Import Upstream version 0.7.0

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diff --git a/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/adapter/LnSimilarityAdapter.java b/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/adapter/LnSimilarityAdapter.java
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+++ b/elki/src/main/java/de/lmu/ifi/dbs/elki/distance/distancefunction/adapter/LnSimilarityAdapter.java
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+package de.lmu.ifi.dbs.elki.distance.distancefunction.adapter;
+
+/*
+ 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.database.query.distance.DistanceQuery;
+import de.lmu.ifi.dbs.elki.database.query.similarity.SimilarityQuery;
+import de.lmu.ifi.dbs.elki.database.relation.Relation;
+import de.lmu.ifi.dbs.elki.distance.distancefunction.DistanceFunction;
+import de.lmu.ifi.dbs.elki.distance.similarityfunction.NormalizedSimilarityFunction;
+
+/**
+ * Adapter from a normalized similarity function to a distance function using
+ * <code>-log(sim)</code>.
+ * 
+ * @author Erich Schubert
+ * 
+ * @apiviz.has Instance
+ * 
+ * @param <O> object class to process.
+ */
+public class LnSimilarityAdapter<O> extends AbstractSimilarityAdapter<O> {
+  /**
+   * Constructor.
+   * 
+   * @param similarityFunction Similarity function
+   */
+  public LnSimilarityAdapter(NormalizedSimilarityFunction<? super O> similarityFunction) {
+    super(similarityFunction);
+  }
+
+  @Override
+  public <T extends O> DistanceQuery<T> instantiate(Relation<T> database) {
+    SimilarityQuery<T> similarityQuery = similarityFunction.instantiate(database);
+    return new Instance<>(database, this, similarityQuery);
+  }
+
+  /**
+   * Distance function instance
+   * 
+   * @author Erich Schubert
+   * 
+   * @param <O> Object type
+   */
+  public static class Instance<O> extends AbstractSimilarityAdapter.Instance<O> {
+    /**
+     * Constructor.
+     * 
+     * @param database Database
+     * @param parent Parent distance
+     * @param similarityQuery similarity Query to use
+     */
+    public Instance(Relation<O> database, DistanceFunction<? super O> parent, SimilarityQuery<O> similarityQuery) {
+      super(database, parent, similarityQuery);
+    }
+
+    @Override
+    public double transform(double similarity) {
+      return -Math.log(similarity);
+    }
+  }
+
+  /**
+   * Parameterization class.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer<O> extends AbstractSimilarityAdapter.Parameterizer<O, NormalizedSimilarityFunction<? super O>> {
+    @Override
+    protected LnSimilarityAdapter<O> makeInstance() {
+      return new LnSimilarityAdapter<>(similarityFunction);
+    }
+
+    @Override
+    protected Class<? extends NormalizedSimilarityFunction<? super O>> getSimilarityRestriction() {
+      return NORMALIZED_SIMILARITY;
+    }
+  }
+}
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