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diff --git a/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/AbstractDimensionsSelectingDistanceFunction.java b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/AbstractDimensionsSelectingDistanceFunction.java
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+++ b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/AbstractDimensionsSelectingDistanceFunction.java
@@ -0,0 +1,127 @@
+package de.lmu.ifi.dbs.elki.distance.distancefunction.subspace;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2014
+ 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/>.
+ */
+
+import java.util.List;
+
+import de.lmu.ifi.dbs.elki.data.FeatureVector;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractPrimitiveDistanceFunction;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.PrimitiveDistanceFunction;
+import de.lmu.ifi.dbs.elki.utilities.BitsUtil;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.constraints.CommonConstraints;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.IntListParameter;
+
+/**
+ * Abstract base class for distances computed only in subspaces.
+ * 
+ * Selected dimensions are encuded as bits in a {@code long[]}.
+ * 
+ * @author Elke Achtert
+ * @param <V> the type of FeatureVector to compute the distances in between
+ */
+public abstract class AbstractDimensionsSelectingDistanceFunction<V extends FeatureVector<?>> extends AbstractPrimitiveDistanceFunction<V> implements PrimitiveDistanceFunction<V>, DimensionSelectingSubspaceDistanceFunction<V> {
+  /**
+   * The dimensions to be considered for distance computation.
+   */
+  protected long[] dimensions;
+
+  /**
+   * Constructor.
+   * 
+   * @param dimensions
+   */
+  public AbstractDimensionsSelectingDistanceFunction(long[] dimensions) {
+    super();
+    this.dimensions = dimensions;
+  }
+
+  @Override
+  public double distance(V o1, V o2) {
+    return distance(o1, o2);
+  }
+
+  @Override
+  public long[] getSelectedDimensions() {
+    return dimensions;
+  }
+
+  @Override
+  public void setSelectedDimensions(long[] dimensions) {
+    if(this.dimensions == null || this.dimensions.length < dimensions.length) {
+      this.dimensions = dimensions.clone();
+      return;
+    }
+    BitsUtil.zeroI(this.dimensions);
+    BitsUtil.orI(this.dimensions, dimensions);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if(obj == null) {
+      return false;
+    }
+    if(!this.getClass().equals(obj.getClass())) {
+      return false;
+    }
+    return this.dimensions.equals(((AbstractDimensionsSelectingDistanceFunction<?>) obj).dimensions);
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public abstract static class Parameterizer extends AbstractParameterizer {
+    /**
+     * Dimensions parameter.
+     */
+    public static final OptionID DIMS_ID = new OptionID("distance.dims", "a comma separated array of integer values, where 0 <= d_i < the dimensionality of the feature space specifying the dimensions to be considered for distance computation. If this parameter is not set, no dimensions will be considered, i.e. the distance between two objects is always 0.");
+
+    protected long[] dimensions = null;
+
+    @Override
+    protected void makeOptions(Parameterization config) {
+      super.makeOptions(config);
+      final IntListParameter dimsP = new IntListParameter(DIMS_ID)//
+      .addConstraint(CommonConstraints.GREATER_EQUAL_ZERO_INT_LIST) //
+      .setOptional(true);
+      if(config.grab(dimsP)) {
+        final List<Integer> value = dimsP.getValue();
+        int maxd = 0;
+        for(int d : value) {
+          maxd = (d > maxd) ? d : maxd;
+        }
+        dimensions = BitsUtil.zero(maxd);
+        for(int d : value) {
+          BitsUtil.setI(dimensions, d);
+        }
+      }
+    }
+  }
+}