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diff --git a/tests/com/jsyn/util/TestPseudoRandom.java b/tests/com/jsyn/util/TestPseudoRandom.java
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+++ b/tests/com/jsyn/util/TestPseudoRandom.java
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+/*
+ * Copyright 2009 Phil Burk, Mobileer Inc
+ *
+ * Licensed 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 com.jsyn.util;
+
+import junit.framework.TestCase;
+
+public class TestPseudoRandom extends TestCase {
+    PseudoRandom pseudoRandom;
+    private int[] bins;
+    private final static int BIN_SHIFTER = 8;
+    private final static int BIN_COUNT = 1 << BIN_SHIFTER;
+    private final static int BIN_MASK = BIN_COUNT - 1;
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        pseudoRandom = new PseudoRandom();
+        bins = new int[BIN_COUNT];
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        super.tearDown();
+    }
+
+    public void testMath() {
+        long seed = 3964771111L;
+        int positiveInt = (int) (seed & 0x7FFFFFFF);
+        assertTrue("masked random positive, " + positiveInt, (positiveInt >= 0));
+        double rand = positiveInt * (1.0 / (1L << 31));
+        assertTrue("not too low, " + rand, (rand >= 0.0));
+        assertTrue("not too high, " + rand, (rand < 1.0));
+    }
+
+    public void testIntegerDistribution() {
+        int scaler = 10;
+        for (int i = 0; i < (bins.length * scaler); i++) {
+            int rand = pseudoRandom.nextRandomInteger();
+            int positiveInt = rand & 0x7FFFFFFF;
+            assertTrue("masked random " + positiveInt, (positiveInt >= 0));
+            int index = (rand >> (32 - BIN_SHIFTER)) & BIN_MASK;
+            bins[index] += 1;
+        }
+        checkDistribution(scaler);
+    }
+
+    public void test01Distribution() {
+        int scaler = 10;
+        for (int i = 0; i < (bins.length * scaler); i++) {
+            double rand = pseudoRandom.random();
+            assertTrue("not too low, #" + i + " = " + rand, (rand >= 0.0));
+            assertTrue("not too high, #" + i + " = " + rand, (rand < 1.0));
+            int index = (int) (rand * BIN_COUNT);
+            bins[index] += 1;
+        }
+        checkDistribution(scaler);
+    }
+
+    private void checkDistribution(int scaler) {
+        // Generate running average that should stay near scaler
+        double average = scaler;
+        double coefficient = 0.9;
+        for (int i = 0; i < (bins.length); i++) {
+            average = (average * coefficient) + (bins[i] * (1.0 - coefficient));
+            assertEquals("average at " + i, scaler, average, 0.2 * scaler);
+        }
+    }
+}