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<p class="MsoNormal">Hello Fieldtrip experts,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I am using fieldtrip to do LCMV source analysis. I have a dataset of baseline and 3 exposures to nitrous oxide of which I have 1 minute of EEG recording each. For the analysis I split the 60 second recording into 2 second trials using redefine
trial. This creates a struct with the 30 trials and 30 time axis each trial having its own time axis 0:2 2:4 etc. When calling the timelock analysis for the covariance matrix (with keep trials on) on this dataset I get a struct:<o:p></o:p></p>
<p class="MsoNormal"> time: [1×15360 double]<o:p></o:p></p>
<p class="MsoNormal"> label: {32×1 cell}<o:p></o:p></p>
<p class="MsoNormal"> trial: [55×32×15360 double]<o:p></o:p></p>
<p class="MsoNormal"> dimord: 'rpt_chan_time'<o:p></o:p></p>
<p class="MsoNormal"> cov: [55×32×32 double]<o:p></o:p></p>
<p class="MsoNormal"> cfg: [1×1 struct]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This struct has 1 time axis from 0:60 seconds (fsample=256), with all the trials having their data on the correct time padded with NaNs before and after.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Is this structure useful (keeping the original time axis 0:60) for the source analysis, or is it better to redefine the time axis for all trials to be 0:2? Is there a Fieldtrip function/setting to achieve this? The downside I currently
experience is that the data struct is getting very big, causing an out of memory error.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you so much for helping me.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Xavier Vrijdag<o:p></o:p></p>
<p class="MsoNormal">PhD student <o:p></o:p></p>
<p class="MsoNormal">University of Auckland<o:p></o:p></p>
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