Number of bins in 3dLombScargle

AFNI Message Board
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Dear AFNI people (and dear Paul),

I have a question concerning the Lomb-Scargle Periodogram and its AFNI implementation, namely 3dLombScargle.

The number of bins in the frequency-domain that are created by 3dLombScargle are defined by 1/T, where T is the duration or number of sampling points of the time-series (in TRs, I assume).

Is there a way to change the number of bins, like in a standard Periodogram via adjusting the nfft value? Or is that generally not possible due to the different computation of the Lomb-Scargle Periodogram, so that the number of bins is always determined by the length of the time-series?
In case it would be principally possible, is there any chance that this feature will be implemented in 3dLombScargle in the future?

One of the reasons why I am asking this is because it would be nicer to have the exact same amount of bins when comparing runs of different lengths.

Thanks,
Philipp

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Philipp-

This implementation doesn’t have a way to adjust the binning. I guess “mean padding” the time series would be one way to go, but I have not tried that.

–pt

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Thanks for clarifying this, Paul.