Changeset 11293 for branches/HeuristicLab.Problems.Orienteering

Timestamp:

08/20/14 13:23:50 (10 years ago)

Author:

pfleck

Message:

#2208
Changed selection of neighborhood for shaking operator to a deterministic selection.
This way, neighborhoods won't be visited multiple times during an attempt to escape local optimum.

File:

• branches/HeuristicLab.Problems.Orienteering/HeuristicLab.Problems.Orienteering/3.3/Shakers/OrienteeringShakingOperator.cs (modified) (1 diff)

branches/HeuristicLab.Problems.Orienteering/HeuristicLab.Problems.Orienteering/3.3/Shakers/OrienteeringShakingOperator.cs

@@ -128 +128 @@
       if (initialTour.Length > 2) {
         // Limit the neighborhood to the tour length
-        int maxNeighborhood = CurrentNeighborhoodIndexParameter.ActualValue.Value + 1;
-        int limit = initialTour.Length - 2; // neighborhood limit within [0, changable tour length - 1)
-        int neighborhood = random.Next((limit > maxNeighborhood) ? maxNeighborhood : limit) + 1;
+        int currentNeighborhood = CurrentNeighborhoodIndexParameter.ActualValue.Value + 1;
+        int maximumNeighborhood = initialTour.Length - 2; // neighborhood limit within [0, changable tour length - 1)
+        maximumNeighborhood = (maximumNeighborhood > currentNeighborhood) ? currentNeighborhood : maximumNeighborhood;
+        int neighborhood = maximumNeighborhood;//random.Next(maximumNeighborhood) + 1;
 
         // Find all points that are not yet included in the tour and are