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diff --git a/src/de/lmu/ifi/dbs/elki/math/statistics/kernelfunctions/TriangularKernelDensityFunction.java b/src/de/lmu/ifi/dbs/elki/math/statistics/kernelfunctions/TriangularKernelDensityFunction.java
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+++ b/src/de/lmu/ifi/dbs/elki/math/statistics/kernelfunctions/TriangularKernelDensityFunction.java
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+package de.lmu.ifi.dbs.elki.math.statistics.kernelfunctions;
+
+/*
+ This file is part of ELKI:
+ Environment for Developing KDD-Applications Supported by Index-Structures
+
+ Copyright (C) 2013
+ 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.utilities.optionhandling.AbstractParameterizer;
+
+/**
+ * Triangular kernel density estimator.
+ * 
+ * @author Erich Schubert
+ */
+public final class TriangularKernelDensityFunction implements KernelDensityFunction {
+  /**
+   * Static instance.
+   */
+  public static final TriangularKernelDensityFunction KERNEL = new TriangularKernelDensityFunction();
+
+  /**
+   * Canonical bandwidth.
+   *
+   * Computed as (R / STDDEV^4)^(1/5)
+   */
+  public static final double CANONICAL_BANDWIDTH = Math.pow(24., .2);
+
+  /**
+   * Standard deviation.
+   */
+  private static final double STDDEV = 1. / Math.sqrt(6.);
+
+  /**
+   * R constant.
+   */
+  private static final double R = 2. / 3.;
+
+  /**
+   * Private, empty constructor. Use the static instance!
+   */
+  private TriangularKernelDensityFunction() {
+    // Nothing to do.
+  }
+
+  @Override
+  public double density(double delta) {
+    return (delta < 1.) ? 1. - delta : 0.;
+  }
+
+  @Override
+  public double canonicalBandwidth() {
+    return CANONICAL_BANDWIDTH;
+  }
+
+  @Override
+  public double standardDeviation() {
+    return STDDEV;
+  }
+
+  @Override
+  public double getR() {
+    return R;
+  }
+
+  /**
+   * Parameterization stub.
+   * 
+   * @author Erich Schubert
+   * 
+   * @apiviz.exclude
+   */
+  public static class Parameterizer extends AbstractParameterizer {
+    @Override
+    protected TriangularKernelDensityFunction makeInstance() {
+      return KERNEL;
+    }
+  }
+}