Minor bug fixes and improvements

TULIP/src/lu/list/itis/dkd/tui/feature/cluster/clusterer/DBScanClusterer.java

@@ -148,10 +148,12 @@ public class DBScanClusterer<T extends Positionable> implements Clusterer<T> {
         int numberOfPoints = points.size();
         for (int current = 0; current < numberOfPoints; current++) {
             int assignedCLusterId = this.clusterIds.get(current);
-            Cluster<T> cluster = clustered.get(assignedCLusterId);
-            cluster.setHandleId(assignedCLusterId);
-            cluster.addPoint(this.points.get(current));
-            clustered.set(assignedCLusterId, cluster);
+            if (assignedCLusterId >= 0) {
+                Cluster<T> cluster = clustered.get(assignedCLusterId);
+                cluster.setHandleId(assignedCLusterId);
+                cluster.addPoint(this.points.get(current));
+                clustered.set(assignedCLusterId, cluster);
+            }
         }
         return clustered;
     }

TULIP/src/lu/list/itis/dkd/tui/utility/Point.java

@@ -70,6 +70,8 @@ public class Point extends Float implements Comparable<Point>, Scriptable {
 
     private static final Logger LOGGER = LoggerFactory.getLogger(Point.class.getSimpleName());
 
+    private static final String NO_SUCH_AXIS_MESSAGE = "This should never happen! No such axis {}!";
+
 
     /** Constant identifying the X Axis */
     public static final int X_AXIS = 0;
@@ -562,7 +564,14 @@ public class Point extends Float implements Comparable<Point>, Scriptable {
         return (deltaX * deltaX) + (deltaY * deltaY);
     }
 
-    /** {@inheritDoc} */
+    /**
+     * returns the distance between this point and the other one along a given axis. Method returns
+     * the absolute value of the distance
+     * 
+     * @param other
+     * @param axis
+     * @return
+     */
     public double getDistance(Point other, int axis) {
         double distance = 0;
         switch (axis) {
@@ -573,10 +582,27 @@ public class Point extends Float implements Comparable<Point>, Scriptable {
                 distance = this.y - other.y;
                 break;
             default:
-                LOGGER.error("This should never happen! No such axis {}!", axis); //$NON-NLS-1$
+                LOGGER.error(NO_SUCH_AXIS_MESSAGE, axis);
+                break;
+        }
+        return Math.abs(distance);
+    }
+
+    /** {@inheritDoc} */
+    public double getSquaredDistance(Point other, int axis) {
+        double distance = 0;
+        switch (axis) {
+            case X_AXIS:
+                distance = this.x - other.x;
+                break;
+            case Y_AXIS:
+                distance = this.y - other.y;
+                break;
+            default:
+                LOGGER.error(NO_SUCH_AXIS_MESSAGE, axis);
                 break;
         }
-        return Math.sqrt(distance * distance);
+        return (distance * distance);
     }
 
     /** {@inheritDoc} */
@@ -630,7 +656,7 @@ public class Point extends Float implements Comparable<Point>, Scriptable {
                     comparison = PointComparator.y.compare(this, o);
                     break;
                 default:
-                    LOGGER.error("This should never happen! No such axis {}!", axis); //$NON-NLS-1$
+                    LOGGER.error(NO_SUCH_AXIS_MESSAGE, axis);
                     break;
             }
         }

TULIP/src/lu/list/itis/dkd/tui/utility/kdtree/SquaredDistancePointComparator.java

@@ -40,7 +40,7 @@ public class SquaredDistancePointComparator implements KdComparator<Point> {
     /** {@inheritDoc} */
     @Override
     public double getDistance(Point o1, Point o2, int axis) {
-        return o1.getDistance(o2, axis);
+        return o1.getSquaredDistance(o2, axis);
     }
 
 }