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Soroush
Posts:
1
Registered:
5/3/13


Problem in Idealfilter
Posted:
May 3, 2013 4:19 AM


Hi, I have a array of 200 which is a timecourse of a fMRI signal. I would like to filter it in the freq range of [.008 .1], which reveals the restingstate brain. I used the code below:
a=sim2.ts(1:200,1); %it is the original signal. Fsampling=0.33 Hz (TR=3s) count1=timeseries(a); interval=[0 0.1]; idealfilter_countn = idealfilter(count1,interval,'pass'); s3_f=idealfilter_countn.data;
But, when I plot the frequency spectrum of 's3_f', the frequencies above 0.035 has been eliminated (instead of frequency components above 0.1.



