Dear all,

this is a total beginner question, sorry for this one, but I am stuck. Let me explain you what I plan to do:

I have preprossed one run of one subject. My aim is to extract or calculate the power law exponent of this run. How do I plan to do this? Via the following steps:

1. Take the run’s preprossed file (in my case "pb05.Subject_1.r01.scale+tlrc").
2. Calculate the fast fourier transform (FFT) to transform the time-domain of the run into its frequency-domain.
3. Take the FFT to then calculate the power-spectrum (frequency-domain) and finally the PLE.

This is my code for the FFT (step 2):

# Fast Fourier Transform (FFT)
directory=/users/philipp/desktop/fmri/dataset/subjects
for subject in subj1_exp1
do
mkdir $directory/$subject/FFT_PLE
for fMRIruns (pb05.Subject_1.r01.scale+tlrc)
do
cd $directory/$subject/preprocessing
echo "Processing $subject ..."
3dPeriodogram -prefix $directory/$subject/FFT_PLE/FFT.$fMRIruns $fMRIruns \
-nfft 1180
done
done

Now I have two questions: how is it possible via AFNI to transform the output file (FFT.pb05.Subject_1.r01.scale+tlrc), i.e., the four transformed file, into a .1D file so that I can nicely inspect the frequency-domain via AFNI (e.g., via the 1dplot option)? Of course, I can open the file just mentioned via the AFNI GUI and then display the file via a click on the GRAPH button, but this is a very silly way to do it, isn't it?

My second question would be: would you recommend to use 3dfim+ to calculate the PLE, or is there a better option with AFNI today? I read that 3dfim+ is really outdated and no longer supported.

Many thanks in advance,

Philipp