[Eeglablist] interpolate bad channels - spherical interpolation

[Downey, Ryan J]

I briefly looked at the code previously (can't remember why). From what I recall, it does a linear mixture of the good channels. It's not a simple average of all channels. I would assume it is more heavily weighted to the surrounding channels but it doesn't simply look for the nearest neighbors. It uses the electrode locations to figure out how to weight the good channels to recreate the bad channels based on a spherical spline. 

The key line in eeg_interp.m is:

[tmp1 tmp2 tmp3 badchansdata] = spheric_spline( xelec, yelec, zelec, xbad, ybad, zbad, EEG.data(datachans,:));


Ryan J. Downey
Postdoctoral Associate
Human Neuromechanics Laboratory
Biomedical Engineering Dept.
University of Florida




-----Original Message-----
From: eeglablist <eeglablist-bounces at sccn.ucsd.edu> On Behalf Of Elena Geangu
Sent: Friday, July 12, 2019 7:25 AM
To: eeglablist at sccn.ucsd.edu
Subject: [Eeglablist] interpolate bad channels - spherical interpolation

Hello,
I would like to use the eeglab tool for interpolating channels (spherical
method) for replacing bad channels. I was wondering whether it interpolates a particular channel based on the average of all other channels or based on the surrounding channels?
Thanks for help.
Best wishes
elena

--
Elena Geangu, PhD

*Assistant Professor*

Psychology Department (room: B003)
University of York
Heslington, York, YO10 5DD, UK

Email: elena.geangu at york.ac.uk
Phone: 01904322865
Lab webpage  <https://urldefense.proofpoint.com/v2/url?u=https-3A__emodevlab.com&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=Xqv3i1MFyNQV9dhuL1e9BtqA0SbF1UWmfPtBzxDT0xY&m=jOfxybJ0rgKbveqiUoAlzDvtD2i6AmXmv2swM-xPs64&s=uExsxXA1cqgpOzZuForJHBhgUnV4SQLg9btAybjtaZ4&e= > _______________________________________________
Eeglablist page: https://urldefense.proofpoint.com/v2/url?u=http-3A__sccn.ucsd.edu_eeglab_eeglabmail.html&d=DwICAg&c=sJ6xIWYx-zLMB3EPkvcnVg&r=Xqv3i1MFyNQV9dhuL1e9BtqA0SbF1UWmfPtBzxDT0xY&m=jOfxybJ0rgKbveqiUoAlzDvtD2i6AmXmv2swM-xPs64&s=OCpTw1ZbfN0ybBzc-EYhYcOjl9CapT_d8PiFRozZJp4&e=
To unsubscribe, send an empty email to eeglablist-unsubscribe at sccn.ucsd.edu
For digest mode, send an email with the subject "set digest mime" to eeglablist-request at sccn.ucsd.edu