AW: [Insight-users] Question about vnl_fft_1d

[Jiang]

Hi Luis,
I modified my code as the update example. Now it works fine. Thank you
very much for your consideration.
Now the curve's Fourier Transform can be get. The coefficient in all
frequency bands is calculated. The spectrum analysis is needed for
quantifying the smoothness of the curve. Could you introduce me such
classic method to perform the analyzing?


Thank you very much!

Best regards
Chunyan Jiang


-----Ursprüngliche Nachricht-----
Von: insight-users-bounces at itk.org
[mailto:insight-users-bounces at itk.org] Im Auftrag von Luis Ibanez
Gesendet: Mittwoch, 7. Juli 2004 03:03
An: Jiang
Cc: ITK
Betreff: Re: [Insight-users] Question about vnl_fft_1d


Hi Jiang,

Thanks for pointing this out.

This seems to be a bug in the example.

The fftCalculator should be constructed with
"spectrumSize" instead of "numberOfPoints".

spectrumSize is the smalles power of two that
is larger than the number of points.

Please find attached the fixed version,
or simply update your CVS checkou where
the fix has been made.


Please let us know if you find any further
problems,


    Thanks


      Luis