/****************************************************************************** * Compilation: javac PlayThatTune.java * Execution: java PlayThatTune < input.txt * Dependencies: StdAudio.java StdAudio.java * * This is a data-driven program that plays pure tones from * the notes on the chromatic scale, specified on standard input * by their distance from concert A. * * % java PlayThatTune < elise.txt * * * Data files * ---------- * https://introcs.cs.princeton.edu/java/21function/elise.txt * https://introcs.cs.princeton.edu/java/21function/99luftballons.txt * https://introcs.cs.princeton.edu/java/21function/freebird.txt * https://introcs.cs.princeton.edu/java/21function/Ascale.txt * https://introcs.cs.princeton.edu/java/21function/National_Anthem.txt * https://introcs.cs.princeton.edu/java/21function/looney.txt * https://introcs.cs.princeton.edu/java/21function/StairwayToHeaven.txt * https://introcs.cs.princeton.edu/java/21function/entertainer.txt * https://introcs.cs.princeton.edu/java/21function/old-nassau.txt * https://introcs.cs.princeton.edu/java/21function/arabesque.txt * https://introcs.cs.princeton.edu/java/21function/firstcut.txt * https://introcs.cs.princeton.edu/java/21function/tomsdiner.txt * https://introcs.cs.princeton.edu/java/21function/portal.txt * ******************************************************************************/ public class PlayThatTune { public static void main(String[] args) { // repeat as long as there are more integers to read in while (!StdIn.isEmpty()) { // read in the pitch, where 0 = Concert A int pitch = StdIn.readInt(); // read in duration in seconds double duration = StdIn.readDouble(); // build sine wave with desired frequency double hz = 440 * Math.pow(2, pitch / 12.0); int n = (int) (StdAudio.SAMPLE_RATE * duration); double[] a = new double[n+1]; for (int i = 0; i <= n; i++) { a[i] = Math.sin(2 * Math.PI * i * hz / StdAudio.SAMPLE_RATE); } // play it using standard audio StdAudio.play(a); } } }