Examples of DBIDIter

de.lmu.ifi.dbs.elki.database.ids.DBIDIter

Iterator for DBIDs. Important note: this iterator has a significantly different syntax and semantics than the Java iterators. It is much more aligned with C than with Java, but at the same time, the syntax is much more compatible with for loops. Usage example:

{@code }for (DBIDIter iter = ids.iter(); iter.valid(); iter.advance()) iter.getDBID(); } }

We list some fundamental differences.

{@link DBIDIter#valid() iter.valid()} refers to the current element,{@code Iterator.next()} to the next.
{@link DBIDIter#advance() iter.advance()} does not return an element. Use{@code get...} to access it.
{@code DBIDIter.get...} do not advance the iterator.

@author Erich Schubert

   * @param distQ Distance query
   * @return Weight sum
   */
  protected double initialWeights(double[] weights, ArrayDBIDs ids, DBID latest, DistanceQuery<V, D> distQ) {
    double weightsum = 0.0;
    DBIDIter it = ids.iter();
    for(int i = 0; i < weights.length; i++, it.advance()) {
      DBID id = it.getDBID();
      if(latest.equals(id)) {
        weights[i] = 0.0;
      }
      else {
        double d = distQ.distance(latest, id).doubleValue();

   * @param distQ Distance query
   * @return Weight sum
   */
  protected double updateWeights(double[] weights, ArrayDBIDs ids, DBID latest, DistanceQuery<V, D> distQ) {
    double weightsum = 0.0;
    DBIDIter it = ids.iter();
    for(int i = 0; i < weights.length; i++, it.advance()) {
      DBID id = it.getDBID();
      if(weights[i] > 0.0) {
        double d = distQ.distance(latest, id).doubleValue();
        weights[i] = Math.min(weights[i], d * d);
        weightsum += weights[i];
      }

   * @return Weight sum
   */
  protected double updateWeights(double[] weights, ArrayDBIDs ids, DBID latest, PrimitiveDoubleDistanceFunction<V> distF, Relation<V> rel) {
    final V lv = rel.get(latest);
    double weightsum = 0.0;
    DBIDIter it = ids.iter();
    for(int i = 0; i < weights.length; i++, it.advance()) {
      DBID id = it.getDBID();
      if(weights[i] > 0.0) {
        double d = distF.doubleDistance(lv, rel.get(id));
        weights[i] = Math.min(weights[i], d * d);
        weightsum += weights[i];
      }

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Examples of DBIDIter

Examples of de.lmu.ifi.dbs.elki.database.ids.DBIDIter

Examples of de.lmu.ifi.dbs.elki.database.ids.DBIDIter

Examples of de.lmu.ifi.dbs.elki.database.ids.DBIDIter