01 /*
02 * $Id: IFFTSample.java,v 1.15 2008/02/02 03:29:45 koga Exp $
03 *
04 * Copyright (C) 2004 Koga Laboratory. All rights reserved.
05 *
06 */
07 package matxbook.chap20;
08
09 import org.mklab.nfc.matrix.DoubleComplexMatrix;
10 import org.mklab.nfc.matrix.DoubleMatrix;
11 import org.mklab.nfc.scalar.DoubleNumber;
12 import org.mklab.nfc.scalar.DoubleNumberUtil;
13
14
15 /**
16 * @author koga
17 * @version $Revision: 1.15 $, 2004/05/07
18 */
19 public class IFFTSample {
20
21 /**
22 * メインメソッド
23 *
24 * @param args コマンドライン引数
25 */
26 @SuppressWarnings("nls")
27 public static void main(String[] args) {
28 DoubleMatrix x = new DoubleMatrix(new double[] {5, 4, 8, -8, 2, 0, 0, 0}).transpose();
29 DoubleComplexMatrix xx = x.fft();
30 DoubleComplexMatrix x2 = (DoubleComplexMatrix)xx.ifft();
31 DoubleComplexMatrix x3 = (DoubleComplexMatrix)x2.roundToZeroElementWise(DoubleNumberUtil.EPS * ((DoubleNumber)x2.frobNorm()).doubleValue());
32 x3.print("ifft(fft(x))");
33 }
34 }
|