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Bug 782 - Bug in ft_connectivityanalysis
| Status | CLOSED WORKSFORME |
| Reported | 2011-06-28 17:34:00 +0200 |
| Modified | 2011-07-13 14:46:39 +0200 |
| Product: | FieldTrip |
| Component: | core |
| Version: | unspecified |
| Hardware: | PC |
| Operating System: | Windows |
| Importance: | P1 normal |
| Assigned to: | Jan-Mathijs Schoffelen |
| URL: | |
| Tags: | |
| Depends on: | |
| Blocks: | |
| See also: |
Vladimir Litvak - 2011-06-28 17:34:20 +0200
I tried connectivity with granger on a dataset with two channels. I get the following error: stat = ft_connectivityanalysis(cfg, freq); computing multivariate non-parametric spectral factorization on 2 channels averaging crsspctrm over rpt averaging transfer over rpt removing dimension rpt from crsspctrm removing dimension rpt from transfer ??? Error using ==> reshape To RESHAPE the number of elements must not change. Error in ==> ft_connectivity_granger at 30 zc = reshape(Z(kk,jj,jj,:) - Z(kk,ii,jj,:).^2./Z(kk,ii,ii,:),[1 1 1 1 siz(5)]); Error in ==> ft_connectivityanalysis at 596 [datout, varout, nrpt] = ft_connectivity_granger(data.transfer, data.noisecov, data.crsspctrm, fs, hasjack, powindx); K>> size(Z) ans = 1 64 2 2 Investigating I found that Z comes from data.noisecov and the leading singleton dimension is added around line 407 of ft_connectivityanalysis which might not be the right thing to do for this field.
Jan-Mathijs Schoffelen - 2011-06-28 20:03:43 +0200
It seems you have repetitions in the input data?
Jan-Mathijs Schoffelen - 2011-06-28 20:06:25 +0200
could you upload a freq-structure (with not too many frequency bins) as attachment to this bug? Thanks
Jan-Mathijs Schoffelen - 2011-06-28 20:10:28 +0200
by the way, it typically makes more sense to compute a non-parametric spectral factorization on averaged data, rather than on single trials.
Vladimir Litvak - 2011-06-29 15:28:48 +0200
Created attachment 82 example data and cfg
Jan-Mathijs Schoffelen - 2011-06-29 15:51:40 +0200
>> cd ../../Desktop/ >> load granger_bug >> freq freq = label: {2x1 cell} dimord: 'rpt_chan_freq' freq: [1x101 double] powspctrm: [64x2x101 double] labelcmb: {'S2' 'S1'} crsspctrm: [64x1x101 double] cumsumcnt: [64x1 double] cumtapcnt: [64x1 double] >> cfg cfg = method: 'granger' jackknife: 'yes' bandwidth: 2.5000 >> g=ft_connectivityanalysis(cfg, freq) computing multivariate non-parametric spectral factorization on 2 channels computing jackknife crsspctrm computing jackknife transfer g = label: {2x1 cell} dimord: 'chan_chan_freq' grangerspctrm: [2x2x101 double] grangerspctrmsem: [2x2x101 double] freq: [1x101 double] cfg: [1x1 struct] I ran the code locally, and it seems my local copy is in sync with the repository. The values in the sem look strange to me, though, but it doesn't crash