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diff --git a/src/de/lmu/ifi/dbs/elki/index/tree/metrical/mtreevariants/split/MLBDistSplit.java b/src/de/lmu/ifi/dbs/elki/index/tree/metrical/mtreevariants/split/MLBDistSplit.java
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+++ b/src/de/lmu/ifi/dbs/elki/index/tree/metrical/mtreevariants/split/MLBDistSplit.java
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+package de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.split;
+/*
+This file is part of ELKI:
+Environment for Developing KDD-Applications Supported by Index-Structures
+
+Copyright (C) 2011
+Ludwig-Maximilians-Universität München
+Lehr- und Forschungseinheit für Datenbanksysteme
+ELKI Development Team
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program 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 Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import de.lmu.ifi.dbs.elki.database.ids.DBID;
+import de.lmu.ifi.dbs.elki.database.query.distance.DistanceQuery;
+import de.lmu.ifi.dbs.elki.distance.distancevalue.Distance;
+import de.lmu.ifi.dbs.elki.index.tree.DistanceEntry;
+import de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.AbstractMTreeNode;
+import de.lmu.ifi.dbs.elki.index.tree.metrical.mtreevariants.MTreeEntry;
+
+/**
+ * Encapsulates the required methods for a split of a node in an M-Tree. The
+ * routing objects are chosen according to the M_LB_DIST strategy.
+ * 
+ * @author Elke Achtert
+ * @param <O> the type of DatabaseObject to be stored in the M-Tree
+ * @param <D> the type of Distance used in the M-Tree
+ * @param <N> the type of AbstractMTreeNode used in the M-Tree
+ * @param <E> the type of MetricalEntry used in the M-Tree
+ */
+public class MLBDistSplit<O, D extends Distance<D>, N extends AbstractMTreeNode<O, D, N, E>, E extends MTreeEntry<D>> extends MTreeSplit<O, D, N, E> {
+  /**
+   * Creates a new split object.
+   * 
+   * @param node the node to be split
+   * @param distanceFunction the distance function
+   */
+  public MLBDistSplit(N node, DistanceQuery<O, D> distanceFunction) {
+    super();
+    promote(node, distanceFunction);
+  }
+
+  /**
+   * Selects the second object of the specified node to be promoted and stored
+   * into the parent node and partitions the entries according to the M_LB_DIST
+   * strategy.
+   * <p/>
+   * This strategy considers all possible pairs of objects and chooses the pair
+   * of objects for which the distance is maximum.
+   * 
+   * @param node the node to be split
+   * @param distanceFunction the distance function
+   */
+  private void promote(N node, DistanceQuery<O, D> distanceFunction) {
+    DBID firstPromoted = null;
+    DBID secondPromoted = null;
+
+    // choose first and second routing object
+    D currentMaxDist = distanceFunction.nullDistance();
+    for(int i = 0; i < node.getNumEntries(); i++) {
+      DBID id1 = node.getEntry(i).getRoutingObjectID();
+      for(int j = i + 1; j < node.getNumEntries(); j++) {
+        DBID id2 = node.getEntry(j).getRoutingObjectID();
+
+        D distance = distanceFunction.distance(id1, id2);
+        if(distance.compareTo(currentMaxDist) >= 0) {
+          firstPromoted = id1;
+          secondPromoted = id2;
+          currentMaxDist = distance;
+        }
+      }
+    }
+
+    // partition the entries
+    List<DistanceEntry<D, E>> list1 = new ArrayList<DistanceEntry<D, E>>();
+    List<DistanceEntry<D, E>> list2 = new ArrayList<DistanceEntry<D, E>>();
+    for(int i = 0; i < node.getNumEntries(); i++) {
+      DBID id = node.getEntry(i).getRoutingObjectID();
+      D d1 = distanceFunction.distance(firstPromoted, id);
+      D d2 = distanceFunction.distance(secondPromoted, id);
+
+      list1.add(new DistanceEntry<D, E>(node.getEntry(i), d1, i));
+      list2.add(new DistanceEntry<D, E>(node.getEntry(i), d2, i));
+    }
+    Collections.sort(list1);
+    Collections.sort(list2);
+
+    assignments = balancedPartition(node, firstPromoted, secondPromoted, distanceFunction);
+  }
+}