DistanceMeasure.Manhattan; break;
        case TSPLIBEdgeWeightTypes.MAN_3D:
          throw new InvalidDataException("3D coordinates are not supported.");
        case TSPLIBEdgeWeightTypes.MAX_2D:
          instance.DistanceMeasure = DistanceMeasure.Maximum; break;
        case TSPLIBEdgeWeightTypes.MAX_3D:
          throw new InvalidDataException("3D coordinates are not supported.");
        default:
          throw new InvalidDataException("The given edge weight is not supported by HeuristicLab.");
      }

      instance.Name = parser.Name;
      instance.Description = parser.Comment
        + Environment.NewLine + Environment.NewLine
        + GetInstanceDescription();
      return instance;
    }

    protected override void LoadSolution(TSPLIBParser parser, TSPData instance) {
      parser.Parse();
      instance.BestKnownTour = parser.Tour.FirstOrDefault();
    }

    protected override void LoadQuality(double? bestQuality, TSPData instance) {
      instance.BestKnownQuality = bestQuality;
    }

    public TSPData LoadData(string tspFile, string tourFile, double? bestQuality) {
      var data = LoadInstance(new TSPLIBParser(tspFile));
      if (!String.IsNullOrEmpty(tourFile)) {
        var tourParser = new TSPLIBParser(tourFile);
        LoadSolution(tourParser, data);
      }
      if (bestQuality.HasValue)
        data.BestKnownQuality = bestQuality.Value;
      return data;
    }

    public override bool CanExportData => true;

    public override void ExportData(TSPData instance, string path) {
      using (var writer = new StreamWriter(File.OpenWrite(path))) {
        writer.WriteLine("NAME: " + instance.Name);
        writer.WriteLine("TYPE: TSP");
        writer.WriteLine("COMMENT: " + instance.Description.Replace(Environment.NewLine, " \\\\ " ));
        writer.WriteLine("DIMENSION: " + instance.Dimension);

        if (instance.DistanceMeasure == DistanceMeasure.Euclidean) {
          // TSPLIB only knows rounded euclidean distance
          instance.Distances = instance.GetDistanceMatrix();
          instance.DistanceMeasure = DistanceMeasure.Direct;
        }

        if (instance.DistanceMeasure == DistanceMeasure.Direct) {
          writer.WriteLine("EDGE_WEIGHT_TYPE: EXPLICIT");
          writer.WriteLine("EDGE_WEIGHT_FORMAT: UPPER_ROW");
          if (instance.Coordinates != null && instance.Coordinates.GetLength(1) == 2) {
            writer.WriteLine("DISPLAY_DATA_TYPE: TWOD_DISPLAY");
          }
        } else {
          writer.Write("EDGE_WEIGHT_TYPE: ");
          switch (instance.DistanceMeasure) {
            case DistanceMeasure.RoundedEuclidean:
              writer.WriteLine("EUC_2D");
              break;
            case DistanceMeasure.UpperEuclidean:
              writer.WriteLine("CEIL_2D");
              break;
            case DistanceMeasure.Att:
              writer.WriteLine("ATT");
              break;
            case DistanceMeasure.Geo:
              writer.WriteLine("GEO");
              break;
            case DistanceMeasure.Manhattan:
              writer.WriteLine("MAN_2D");
              break;
            case DistanceMeasure.Maximum:
              writer.WriteLine("MAX_2D");
              break;
            default: throw new InvalidOperationException("Unknown distance measure: " + instance.DistanceMeasure);
          }
          writer.WriteLine("DISPLAY_DATA_TYPE: COORD_DISPLAY");
        }

        if (instance.DistanceMeasure == DistanceMeasure.Direct) {
          writer.WriteLine("EDGE_WEIGHT_SECTION");
          for (var i = 0; i < instance.Distances.GetLength(0) - 1; i++) {
            for (var j = i + 1; j < instance.Distances.GetLength(1); j++) {
              writer.Write(instance.Distances[i, j] + " ");
            }
            writer.WriteLine();
          }
        }

        if (instance.Coordinates != null && instance.Coordinates.GetLength(1) == 2) {
          if (instance.DistanceMeasure == DistanceMeasure.Direct)
            writer.WriteLine("DISPLAY_DATA_SECTION");
          else writer.WriteLine("NODE_COORD_SECTION");
          for (var i = 1; i <= instance.Coordinates.GetLength(0); i++) {
            writer.WriteLine(i + " " + instance.Coordinates[i - 1, 0] + " " + instance.Coordinates[i - 1, 1]);
          }
        }
        writer.WriteLine("EOF");
        writer.Flush();
      }
    }
  }
}