edu.mines.jtk.bench.FftBench Maven / Gradle / Ivy

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Copyright 2005, Colorado School of Mines and others.
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,
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****************************************************************************/
package edu.mines.jtk.bench;

import edu.mines.jtk.dsp.FftComplex;
import static edu.mines.jtk.util.ArrayMath.crandfloat;
import edu.mines.jtk.util.Stopwatch;

/**
 * Benchmark FFTs.
 * @author Dave Hale, Colorado School of Mines
 * @version 2005.03.24
 */
public class FftBench {
  public static void main(String[] args) {
    for (int niter=0; niter<5; ++niter) {
      for (int nfft=1; nfft<=720720;) {
        int nfftSmall = FftComplex.nfftSmall(nfft);
        int nfftFast = FftComplex.nfftFast(nfft);
        double timeSmall = time(nfftSmall);
        if (nfftFast==nfftSmall) {
          System.out.printf("nsmall=%d tsmall=%.14f\n",nfftSmall,timeSmall);
        } else {
          double timeFast = (nfftFast>nfftSmall)?time(nfftFast):timeSmall;
          System.out.printf("nsmall=%d tsmall=%.14f tfast=%.14f\n",
            nfftSmall,timeSmall,timeFast);
          if (timeSmall