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diff --git a/elki/src/test/java/de/lmu/ifi/dbs/elki/distance/similarityfunction/kernel/PolynomialKernelFunctionTest.java b/elki/src/test/java/de/lmu/ifi/dbs/elki/distance/similarityfunction/kernel/PolynomialKernelFunctionTest.java
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+++ b/elki/src/test/java/de/lmu/ifi/dbs/elki/distance/similarityfunction/kernel/PolynomialKernelFunctionTest.java
@@ -0,0 +1,71 @@
+package de.lmu.ifi.dbs.elki.distance.similarityfunction.kernel;
+
+/*
+ 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 static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+import de.lmu.ifi.dbs.elki.JUnit4Test;
+import de.lmu.ifi.dbs.elki.data.DoubleVector;
+
+/**
+ * Unit test for Kernel implementation.
+ *
+ * @author Erich Schubert
+ * @since 0.7.1
+ */
+public class PolynomialKernelFunctionTest implements JUnit4Test {
+  @Test
+  public void testToyExamplesPoly2() {
+    DoubleVector v1 = new DoubleVector(new double[] { 1, 0, 0 });
+    DoubleVector v2 = new DoubleVector(new double[] { 0, 1, 0 });
+    DoubleVector v3 = new DoubleVector(new double[] { 1, 1, 1 });
+    DoubleVector v4 = new DoubleVector(new double[] { .1, .2, .3 });
+
+    PolynomialKernelFunction kernel = new PolynomialKernelFunction(2);
+    assertEquals("Linear kernel not correct.", 0., kernel.similarity(v1, v2), 0.);
+    assertEquals("Linear kernel not correct.", 1., kernel.similarity(v1, v3), 0.);
+    assertEquals("Linear kernel not correct.", .01, kernel.similarity(v1, v4), 1e-13);
+    assertEquals("Linear kernel not correct.", 1., kernel.similarity(v2, v3), 0.);
+    assertEquals("Linear kernel not correct.", .04, kernel.similarity(v2, v4), 1e-13);
+    assertEquals("Linear kernel not correct.", .36, kernel.similarity(v3, v4), 1e-13);
+  }
+
+  @Test
+  public void testToyExamplesPoly3() {
+    DoubleVector v1 = new DoubleVector(new double[] { 1, 0, 0 });
+    DoubleVector v2 = new DoubleVector(new double[] { 0, 1, 0 });
+    DoubleVector v3 = new DoubleVector(new double[] { 1, 1, 1 });
+    DoubleVector v4 = new DoubleVector(new double[] { .1, .2, .3 });
+
+    PolynomialKernelFunction kernel = new PolynomialKernelFunction(3);
+    assertEquals("Linear kernel not correct.", 0., kernel.similarity(v1, v2), 0.);
+    assertEquals("Linear kernel not correct.", 1., kernel.similarity(v1, v3), 0.);
+    assertEquals("Linear kernel not correct.", .001, kernel.similarity(v1, v4), 1e-13);
+    assertEquals("Linear kernel not correct.", 1., kernel.similarity(v2, v3), 0.);
+    assertEquals("Linear kernel not correct.", .008, kernel.similarity(v2, v4), 1e-13);
+    assertEquals("Linear kernel not correct.", .216, kernel.similarity(v3, v4), 1e-13);
+  }
+}
+\ No newline at end of file