title: How to use ELKI for DBSCAN with precomputed distance matrix
body: <p>I've a precomputed distance matrix for all the points in my database.
  I'm trying to invoke ELKI gui with following command:</p>
  
  <pre><code>            /usr/share/java/elki.jar 
              -dbc.in xml_files.1000 
              -dbc.filter FixedDBIDsFilter 
              -dbc.startid 0 
              -algorithm clustering.DBSCAN 
              -algorithm.distancefunction external.FileBasedDoubleDistanceFunction 
              -distance.matrix Distance.txt 
              -dbscan.epsilon 1 
              -dbscan.minpts 10
  </code></pre>
  
  <p>But I keep getting following error message :</p>
  
  <p>Wrong parameter format! Parameter "dbscan.epsilon" requires a distance value, but the distance was not set!</p>
  
  <p>I can't figure out what am I doing wrong here...</p>