11 May 2025 07:56:48 PM

FFT_SERIAL
  C++ version

  Demonstrate an implementation of the Fast Fourier Transform
  of a complex data vector.

  Accuracy check:

    FFT ( FFT ( X(1:N) ) ) == N * X(1:N)

             N      NITS    Error         Time          Time/Call     MFLOPS

             2     10000   7.85908e-17      0.000978      4.89e-08       204.499
             4     10000   1.20984e-16      0.002414     1.207e-07         331.4
             8     10000    6.8208e-17      0.004413    2.2065e-07       543.848
            16     10000   1.43867e-16      0.010391    5.1955e-07       615.918
            32      1000   1.33121e-16      0.002128     1.064e-06        751.88
            64      1000   1.77654e-16      0.004842     2.421e-06       793.061
           128      1000   1.92904e-16      0.010242     5.121e-06       874.829
           256      1000   2.09232e-16      0.025513   1.27565e-05       802.728
           512       100   1.92749e-16       0.00579     2.895e-05       795.855
          1024       100   2.31209e-16      0.011996     5.998e-05       853.618
          2048       100   2.44501e-16      0.026582    0.00013291       847.491
          4096       100   2.47659e-16      0.060153   0.000300765       817.116
          8192        10   2.57125e-16      0.012534     0.0006267       849.657
         16384        10    2.7363e-16      0.028103    0.00140515       816.198
         32768        10   2.92413e-16      0.057521    0.00287605       854.505
         65536        10   2.83355e-16      0.130735    0.00653675       802.062
        131072         1   3.14231e-16      0.026361     0.0131805       845.273
        262144         1     3.216e-16      0.057938      0.028969       814.421
        524288         1   3.28266e-16      0.123626      0.061813       805.775
       1048576         1   3.28448e-16      0.263904      0.131952       794.665

FFT_SERIAL:
  Normal end of execution.

11 May 2025 07:56:50 PM