19 January 2020 11:34:57 AM

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  7.859082e-17  1.140000e-03  5.700000e-08    175.438596
             4     10000  1.209837e-16  2.556000e-03  1.278000e-07    312.989045
             8     10000  6.820795e-17  4.595000e-03  2.297500e-07    522.306855
            16     10000  1.438671e-16  1.239700e-02  6.198500e-07    516.253932
            32      1000  1.331210e-16  2.340000e-03  1.170000e-06    683.760684
            64      1000  1.776545e-16  6.231000e-03  3.115500e-06    616.273471
           128      1000  1.929043e-16  1.104800e-02  5.524000e-06    811.006517
           256      1000  2.092319e-16  2.790300e-02  1.395150e-05    733.971258
           512       100  1.927488e-16  5.153000e-03  2.576500e-05    894.236367
          1024       100  2.308607e-16  1.309000e-02  6.545000e-05    782.276547
          2048       100  2.447624e-16  2.927300e-02  1.463650e-04    769.582892
          4096       100  2.479782e-16  6.133200e-02  3.066600e-04    801.408726
          8192        10  2.578088e-16  1.286300e-02  6.431500e-04    827.925056
         16384        10  2.733986e-16  2.714000e-02  1.357000e-03    845.158438
         32768        10  2.923012e-16  5.931600e-02  2.965800e-03    828.646571
         65536        10  2.829927e-16  1.297160e-01  6.485800e-03    808.362885
        131072         1  3.149670e-16  2.688600e-02  1.344300e-02    828.767388
        262144         1  3.218597e-16  5.723200e-02  2.861600e-02    824.467431
        524288         1  3.281373e-16  1.228870e-01  6.144350e-02    810.620489
       1048576         1  3.285898e-16  2.796540e-01  1.398270e-01    749.909531

FFT_SERIAL:
  Normal end of execution.

19 January 2020 11:34:58 AM