svn commit: r889777 - /lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java

[sr...@apache.org]

Author: srowen
Date: Fri Dec 11 19:22:16 2009
New Revision: 889777

URL: http://svn.apache.org/viewvc?rev=889777&view=rev
Log:
MAHOUT-219

Added:
    lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java

Added: lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java
URL: http://svn.apache.org/viewvc/lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java?rev=889777&view=auto
==============================================================================
--- lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java (added)
+++ lucene/mahout/trunk/matrix/src/test/java/org/apache/mahout/matrix/GenericSortingTest.java Fri Dec 11 19:22:16 2009
@@ -0,0 +1,97 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.mahout.matrix;
+
+import org.apache.mahout.matrix.function.IntComparator;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class GenericSortingTest extends Assert {
+
+	private static class SomethingToSort implements Swapper, IntComparator {
+		private final int[] data;
+
+		private SomethingToSort(int[] data) {
+			this.data = data;
+		}
+
+		@Override
+		public void swap(int a, int b) {
+			int temp = data[a];
+			data[a] = data[b];
+			data[b] = temp;
+		}
+
+		@Override
+		public int compare(int o1, int o2) {
+			if (data[o1] < data[o2]) {
+				return -1;
+			} else if (data[o1] > data[o2]) {
+				return 1;
+			} else {
+				return 0;
+			}
+		}
+	}
+
+	@Test
+	public void testQuickSort() {
+		int[] td = new int[20];
+		for (int x = 0; x < 20; x ++) {
+			td[x] = 20 - x;
+		}
+		SomethingToSort sts = new SomethingToSort(td);
+		GenericSorting.quickSort(0, 20, sts, sts);
+		for (int x = 0; x < 20; x ++) {
+			assertEquals(x+1, td[x]);
+		}
+	}
+
+	private static class SomethingToSortStable implements Swapper, IntComparator {
+		private final String[] data;
+
+		private SomethingToSortStable(String[] data) {
+			this.data = data;
+		}
+
+		@Override
+		public void swap(int a, int b) {
+			String temp = data[a];
+			data[a] = data[b];
+			data[b] = temp;
+		}
+
+		@Override
+		public int compare(int o1, int o2) {
+			return data[o1].compareTo(data[o2]);
+		}
+	}
+
+	@Test
+	public void testMergeSort() {
+		String[] sd = {"z", "a", "a", "q", "1"};
+		String[] correct = {"1", "a", "a", "q", "z"};
+
+		SomethingToSortStable sts = new SomethingToSortStable(sd);
+		GenericSorting.mergeSort(0, 5, sts, sts);
+
+		for (int x = 0; x < 5; x ++) {
+      assertSame(correct[x], sd[x]);
+		}
+	}
+}