#region License Information
/* HeuristicLab
* Copyright (C) 2002-2012 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 .
*/
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Optimization.Operators;
using HeuristicLab.Problems.VehicleRouting.Encodings;
using HeuristicLab.Problems.VehicleRouting.Encodings.Potvin;
namespace HeuristicLab.Problems.VehicleRouting {
///
/// An operator that performs similarity calculation between two vehicle routing solutions.
///
[Item("VRPSimilarityCalculator", "An operator that performs similarity calculation between two vehicle routing solutions.")]
public sealed class VRPSimilarityCalculator : SimilarityCalculator {
private VRPSimilarityCalculator(bool deserializing) : base(deserializing) { }
private VRPSimilarityCalculator(VRPSimilarityCalculator original, Cloner cloner) : base(original, cloner) { }
public VRPSimilarityCalculator() : base() { }
public override IDeepCloneable Clone(Cloner cloner) {
return new VRPSimilarityCalculator(this, cloner);
}
public static double CalculateSimilarity(PotvinEncoding left, PotvinEncoding right) {
if (left == null || right == null)
throw new ArgumentException("Cannot calculate similarity because one of the provided solutions or both are null.");
// extract edges from first solution
var edges1 = new List>();
foreach (Tour tour in left.Tours) {
edges1.Add(new Tuple(0, tour.Cities[0]));
for (int i = 0; i < tour.Cities.Count - 1; i++)
edges1.Add(new Tuple(tour.Cities[i], tour.Cities[i + 1]));
edges1.Add(new Tuple(tour.Cities[tour.Cities.Count - 1], 0));
}
// extract edges from second solution
var edges2 = new List>();
foreach (Tour tour in right.Tours) {
edges2.Add(new Tuple(0, tour.Cities[0]));
for (int i = 0; i < tour.Cities.Count - 1; i++)
edges2.Add(new Tuple(tour.Cities[i], tour.Cities[i + 1]));
edges2.Add(new Tuple(tour.Cities[tour.Cities.Count - 1], 0));
}
if (edges1.Count + edges2.Count == 0)
throw new ArgumentException("Cannot calculate diversity because no tours exist.");
int identicalEdges = 0;
foreach (var edge in edges1) {
if (edges2.Any(x => x.Equals(edge)))
identicalEdges++;
}
return identicalEdges * 2.0 / (edges1.Count + edges2.Count);
}
protected override double CalculateSimilarity(IScope left, IScope right) {
PotvinEncoding sol1 = left.Variables[Target].Value as PotvinEncoding;
PotvinEncoding sol2 = right.Variables[Target].Value as PotvinEncoding;
return CalculateSimilarity(sol1, sol2);
}
}
}