AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

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felix
December 12, 2015 11:23PM
hello afni users:

I have a functional dataset that has been projected to the surface and I would like to obtain a DFT to analyze the frequency composition. I came across the 3dDFT function and am trying to appreciate its behavior. Take for example:

3dDFT func.niml.dset

3dDFT -inverse -prefix inverse 3dDT.niml.dset

I am curious why the inverse does not approximate the initial input? Am I missing a step? In order to visually inspect this I open both datasets in SUMA and view the graph of one node. When I have done this type of analysis before (in R), the inverse FFT/nfft = the signal used in the input to the initial FFT.

Thanks,
Felix



Edited 1 time(s). Last edit at 12/14/2015 09:09AM by felix.
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Subject Author Posted

3dDFT question

felix December 12, 2015 11:23PM

Re: 3dDFT question

Emperor Zhark December 14, 2015 01:03PM

Re: 3dDFT question

felix December 14, 2015 02:01PM

Re: 3dDFT question

felix December 14, 2015 02:14PM