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diff --git a/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/OnedimensionalDistanceFunction.java b/src/de/lmu/ifi/dbs/elki/distance/distancefunction/subspace/OnedimensionalDistanceFunction.java
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+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 de.lmu.ifi.dbs.elki.data.NumberVector;
+import de.lmu.ifi.dbs.elki.data.spatial.SpatialComparable;
+import de.lmu.ifi.dbs.elki.data.type.VectorFieldTypeInformation;
+import de.lmu.ifi.dbs.elki.data.type.VectorTypeInformation;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.AbstractSpatialNorm;
+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.IntParameter;
+
+/**
+ * Distance function that computes the distance between feature vectors as the
+ * absolute difference of their values in a specified dimension only.
+ * 
+ * @author Elke Achtert
+ */
+public class OnedimensionalDistanceFunction extends AbstractSpatialNorm implements DimensionSelectingSubspaceDistanceFunction<NumberVector> {
+  /**
+   * The dimension to be considered for distance computation.
+   */
+  private int dim;
+
+  /**
+   * Constructor.
+   * 
+   * @param dim Dimension
+   */
+  public OnedimensionalDistanceFunction(int dim) {
+    super();
+    this.dim = dim;
+  }
+
+  /**
+   * Computes the distance between two given DatabaseObjects according to this
+   * distance function.
+   * 
+   * @param v1 first DatabaseObject
+   * @param v2 second DatabaseObject
+   * @return the distance between two given DatabaseObjects according to this
+   *         distance function
+   */
+  @Override
+  public double distance(NumberVector v1, NumberVector v2) {
+    if(dim >= v1.getDimensionality() || dim >= v2.getDimensionality() || dim < 0) {
+      throw new IllegalArgumentException("Specified dimension to be considered " + "is larger that dimensionality of FeatureVectors:" + "\n  first argument: " + v1.toString() + "\n  second argument: " + v2.toString() + "\n  dimension: " + dim);
+    }
+
+    double delta = v1.doubleValue(dim) - v2.doubleValue(dim);
+    return delta >= 0 ? delta : -delta;
+  }
+
+  @Override
+  public double minDist(SpatialComparable mbr1, SpatialComparable mbr2) {
+    if(dim >= mbr1.getDimensionality() || dim >= mbr2.getDimensionality() || dim < 0) {
+      throw new IllegalArgumentException("Specified dimension to be considered " + "is larger that dimensionality of FeatureVectors:" + "\n  first argument: " + mbr1.toString() + "\n  second argument: " + mbr2.toString() + "\n  dimension: " + dim);
+    }
+
+    final double max1 = mbr1.getMax(dim), min2 = mbr2.getMin(dim);
+    if(max1 < min2) {
+      return min2 - max1;
+    }
+    final double min1 = mbr1.getMin(dim), max2 = mbr2.getMax(dim);
+    if(min1 > max2) {
+      return min1 - max2;
+    }
+    return 0;
+  }
+
+  @Override
+  public double norm(NumberVector obj) {
+    return Math.abs(obj.doubleValue(dim));
+  }
+
+  /**
+   * Returns the selected dimension.
+   * 
+   * @return the selected dimension
+   */
+  public int getSelectedDimension() {
+    return dim;
+  }
+
+  @Override
+  @Deprecated
+  public long[] getSelectedDimensions() {
+    long[] bs = BitsUtil.zero(dim);
+    BitsUtil.setI(bs, dim);
+    return bs;
+  }
+
+  @Override
+  @Deprecated
+  public void setSelectedDimensions(long[] dimensions) {
+    dim = BitsUtil.nextSetBit(dimensions, 0);
+    if(dim == -1) {
+      throw new IllegalStateException("No dimension was set.");
+    }
+    if(BitsUtil.nextSetBit(dimensions, dim + 1) > 0) {
+      throw new IllegalStateException("More than one dimension was set.");
+    }
+  }
+
+  @Override
+  public VectorTypeInformation<? super NumberVector> getInputTypeRestriction() {
+    return VectorFieldTypeInformation.typeRequest(NumberVector.class, dim, Integer.MAX_VALUE);
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if(obj == null) {
+      return false;
+    }
+    if(!this.getClass().equals(obj.getClass())) {
+      return false;
+    }
+    return this.dim == ((OnedimensionalDistanceFunction) obj).dim;
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    /**
+     * Parameter for dimensionality.
+     */
+    public static final OptionID DIM_ID = new OptionID("dim", "an integer between 1 and the dimensionality of the " + "feature space 1 specifying the dimension to be considered " + "for distance computation.");
+
+    /**
+     * Selected dimension.
+     */
+    protected int dim = 0;
+
+    @Override
+    protected void makeOptions(Parameterization config) {
+      super.makeOptions(config);
+      final IntParameter dimP = new IntParameter(DIM_ID)//
+      .addConstraint(CommonConstraints.GREATER_EQUAL_ZERO_INT);
+      if(config.grab(dimP)) {
+        dim = dimP.getValue();
+      }
+    }
+
+    @Override
+    protected OnedimensionalDistanceFunction makeInstance() {
+      return new OnedimensionalDistanceFunction(dim);
+    }
+  }
+}