Import Debian changes 0.4.1-1

elki (0.4.1-1) unstable; urgency=low

  * New upstream bug fix release (a couple of minor fixes)
  * Specify encoding UTF-8 for javac (Closes: #642659)

17 files changed, 149 insertions, 48 deletions

diff --git a/debian/changelog b/debian/changelog
index 1728b88f..93e85cf2 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,10 @@
+elki (0.4.1-1) unstable; urgency=low
+
+  * New upstream bug fix release (a couple of minor fixes)
+  * Specify encoding UTF-8 for javac (Closes: #642659)
+
+ -- Erich Schubert <erich@debian.org>  Mon, 30 Jan 2012 21:01:31 +0100
+
 elki (0.4.0-1) unstable; urgency=low
 
   * New upstream release. (0.4.0 final)
diff --git a/debian/patches/build.patch b/debian/patches/build.patch
index 9ac8e7e7..9bc8c024 100644
--- a/debian/patches/build.patch
+++ b/debian/patches/build.patch
@@ -1,17 +1,17 @@
-Index: elki-0.4.0~beta2/build.xml
+# Debian build.xml file
+Index: elki-0.4.1/build.xml
 ===================================================================
 --- /dev/null	1970-01-01 00:00:00.000000000 +0000
-+++ elki-0.4.0~beta2/build.xml	2011-09-03 01:54:38.000000000 +0200
-@@ -0,0 +1,58 @@
++++ elki-0.4.1/build.xml	2012-01-30 21:01:27.000000000 +0100
+@@ -0,0 +1,57 @@
 +<project name="ELKI" default="dist" basedir=".">
 +  <property name="src" location="src"/>
 +  <property name="build" location="build"/>
 +  <property name="dist" location="dist"/>
 +  <property name="elki" value="de.lmu.ifi.dbs.elki"/>
-+  <property name="title" value="ELKI: Environment for DeveLoping KDD-A
-+pplications Supported by Index-Structures"/>
++  <property name="title" value="ELKI: Environment for DeveLoping KDD-Applications Supported by Index-Structures"/>
 +  <property name="url" value="http://elki.dbs.ifi.lmu.de/"/>
-+  <property name="version" value="0.4.0~beta1"/>
++  <property name="version" value="0.4.1"/>
 +
 +  <target name="init">
 +    <!-- Create the build directory structure used by compile -->
@@ -20,7 +20,7 @@ Index: elki-0.4.0~beta2/build.xml
 +
 +  <target name="compile" depends="init">
 +    <!-- Compile the java code from ${src} into ${build} -->
-+    <javac destdir="${build}" includeantruntime="false" deprecation="false" debug="false" optimize="true" source="1.6" target="1.6" debuglevel="">
++    <javac destdir="${build}" includeantruntime="false" deprecation="false" debug="false" optimize="true" source="1.6" target="1.6" debuglevel="" encoding="UTF-8">
 +      <compilerarg value="-Xlint:all" />
 +      <classpath>
 +        <pathelement path="${src}" />
diff --git a/src/de/lmu/ifi/dbs/elki/algorithm/clustering/DeLiClu.java b/src/de/lmu/ifi/dbs/elki/algorithm/clustering/DeLiClu.java
index d4d6d20a..ca401ddc 100644
--- a/src/de/lmu/ifi/dbs/elki/algorithm/clustering/DeLiClu.java
+++ b/src/de/lmu/ifi/dbs/elki/algorithm/clustering/DeLiClu.java
@@ -153,7 +153,7 @@ public class DeLiClu<NV extends NumberVector<NV, ?>, D extends Distance<D>> exte
     clusterOrder.add(startID, null, distFunction.getDistanceFactory().infiniteDistance());
     int numHandled = 1;
     index.setHandled(startID, relation.get(startID));
-    SpatialDirectoryEntry rootEntry = (SpatialDirectoryEntry)index.getRootEntry();
+    SpatialDirectoryEntry rootEntry = (SpatialDirectoryEntry) index.getRootEntry();
     SpatialObjectPair spatialObjectPair = new SpatialObjectPair(distFunction.getDistanceFactory().nullDistance(), rootEntry, rootEntry, true);
     heap.add(spatialObjectPair);
 
@@ -217,8 +217,8 @@ public class DeLiClu<NV extends NumberVector<NV, ?>, D extends Distance<D>> exte
    * @param knns the knn list
    */
   private void expandNodes(DeLiCluTree index, SpatialPrimitiveDistanceFunction<NV, D> distFunction, SpatialObjectPair nodePair, DataStore<KNNList<D>> knns) {
-    DeLiCluNode node1 = index.getNode(((SpatialDirectoryEntry)nodePair.entry1).getPageID());
-    DeLiCluNode node2 = index.getNode(((SpatialDirectoryEntry)nodePair.entry2).getPageID());
+    DeLiCluNode node1 = index.getNode(((SpatialDirectoryEntry) nodePair.entry1).getPageID());
+    DeLiCluNode node2 = index.getNode(((SpatialDirectoryEntry) nodePair.entry2).getPageID());
 
     if(node1.isLeaf()) {
       expandLeafNodes(distFunction, node1, node2, knns);
@@ -238,6 +238,9 @@ public class DeLiClu<NV extends NumberVector<NV, ?>, D extends Distance<D>> exte
    * @param node2 the second node
    */
   private void expandDirNodes(SpatialPrimitiveDistanceFunction<NV, D> distFunction, DeLiCluNode node1, DeLiCluNode node2) {
+    if(logger.isDebuggingFinest()) {
+      logger.debugFinest("ExpandDirNodes: " + node1.getPageID() + " + " + node2.getPageID());
+    }
     int numEntries_1 = node1.getNumEntries();
     int numEntries_2 = node2.getNumEntries();
 
@@ -271,6 +274,9 @@ public class DeLiClu<NV extends NumberVector<NV, ?>, D extends Distance<D>> exte
    * @param knns the knn list
    */
   private void expandLeafNodes(SpatialPrimitiveDistanceFunction<NV, D> distFunction, DeLiCluNode node1, DeLiCluNode node2, DataStore<KNNList<D>> knns) {
+    if(logger.isDebuggingFinest()) {
+      logger.debugFinest("ExpandLeafNodes: " + node1.getPageID() + " + " + node2.getPageID());
+    }
     int numEntries_1 = node1.getNumEntries();
     int numEntries_2 = node2.getNumEntries();
 
@@ -304,7 +310,7 @@ public class DeLiClu<NV extends NumberVector<NV, ?>, D extends Distance<D>> exte
    * @param knns the knn list
    */
   private void reinsertExpanded(SpatialPrimitiveDistanceFunction<NV, D> distFunction, DeLiCluTree index, List<TreeIndexPathComponent<DeLiCluEntry>> path, DataStore<KNNList<D>> knns) {
-    SpatialDirectoryEntry rootEntry = (SpatialDirectoryEntry)path.remove(0).getEntry();
+    SpatialDirectoryEntry rootEntry = (SpatialDirectoryEntry) path.remove(0).getEntry();
     reinsertExpanded(distFunction, index, path, 0, rootEntry, knns);
   }
 
diff --git a/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNOutlier.java b/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNOutlier.java
index e8097518..fa89f954 100644
--- a/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNOutlier.java
+++ b/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNOutlier.java
@@ -40,6 +40,7 @@ import de.lmu.ifi.dbs.elki.distance.distancefunction.DistanceFunction;
 import de.lmu.ifi.dbs.elki.distance.distancevalue.NumberDistance;

 import de.lmu.ifi.dbs.elki.logging.Logging;

 import de.lmu.ifi.dbs.elki.logging.progress.FiniteProgress;

+import de.lmu.ifi.dbs.elki.math.DoubleMinMax;

 import de.lmu.ifi.dbs.elki.database.relation.MaterializedRelation;

 import de.lmu.ifi.dbs.elki.result.outlier.BasicOutlierScoreMeta;

 import de.lmu.ifi.dbs.elki.result.outlier.OutlierResult;

@@ -113,7 +114,7 @@ public class KNNOutlier<O, D extends NumberDistance<D, ?>> extends AbstractDista
     }

     FiniteProgress progressKNNDistance = logger.isVerbose() ? new FiniteProgress("kNN distance for objects", relation.size(), logger) : null;

 

-    double maxodegree = 0;

+    DoubleMinMax minmax = new DoubleMinMax();

     WritableDataStore<Double> knno_score = DataStoreUtil.makeStorage(relation.getDBIDs(), DataStoreFactory.HINT_STATIC, Double.class);

     // compute distance to the k nearest neighbor.

     for(DBID id : distanceQuery.getRelation().iterDBIDs()) {

@@ -124,7 +125,7 @@ public class KNNOutlier<O, D extends NumberDistance<D, ?>> extends AbstractDista
       double dkn = knns.get(last).getDistance().doubleValue();

       knno_score.put(id, dkn);

 

-      maxodegree = Math.max(maxodegree, dkn);

+      minmax.put(dkn);

 

       if(progressKNNDistance != null) {

         progressKNNDistance.incrementProcessed(logger);

@@ -134,7 +135,7 @@ public class KNNOutlier<O, D extends NumberDistance<D, ?>> extends AbstractDista
       progressKNNDistance.ensureCompleted(logger);

     }

     Relation<Double> scoreres = new MaterializedRelation<Double>("kNN Outlier Score", "knn-outlier", TypeUtil.DOUBLE, knno_score, relation.getDBIDs());

-    OutlierScoreMeta meta = new BasicOutlierScoreMeta(Double.NaN, maxodegree, 0.0, Double.POSITIVE_INFINITY);

+    OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0.0);

     return new OutlierResult(meta, scoreres);

   }

 

diff --git a/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNWeightOutlier.java b/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNWeightOutlier.java
index 17292a9f..02e0789b 100644
--- a/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNWeightOutlier.java
+++ b/src/de/lmu/ifi/dbs/elki/algorithm/outlier/KNNWeightOutlier.java
@@ -40,6 +40,7 @@ import de.lmu.ifi.dbs.elki.distance.distancefunction.DistanceFunction;
 import de.lmu.ifi.dbs.elki.distance.distancevalue.NumberDistance;

 import de.lmu.ifi.dbs.elki.logging.Logging;

 import de.lmu.ifi.dbs.elki.logging.progress.FiniteProgress;

+import de.lmu.ifi.dbs.elki.math.DoubleMinMax;

 import de.lmu.ifi.dbs.elki.database.relation.MaterializedRelation;

 import de.lmu.ifi.dbs.elki.result.outlier.BasicOutlierScoreMeta;

 import de.lmu.ifi.dbs.elki.result.outlier.OutlierResult;

@@ -113,7 +114,7 @@ public class KNNWeightOutlier<O, D extends NumberDistance<D, ?>> extends Abstrac
     }

     FiniteProgress progressKNNWeight = logger.isVerbose() ? new FiniteProgress("KNNWOD_KNNWEIGHT for objects", relation.size(), logger) : null;

 

-    double maxweight = 0;

+    DoubleMinMax minmax = new DoubleMinMax();

 

     // compute distance to the k nearest neighbor. n objects with the highest

     // distance are flagged as outliers

@@ -130,7 +131,7 @@ public class KNNWeightOutlier<O, D extends NumberDistance<D, ?>> extends Abstrac
 

       double doubleSkn = skn.getValue().doubleValue();

       knnw_score.put(id, doubleSkn);

-      maxweight = Math.max(maxweight, doubleSkn);

+      minmax.put(doubleSkn);

 

       if(progressKNNWeight != null) {

         progressKNNWeight.incrementProcessed(logger);

@@ -141,7 +142,7 @@ public class KNNWeightOutlier<O, D extends NumberDistance<D, ?>> extends Abstrac
     }

 

     Relation<Double> res = new MaterializedRelation<Double>("Weighted kNN Outlier Score", "knnw-outlier", TypeUtil.DOUBLE, knnw_score, relation.getDBIDs());

-    OutlierScoreMeta meta = new BasicOutlierScoreMeta(Double.NaN, maxweight, 0.0, Double.POSITIVE_INFINITY);

+    OutlierScoreMeta meta = new BasicOutlierScoreMeta(minmax.getMin(), minmax.getMax(), 0.0, Double.POSITIVE_INFINITY, 0.0);

     return new OutlierResult(meta, res);

   }

 

diff --git a/src/de/lmu/ifi/dbs/elki/database/StaticArrayDatabase.java b/src/de/lmu/ifi/dbs/elki/database/StaticArrayDatabase.java
index 4679cc52..9d96a55f 100644
--- a/src/de/lmu/ifi/dbs/elki/database/StaticArrayDatabase.java
+++ b/src/de/lmu/ifi/dbs/elki/database/StaticArrayDatabase.java
@@ -143,6 +143,7 @@ public class StaticArrayDatabase extends AbstractDatabase implements Database, P
       // TODO: this is an ugly hack
       this.idrep = new DBIDView(this, this.ids);
       relations.add(this.idrep);
+      getHierarchy().add(this, idrep);
 
       // insert into db - note: DBIDs should have been prepared before this!
       Relation<?>[] targets = alignColumns(objpackages);
diff --git a/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java b/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java
index e0437869..6e90af51 100644
--- a/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java
+++ b/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java
@@ -79,7 +79,7 @@ public class RandomDoubleVectorDatabaseConnection extends AbstractDatabaseConnec
   
   @Override
   public MultipleObjectsBundle loadData() {
-    VectorFieldTypeInformation<DoubleVector> type = VectorFieldTypeInformation.get(DoubleVector.class, dim);
+    VectorFieldTypeInformation<DoubleVector> type = new VectorFieldTypeInformation(DoubleVector.class, dim, new DoubleVector(new double[dim]));
     List<DoubleVector> vectors = new ArrayList<DoubleVector>(size);
 
     // Setup random generator
@@ -178,4 +178,4 @@ public class RandomDoubleVectorDatabaseConnection extends AbstractDatabaseConnec
       return new RandomDoubleVectorDatabaseConnection(dim, size, seed, filters);
     }
   }
-}
\ No newline at end of file
+}
diff --git a/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java.rej b/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java.rej
new file mode 100644
index 00000000..d339c8ee
--- /dev/null
+++ b/src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java.rej
@@ -0,0 +1,14 @@
+--- src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java	(Revision 8763)
++++ src/de/lmu/ifi/dbs/elki/datasource/RandomDoubleVectorDatabaseConnection.java	(Revision 8764)
+@@ -76,10 +76,9 @@
+ 
+   private static final Logging logger = Logging.getLogger(RandomDoubleVectorDatabaseConnection.class);
+ 
+-  
+   @Override
+   public MultipleObjectsBundle loadData() {
+-    VectorFieldTypeInformation<DoubleVector> type = new VectorFieldTypeInformation<DoubleVector>(DoubleVector.class, DoubleVector.STATIC, dim);
++    VectorFieldTypeInformation<DoubleVector> type = new VectorFieldTypeInformation<DoubleVector>(DoubleVector.class, dim, DoubleVector.STATIC);
+     List<DoubleVector> vectors = new ArrayList<DoubleVector>(size);
+ 
+     // Setup random generator
diff --git a/src/de/lmu/ifi/dbs/elki/evaluation/roc/ROC.java b/src/de/lmu/ifi/dbs/elki/evaluation/roc/ROC.java
index 9716a586..1b37bfff 100644
--- a/src/de/lmu/ifi/dbs/elki/evaluation/roc/ROC.java
+++ b/src/de/lmu/ifi/dbs/elki/evaluation/roc/ROC.java
@@ -81,8 +81,6 @@ public class ROC {
    * @return area under curve
    */
   public static <C extends Comparable<? super C>, T> List<DoubleDoublePair> materializeROC(int size, Set<? super T> ids, Iterator<? extends PairInterface<C, T>> nei) {
-    final double DELTA = 0.01 / (size * size);
-
     int postot = ids.size();
     int negtot = size - postot;
     int poscnt = 0;
@@ -116,18 +114,23 @@ public class ROC {
       if(res.size() >= 2) {
         DoubleDoublePair last1 = res.get(res.size() - 2);
         DoubleDoublePair last2 = res.get(res.size() - 1);
+        final double ldx = last2.first - last1.first;
+        final double cdx = curneg - last2.first;
+        final double ldy = last2.second - last1.second;
+        final double cdy = curpos - last2.second;
         // vertical simplification
-        if((last1.first == last2.first) && (last2.first == curneg)) {
+        if((ldx == 0) && (cdx == 0)) {
           res.remove(res.size() - 1);
         }
         // horizontal simplification
-        else if((last1.second == last2.second) && (last2.second == curpos)) {
+        else if((ldy == 0) && (cdy == 0)) {
           res.remove(res.size() - 1);
         }
         // diagonal simplification
-        // TODO: Make a test.
-        else if(Math.abs((last2.first - last1.first) - (curneg - last2.first)) < DELTA && Math.abs((last2.second - last1.second) - (curpos - last2.second)) < DELTA) {
-          res.remove(res.size() - 1);
+        else if(ldy > 0 && cdy > 0) {
+          if(Math.abs((ldx / ldy) - (cdx / cdy)) < 1E-10) {
+            res.remove(res.size() - 1);
+          }
         }
       }
       // Add a new point (for the previous entry!)
@@ -135,7 +138,8 @@ public class ROC {
       prev = cur;
     }
     // ensure we end up in the top right corner.
-    // Since we didn't add a point for the last entry yet, this likely is needed.
+    // Since we didn't add a point for the last entry yet, this likely is
+    // needed.
     {
       DoubleDoublePair last = res.get(res.size() - 1);
       if(last.first < 1.0 || last.second < 1.0) {
diff --git a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/AbstractRStarTree.java b/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/AbstractRStarTree.java
index 9e76b474..4fafe1bb 100644
--- a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/AbstractRStarTree.java
+++ b/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/AbstractRStarTree.java
@@ -156,7 +156,7 @@ public abstract class AbstractRStarTree<N extends AbstractRStarTreeNode<N, E>, E
     N node = getNode(subtree.getLastPathComponent().getEntry());
     if(node.isLeaf()) {
       for(int i = 0; i < node.getNumEntries(); i++) {
-        if(((LeafEntry) node.getEntry(i)).getDBID() == id) {
+        if(((LeafEntry) node.getEntry(i)).getDBID().equals(id)) {
           return subtree.pathByAddingChild(new TreeIndexPathComponent<E>(node.getEntry(i), i));
         }
       }
diff --git a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/deliclu/DeLiCluTreeIndex.java b/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/deliclu/DeLiCluTreeIndex.java
index 9bf6be8f..062ddfb2 100644
--- a/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/deliclu/DeLiCluTreeIndex.java
+++ b/src/de/lmu/ifi/dbs/elki/index/tree/spatial/rstarvariants/deliclu/DeLiCluTreeIndex.java
@@ -44,6 +44,7 @@ import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.query.RStarTreeUtil;
 import de.lmu.ifi.dbs.elki.index.tree.spatial.rstarvariants.util.InsertionStrategy;
 import de.lmu.ifi.dbs.elki.logging.Logging;
 import de.lmu.ifi.dbs.elki.persistent.PageFile;
+import de.lmu.ifi.dbs.elki.utilities.exceptions.AbortException;
 
 /**
  * The common use of the DeLiClu tree: indexing number vectors.
@@ -103,7 +104,7 @@ public class DeLiCluTreeIndex<O extends NumberVector<?, ?>> extends DeLiCluTree
     IndexTreePath<DeLiCluEntry> pathToObject = findPathToObject(getRootPath(), obj, id);
 
     if(pathToObject == null) {
-      return null;
+      throw new AbortException("Object not found in setHandled.");
     }
 
     // set o handled
diff --git a/src/de/lmu/ifi/dbs/elki/math/ConvexHull2D.java b/src/de/lmu/ifi/dbs/elki/math/ConvexHull2D.java
index 3317e500..10a27f38 100644
--- a/src/de/lmu/ifi/dbs/elki/math/ConvexHull2D.java
+++ b/src/de/lmu/ifi/dbs/elki/math/ConvexHull2D.java
@@ -83,6 +83,7 @@ public class ConvexHull2D {
   public void add(Vector point) {

     if (this.ok) {

       this.points = new LinkedList<Vector>(this.points);

+      this.ok = false;

     }

     this.points.add(point);

     // Update data set extends

@@ -115,7 +116,7 @@ public class ConvexHull2D {
     Collections.sort(this.points, new Comparator<Vector>() {

       @Override

       public int compare(Vector o1, Vector o2) {

-        return isLeft(o1, o2, origin) ? +1 : 0;

+        return isLeft(o1, o2, origin) ? +1 : -1;

       }

     });

 

@@ -125,7 +126,7 @@ public class ConvexHull2D {
 

   /**

    * Find the starting point, and sort it to the beginning of the list. The

-   * starting point must be on the outer hull. Any "skyline" point will do, e.g.

+   * starting point must be on the outer hull. Any "most extreme" point will do, e.g.

    * the one with the lowest Y coordinate and for ties with the lowest X.

    */

   private void findStartingPoint() {

diff --git a/src/de/lmu/ifi/dbs/elki/math/MathUtil.java b/src/de/lmu/ifi/dbs/elki/math/MathUtil.java
index 6856a44b..83fbca92 100644
--- a/src/de/lmu/ifi/dbs/elki/math/MathUtil.java
+++ b/src/de/lmu/ifi/dbs/elki/math/MathUtil.java
@@ -244,12 +244,13 @@ public final class MathUtil {
       double meanX = x[0];
       double meanY = y[0];
       for(int i = 1; i < xdim; i++) {
+        int sumWe = i + 1;
         // Delta to previous mean
         final double deltaX = x[i] - meanX;
         final double deltaY = y[i] - meanY;
         // Update means
-        meanX += deltaX / i;
-        meanY += deltaY / i;
+        meanX += deltaX / sumWe;
+        meanY += deltaY / sumWe;
         // Delta to new mean
         final double neltaX = x[i] - meanX;
         final double neltaY = y[i] - meanY;
diff --git a/src/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/StandardDeviationScaling.java b/src/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/StandardDeviationScaling.java
index 62223730..10db8e56 100644
--- a/src/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/StandardDeviationScaling.java
+++ b/src/de/lmu/ifi/dbs/elki/utilities/scaling/outlier/StandardDeviationScaling.java
@@ -122,6 +122,9 @@ public class StandardDeviationScaling implements OutlierScalingFunction {
       }
       mean = mv.getMean();
       factor = lambda * mv.getSampleStddev() * MathUtil.SQRT2;
+      if (factor == 0.0) {
+        factor = Double.MIN_NORMAL;
+      }
     }
     else {
       mean = fixedmean;
@@ -135,6 +138,9 @@ public class StandardDeviationScaling implements OutlierScalingFunction {
         }
       }
       factor = lambda * Math.sqrt(sqsum / cnt) * MathUtil.SQRT2;
+      if (factor == 0.0) {
+        factor = Double.MIN_NORMAL;
+      }
     }
   }
 
diff --git a/src/de/lmu/ifi/dbs/elki/visualization/VisualizationTask.java b/src/de/lmu/ifi/dbs/elki/visualization/VisualizationTask.java
index 04d2c5eb..3cf05e37 100644
--- a/src/de/lmu/ifi/dbs/elki/visualization/VisualizationTask.java
+++ b/src/de/lmu/ifi/dbs/elki/visualization/VisualizationTask.java
@@ -324,7 +324,7 @@ public class VisualizationTask extends AnyMap<String> implements Cloneable, Resu
     Integer level1 = this.get(VisualizationTask.META_LEVEL, Integer.class);
     Integer level2 = other.get(VisualizationTask.META_LEVEL, Integer.class);
     if(level1 != null && level2 != null && level1 != level2) {
-      return level1 - level2;
+      return level2 - level1;
     }
     // sort by name otherwise.
     String name1 = this.getShortName();
diff --git a/src/de/lmu/ifi/dbs/elki/visualization/gui/overview/RectangleArranger.java b/src/de/lmu/ifi/dbs/elki/visualization/gui/overview/RectangleArranger.java
index ad87c3fc..505e61d8 100644
--- a/src/de/lmu/ifi/dbs/elki/visualization/gui/overview/RectangleArranger.java
+++ b/src/de/lmu/ifi/dbs/elki/visualization/gui/overview/RectangleArranger.java
@@ -252,18 +252,6 @@ public class RectangleArranger<T> {
       assert assertConsistent();
     }
     logger.debugFinest("Best: " + bestsx + "," + bestsy + " - " + bestex + "," + bestey + " inc: " + bestwi + "x" + besthi + " " + bestinc);
-    // Need to split a column.
-    // TODO: find best column to split. Currently: last
-    if(bestwi < 0) {
-      splitCol(bestex, -bestwi);
-      bestwi = 0.0;
-    }
-    // Need to split a row.
-    // TODO: find best row to split. Currently: last
-    if(besthi < 0) {
-      splitRow(bestey, -besthi);
-      besthi = 0.0;
-    }
     // Need to increase the total area
     if(bestinc > 0) {
       assert (bestex == cols - 1 || bestey == rows - 1);
@@ -274,6 +262,18 @@ public class RectangleArranger<T> {
       put(w, h, data);
       return;
     }
+    // Need to split a column.
+    // TODO: find best column to split. Currently: last
+    if(bestwi < 0.0) {
+      splitCol(bestex, -bestwi);
+      bestwi = 0.0;
+    }
+    // Need to split a row.
+    // TODO: find best row to split. Currently: last
+    if(besthi < 0.0) {
+      splitRow(bestey, -besthi);
+      besthi = 0.0;
+    }
     for(int x = bestsx; x <= bestex; x++) {
       for(int y = bestsy; y <= bestey; y++) {
         usage.get(y).set(x, data);
@@ -371,7 +371,7 @@ public class RectangleArranger<T> {
     {
       double wsum = 0.0;
       for(int x = 0; x < cols; x++) {
-        assert (widths.get(x) > 0);
+        assert (widths.get(x) > 0) : "Negative width: "+widths.get(x);
         wsum += widths.get(x);
       }
       assert (Math.abs(wsum - twidth) < 1E-10);
@@ -379,7 +379,7 @@ public class RectangleArranger<T> {
     {
       double hsum = 0.0;
       for(int y = 0; y < rows; y++) {
-        assert (heights.get(y) > 0);
+        assert (heights.get(y) > 0) : "Negative height: "+heights.get(y);
         hsum += heights.get(y);
       }
       assert (Math.abs(hsum - theight) < 1E-10);
diff --git a/test/de/lmu/ifi/dbs/elki/math/TestMathUtil.java b/test/de/lmu/ifi/dbs/elki/math/TestMathUtil.java
new file mode 100644
index 00000000..16dfe77c
--- /dev/null
+++ b/test/de/lmu/ifi/dbs/elki/math/TestMathUtil.java
@@ -0,0 +1,58 @@
+package de.lmu.ifi.dbs.elki.math;
+
+import static org.junit.Assert.*;
+
+import java.util.Random;
+
+import org.junit.Test;
+
+import de.lmu.ifi.dbs.elki.JUnit4Test;
+/*
+ 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/>.
+ */
+
+public class TestMathUtil implements JUnit4Test {
+
+  @Test
+  public void testPearsonCorrelation() {
+    final int size = 1000;
+    final long seed = 1;
+    double[] data1 = new double[size];
+    double[] data2 = new double[size];
+    double[] weight1 = new double[size];
+    double[] weight2 = new double[size];
+
+    Random r = new Random(seed);
+    for (int i = 0; i < size; i++) {
+      data1[i] = r.nextDouble();
+      data2[i] = r.nextDouble();
+      weight1[i] = 1.0;
+      weight2[i] = 0.1;
+    }
+    
+    double pear = MathUtil.pearsonCorrelationCoefficient(data1, data2);
+    double wpear1 = MathUtil.weightedPearsonCorrelationCoefficient(data1, data2, weight1);
+    double wpear2 = MathUtil.weightedPearsonCorrelationCoefficient(data1, data2, weight2);
+    assertEquals("Pearson and weighted pearson should be the same with constant weights.", pear, wpear1, 1E-10);
+    assertEquals("Weighted pearsons should be the same with constant weights.", wpear1, wpear2, 1E-10);
+  }
+}