plv analysis

[Bernhard Spitzer]

Dear ft_list,

I am trying to perform plv analysis using Fieldtrip, on EEG data
converted from SPM to Fieldtrip using ftraw.
Frequanalysis on the imported data works fine, I obtain the powspctrm
and crsspctrm, and I can succeed
with connectivityanalyis to compute e.g., coherence without problems.
However, when I set cfg.method to 'plv', connectivityanalysis throws the
following error:

??? Conversion to cell from double is not possible.

Error in ==> avgoverdim at 17
reduceddim(avgdimnum) = 1;

Error in ==> selectdata at 445
     if avgoverrpt,  tmpdata = avgoverdim(tmpdata, 'rpt');   end

Error in ==> ft_connectivityanalysis at 256
     data   = selectdata(data, 'avgoverrpt', 'yes');

any suggestions?
best & many thanks
Bernhard



%Here the settings I use for  frequanalysis (which seems to work fine)
cfg = [];
cfg.output ='powandcsd';
cfg.taper = 'dpss';
cfg.channel = unique(S.chancomb(:));
cfg.channelcmb = S.chancomb;
cfg.method          = 'mtmconvol';
cfg.keeptrials = 'yes';
cfg.keeptapers = 'no';
cfg.foi             = (1/timewin):(1/timewin):S.freqwin(2); % Frequency axis
cfg.foi             = cfg.foi(cfg.foi>=S.freqwin(1));
numfoi              = length(cfg.foi);
cfg.t_ftimwin       = zeros(1,numfoi);
cfg.t_ftimwin(:)    = timewin; % Time resolution
cfg.tapsmofrq       = zeros(1,numfoi); % Initialize to zero
cfg.tapsmofrq(:)    = 1/timewin; % Set initial resolution to 1/timewin
(i.e. 2.5 Hz) for all frequencis
cfg.tapsmofrq(cfg.foi>10*(1/timewin))    =
0.1*cfg.foi(cfg.foi>10*(1/timewin));
cfg.tapsmofrq(cfg.foi>50)                = 5;
cfg.toi=(prestim+(timewin/2)):step:(poststim-(timewin/2)-1/data.fsample); %
Time axis
freq = ft_freqanalysis(cfg, data);

%And the part for connectivityanalysis (which works for coherence, but
not for plv)
cfg=[];
cfg.method  = 'plv';
[stat] = ft_connectivityanalysis(cfg,  freqs)

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