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<p class="MsoNormal">Dear FT community , <o:p></o:p></p>
<p class="MsoNormal">I tried to use ft_headmovement to adjust my grad structure in order to account for head movement before source reconstruction.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I run into the following problem:<o:p></o:p></p>
<p class="MsoNormal"><span style="color:#00B050"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#00B050">% code<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">cfg = [];<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">cfg.dataset = filenames{1};<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">cfg.trl = trl_used;<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#002060">[grad_adj] = ft_headmovement(cfg);<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%">>> output<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%">processing channel { 'HLC0011' 'HLC0012' 'HLC0013' 'HLC0021' 'HLC0022' 'HLC0023' 'HLC0031' 'HLC0032' 'HLC0033' }<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%">reading and preprocessing<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%">reading and preprocessing trial 687 from 687<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#595959;mso-style-textfill-fill-color:#595959;mso-style-textfill-fill-alpha:100.0%">the call to "ft_preprocessing" took 58 seconds and required the additional allocation of an estimated 14 MB<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span style="color:red">>> error<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red">Error using kmeans (line 262)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red">X must have more rows than the number of clusters.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:red">Error in ft_headmovement (line 125)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red">[bin, cluster] = kmeans(dat', cfg.numclusters);<o:p></o:p></span></p>
<p class="MsoNormal">----------------------------------------------------------------------<o:p></o:p></p>
<p class="MsoNormal"><o:p></o:p></p>
<p class="MsoNormal">The problem is, that the dat passed to kmeans clustering is empty.
<o:p></o:p></p>
<p class="MsoNormal">It seems that only headpositions that are at least 100 times present in the downsampled data are actually considered for clustering.
<o:p></o:p></p>
<p class="MsoNormal">I don’t understand the reason for that, especially since the data is not rounded and scaled in ‘mm’ (there are a lot of tiny changes between the sampling points)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks for any suggestions!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">All the best,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Sebastian<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This is in line 92 of the function<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="DE">dat = zeros(length(data.label), 0);<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE">wdat = zeros(1, 0);<o:p></o:p></span></p>
<p class="MsoNormal">for k = 1:length(data.trial)<o:p></o:p></p>
<p class="MsoNormal"> tmpdat = data.trial{k};<o:p></o:p></p>
<p class="MsoNormal"> utmpdat = unique(tmpdat','rows')';<o:p></o:p></p>
<p class="MsoNormal"> <span lang="DE">dat = [dat utmpdat];<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="DE"> wtmpdat = zeros(1,size(utmpdat,2));<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="DE"> </span>for m = 1:size(utmpdat,2)<o:p></o:p></p>
<p class="MsoNormal"> wtmpdat(1,m) = sum(sum(tmpdat-utmpdat(:,m)*ones(1,size(tmpdat,2))==0,1)==9);<o:p></o:p></p>
<p class="MsoNormal"> end<o:p></o:p></p>
<p class="MsoNormal"> wdat = [wdat wtmpdat];<o:p></o:p></p>
<p class="MsoNormal">end<o:p></o:p></p>
<p class="MsoNormal"><span style="color:red">dat(:, wdat<100) = [];<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:red">wdat(wdat<100) = [];<o:p></o:p></span></p>
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