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Dear AFNI users-
We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:
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
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
| October 25, 2008 01:07AM | |
The Fourier filter works by taking the fast Fourier transform of the timeseries, then zeroing out the values outside of the specified frequency cutoff(s), then performing an inverse FFT.
It should mean that there is no loss in the passband and total attenuation in the stopband.
I think it also might mean the order of the filter is infinity.
I got this from reading the source code, by the way.
You might receive more helpful answers if you say more about your application, with particular attention to how exactly the application is affected by the specific characteristics of the filter. Of course those answers would have to come from someone else, I am just a source-code-reading robot with no actual grasp of what I'm talking about.
Also I could be wrong about the loss and attenuation.
It should mean that there is no loss in the passband and total attenuation in the stopband.
I think it also might mean the order of the filter is infinity.
I got this from reading the source code, by the way.
You might receive more helpful answers if you say more about your application, with particular attention to how exactly the application is affected by the specific characteristics of the filter. Of course those answers would have to come from someone else, I am just a source-code-reading robot with no actual grasp of what I'm talking about.
Also I could be wrong about the loss and attenuation.
| Subject | Author | Posted |
|---|---|---|
|
Donald McLaren | October 24, 2008 04:21PM |
|
David Perlman | October 25, 2008 01:07AM |
