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diff --git a/tests/com/jsyn/util/TestFFT.java b/tests/com/jsyn/util/TestFFT.java
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+++ b/tests/com/jsyn/util/TestFFT.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;
+
+import com.softsynth.math.FourierMath;
+
+public class TestFFT extends TestCase {
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+    }
+
+    @Override
+    protected void tearDown() throws Exception {
+        super.tearDown();
+    }
+
+    public void checkSingleSine(int size, int bin) {
+        double[] ar = new double[size];
+        double[] ai = new double[size];
+        double[] magnitudes = new double[size];
+
+        double amplitude = 1.0;
+        addSineWave(size, bin, ar, amplitude);
+
+        FourierMath.transform(1, size, ar, ai);
+        FourierMath.calculateMagnitudes(ar, ai, magnitudes);
+
+        assertTrue(magnitudes[bin - 1] < 0.001);
+        assertTrue(magnitudes[bin] > 0.5);
+        assertTrue(magnitudes[bin + 1] < 0.001);
+
+    }
+
+    private void addSineWave(int size, int bin, double[] ar, double amplitude) {
+        double phase = 0.0;
+        double phaseIncrement = 2.0 * Math.PI * bin / size;
+        for (int i = 0; i < size; i++) {
+            ar[i] += Math.sin(phase) * amplitude;
+            // System.out.println( i + " = " + ar[i] );
+            phase += phaseIncrement;
+        }
+    }
+
+    public void testSingles() {
+        checkSingleSine(32, 1);
+        checkSingleSine(32, 2);
+        checkSingleSine(64, 5);
+        checkSingleSine(256, 3);
+    }
+
+    public void checkInverseFFT(int size, int bin) {
+        double[] ar1 = new double[size];
+        double[] ai1 = new double[size];
+        double[] ar2 = new double[size];
+        double[] ai2 = new double[size];
+
+        double amplitude = 1.0;
+        addSineWave(size, bin, ar1, amplitude);
+
+        // Save a copy of the source.
+        System.arraycopy(ar1, 0, ar2, 0, size);
+        System.arraycopy(ai1, 0, ai2, 0, size);
+
+        FourierMath.transform(1, size, ar1, ai1); // FFT
+
+        FourierMath.transform(-1, size, ar1, ai1); // IFFT
+
+        for (int i = 0; i < size; i++) {
+            assertEquals(ar2[i], ar1[i], 0.00001);
+            assertEquals(ai2[i], ai1[i], 0.00001);
+        }
+    }
+
+    public void testInverse() {
+        checkInverseFFT(32, 1);
+        checkInverseFFT(32, 2);
+        checkInverseFFT(128, 17);
+        checkInverseFFT(512, 23);
+    }
+}