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diff --git a/src/main/java/com/jsyn/data/FloatSample.java b/src/main/java/com/jsyn/data/FloatSample.java
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+/*
+ * Copyright 2010 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.data;
+
+import com.jsyn.unitgen.FixedRateMonoReader;
+import com.jsyn.unitgen.FixedRateStereoReader;
+import com.jsyn.unitgen.VariableRateMonoReader;
+import com.jsyn.unitgen.VariableRateStereoReader;
+import com.jsyn.util.SampleLoader;
+
+/**
+ * Store multi-channel floating point audio data in an interleaved buffer. The values are stored as
+ * 32-bit floats. You can play samples using one of the readers, for example VariableRateMonoReader.
+ *
+ * @author Phil Burk (C) 2010 Mobileer Inc
+ * @see SampleLoader
+ * @see FixedRateMonoReader
+ * @see FixedRateStereoReader
+ * @see VariableRateMonoReader
+ * @see VariableRateStereoReader
+ */
+public class FloatSample extends AudioSample implements Function {
+    private float[] buffer;
+
+    public FloatSample() {
+    }
+
+    /** Constructor for mono samples. */
+    public FloatSample(int numFrames) {
+        this(numFrames, 1);
+    }
+
+    /** Constructor for mono samples with data. */
+    public FloatSample(float[] data) {
+        this(data.length, 1);
+        write(data);
+    }
+
+    /** Constructor for multi-channel samples with data. */
+    public FloatSample(float[] data, int channelsPerFrame) {
+        this(data.length / channelsPerFrame, channelsPerFrame);
+        write(data);
+    }
+
+    /**
+     * Create a silent sample with enough memory to hold the audio data. The number of sample
+     * numbers in the array will be numFrames*channelsPerFrame.
+     *
+     * @param numFrames number of sample groups. A stereo frame contains 2 samples.
+     * @param channelsPerFrame 1 for mono, 2 for stereo
+     */
+    public FloatSample(int numFrames, int channelsPerFrame) {
+        allocate(numFrames, channelsPerFrame);
+    }
+
+    /**
+     * Allocate memory to hold the audio data. The number of sample numbers in the array will be
+     * numFrames*channelsPerFrame.
+     *
+     * @param numFrames number of sample groups. A stereo frame contains 2 samples.
+     * @param channelsPerFrame 1 for mono, 2 for stereo
+     */
+    @Override
+    public void allocate(int numFrames, int channelsPerFrame) {
+        buffer = new float[numFrames * channelsPerFrame];
+        this.numFrames = numFrames;
+        this.channelsPerFrame = channelsPerFrame;
+    }
+
+    /**
+     * Note that in a stereo sample, a frame has two values.
+     *
+     * @param startFrame index of frame in the sample
+     * @param data data to be written
+     * @param startIndex index of first value in array
+     * @param numFrames
+     */
+    public void write(int startFrame, float[] data, int startIndex, int numFrames) {
+        int numSamplesToWrite = numFrames * channelsPerFrame;
+        int firstSampleIndexToWrite = startFrame * channelsPerFrame;
+        System.arraycopy(data, startIndex, buffer, firstSampleIndexToWrite, numSamplesToWrite);
+    }
+
+    /**
+     * Note that in a stereo sample, a frame has two values.
+     *
+     * @param startFrame index of frame in the sample
+     * @param data array to receive the data from the sample
+     * @param startIndex index of first location in array to start filling
+     * @param numFrames
+     */
+    public void read(int startFrame, float[] data, int startIndex, int numFrames) {
+        int numSamplesToRead = numFrames * channelsPerFrame;
+        int firstSampleIndexToRead = startFrame * channelsPerFrame;
+        System.arraycopy(buffer, firstSampleIndexToRead, data, startIndex, numSamplesToRead);
+    }
+
+    /**
+     * Write the entire array to the sample. The sample data must have already been allocated with
+     * enough room to contain the data.
+     *
+     * @param data
+     */
+    public void write(float[] data) {
+        write(0, data, 0, data.length / getChannelsPerFrame());
+    }
+
+    public void read(float[] data) {
+        read(0, data, 0, data.length / getChannelsPerFrame());
+    }
+
+    @Override
+    public double readDouble(int index) {
+        return buffer[index];
+    }
+
+    @Override
+    public void writeDouble(int index, double value) {
+        buffer[index] = (float) value;
+    }
+
+    /**
+     * Interpolate between two adjacent samples.
+     * Note that this will only work for mono, single channel samples.
+     *
+     * @param fractionalIndex must be >=0 and < (size-1)
+     */
+    public double interpolate(double fractionalIndex) {
+        int index = (int) fractionalIndex;
+        float phase = (float) (fractionalIndex - index);
+        float source = buffer[index];
+        float target = buffer[index + 1];
+        return ((target - source) * phase) + source;
+    }
+
+    /**
+     * Note that this will only work for mono, single channel samples.
+     */
+    @Override
+    public double evaluate(double input) {
+        // Input ranges from -1 to +1
+        // Map it to range of sample with guard point.
+        double normalizedInput = (input + 1.0) * 0.5;
+        // Clip so it does not go out of range of the sample.
+        if (normalizedInput < 0.0) normalizedInput = 0.0;
+        else if (normalizedInput > 1.0) normalizedInput = 1.0;
+        double fractionalIndex = (getNumFrames() - 1.01) * normalizedInput;
+        return interpolate(fractionalIndex);
+    }
+}