diff -N ZvTrack.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ ZvTrack.java	9 Oct 2006 17:25:27 -0000	1.1
@@ -0,0 +1,24 @@

+/**
+ * @version $Id: ZvTrack.java,v 1.1 2006/10/09 17:25:27 jstrube Exp $
+ */
+package org.lcsim.contrib.JanStrube.zvtop;
+
+import org.lcsim.contrib.JanStrube.tracking.NewTrack;
+import org.lcsim.contrib.JanStrube.tracking.Track;
+import org.lcsim.spacegeom.SpacePoint;
+
+/**
+ * @author jstrube
+ *
+ */
+public class ZvTrack {
+    /**
+     * returns the probability that a track goes through a certain point
+     * Assuming gaussian errors.
+     * After Lyons, p. 47
+     */
+    public static double getProbability(Track t, SpacePoint l) {
+        throw new RuntimeException("Not implemented");
+//        return 0;
+    }
+}

diff -N ZvMaximumMatrix.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ ZvMaximumMatrix.java	9 Oct 2006 17:25:27 -0000	1.1
@@ -0,0 +1,72 @@

+package org.lcsim.contrib.JanStrube.zvtop;
+
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.Set;
+import java.util.SortedMap;
+import java.util.TreeMap;
+import java.util.Map.Entry;
+
+/**
+ * Container of ZvMaxima
+ * This enables for the ZvMaxima to be sorted by V(r)
+ * while they still can be accessed by index (i, j) 
+ * @author jstrube
+ * @version $Id: ZvMaximumMatrix.java,v 1.1 2006/10/09 17:25:27 jstrube Exp $
+ *
+ */
+class ZvMaximumMatrix implements Iterable {
+
+    private class MatrixIndex {
+        MatrixIndex(int i, int j) {
+            _i = i;
+            _j = j;
+        }
+        int _i;
+        int _j;
+    }
+    SortedMap<ZvMaximum, MatrixIndex> _table; 
+       
+    /**
+     * 
+     */
+    ZvMaximumMatrix(Comparator comp) {
+        _table = new TreeMap<ZvMaximum, MatrixIndex>(comp);
+    }
+    
+    void add(ZvMaximum max, int i, int j) {
+        _table.put(max, new MatrixIndex(i, j));
+    }
+
+    /* (non-Javadoc)
+     * @see java.lang.Iterable#iterator()
+     */
+    public Iterator iterator() {
+        return _table.keySet().iterator();
+    }
+    
+    /**
+     * Accessor of ZvMaximum by indices of the constituent tracks in the list
+     * @param i index of the first Track
+     * @param j index of the second Track
+     * @return the ZvMaximum
+     */
+    ZvMaximum get(int i, int j) throws IllegalAccessException {
+        // Slow Access - OK, because primary access is by order in V(r)
+        Set<Entry<ZvMaximum, MatrixIndex>> entries = _table.entrySet();
+        for (Entry<ZvMaximum, MatrixIndex> entry  : entries) {
+            MatrixIndex index = entry.getValue();
+            // Symmetry in indices
+            if ((index._i == i && index._j == j)
+                    || (index._i == j && index._j == i) ) {
+                return entry.getKey();
+            }
+        }
+        throw new IllegalAccessException("ZvMaximumMatrix.get: index not found");
+    }
+    
+    Set<ZvMaximum> getMaxima() {
+        return _table.keySet();
+    }
+
+}