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

History of AFNI updates  

|
October 25, 2008 12:56PM
Hi,

I performed a power spectrum analysis on an epi scan with 84 repititions using the afni power spectrum plug-in. The attachments "time_series.pdf" and "spectrum.pdf" shows the intensity versus time and the power spectrum, respectively, of one voxel. That power spectrum cannot be real. The real power spectrum of the time series should have a very sharp maximum at f = 0, which I verified using Matlab.

Any idea what might be the reason? Has anyone encountered similar problem before?

Thanks,
Xiaopeng
Subject Author Posted

problem using power spectrum plugin

xiaopeng October 25, 2008 12:56PM

Re: problem using power spectrum plugin

Xiaopeng October 26, 2008 12:04AM