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diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/CosineDistanceFunction.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/CosineDistanceFunction.java
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+package de.lmu.ifi.dbs.elki.distance.distancefunction;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2015
+ 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.VectorUtil;
+import de.lmu.ifi.dbs.elki.data.spatial.SpatialComparable;
+import de.lmu.ifi.dbs.elki.data.type.SimpleTypeInformation;
+import de.lmu.ifi.dbs.elki.data.type.TypeUtil;
+import de.lmu.ifi.dbs.elki.utilities.Alias;
+import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;
+
+/**
+ * Cosine distance function for feature vectors.
+ * 
+ * The cosine distance is computed from the cosine similarity by
+ * <code>1-(cosine similarity)</code>.
+ * 
+ * @author Arthur Zimek
+ */
+@Alias({ "cosine" })
+public class CosineDistanceFunction extends AbstractSpatialDistanceFunction {
+  /**
+   * Static instance
+   */
+  public static final CosineDistanceFunction STATIC = new CosineDistanceFunction();
+
+  /**
+   * Constructor - use {@link #STATIC} instead.
+   * 
+   * @deprecated Use static instance
+   */
+  @Deprecated
+  public CosineDistanceFunction() {
+    super();
+  }
+
+  /**
+   * Computes the cosine distance for two given feature vectors.
+   * 
+   * The cosine distance is computed from the cosine similarity by
+   * <code>1-(cosine similarity)</code>.
+   * 
+   * @param v1 first feature vector
+   * @param v2 second feature vector
+   * @return the cosine distance for two given feature vectors v1 and v2
+   */
+  @Override
+  public double distance(NumberVector v1, NumberVector v2) {
+    double d = 1 - VectorUtil.cosAngle(v1, v2);
+    if (d < 0) {
+      d = 0;
+    }
+    return d;
+  }
+
+  @Override
+  public double minDist(SpatialComparable mbr1, SpatialComparable mbr2) {
+    double d = 1 - VectorUtil.minCosAngle(mbr1, mbr2);
+    if (d < 0) {
+      d = 0;
+    }
+    return d;
+  }
+
+  @Override
+  public String toString() {
+    return "CosineDistance";
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    if (obj == null) {
+      return false;
+    }
+    if (obj == this) {
+      return true;
+    }
+    return this.getClass().equals(obj.getClass());
+  }
+
+  @Override
+  public SimpleTypeInformation<? super NumberVector> getInputTypeRestriction() {
+    return TypeUtil.NUMBER_VECTOR_VARIABLE_LENGTH;
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    @Override
+    protected CosineDistanceFunction makeInstance() {
+      return CosineDistanceFunction.STATIC;
+    }
+  }
+}