RAM use of freqstatistics

[Michael Wibral]

Dear Listusers,

I have recently started to use freqstatistics with the cfg.correctm = 'cluster' option again and I am a bit puzzled by the amount of RAM it uses - but maybe that's normal. I just want to make sure I am not overlooking some stupid mistake.

Here is the code (it uses ~20GB per 1000 randomization draws, never got it to run through 5000+ iterations):

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
PathName='/data/home1/wibral/Projects/HysteresisMEG/';
FileType='.mat';
AnalysisStr='TF_MTM_win125ms_fsm16p0Hz_Rel_';
PreprocStr='_0_cond_Preproc4LCMV_denoised_fmin0.5Hz_fmax200Hz_';

% contains the subject and date part of filename
Design={
'AEF29_HysteresisMEG_20080428';
'AKN13_HysteresisMEG_20080901';
'AZN28_HysteresisMEG_20080811';
'BAP07_HysteresisMEG_20090204';
'BRA29_HysteresisMEG_20080829';
'CHN03_HysteresisMEG_20080818';
'EKD25_HysteresisMEG_20080815';
'HZA25_HysteresisMEG_20080725';
'IWA05_HysteresisMEG_20080606';
'MBA11_HysteresisMEG_20080728';
'MTA07_HysteresisMEG_20090128';
'RRA18_HysteresisMEG_20080825';
'SKA29_HysteresisMEG_20090211';
'TSS07_HysteresisMEG_20080822';
};

for i=1:length(Design)
    fullname1=strcat(PathName,AnalysisStr,Design{i},PreprocStr, condNr1,FileType);
    load(fullname1); % a variable named TFdata or TFdataRel exists after this step
    data1{i}=TFdataRel; %
    clear TFdata; clear TFdataRel;

    fullname2=strcat(PathName,AnalysisStr,Design{i},PreprocStr, condNr2,FileType);
    load(fullname2); %a variable named TFdata or TFdataRel exists after this step
    data2{i}=TFdataRel; %
    clear TFdata; clear TFdataRel;
end;

cfg=[];
cfg.keepindividual='yes';
TFGA1 = freqgrandaverage(cfg,data1{:});
TFGA1.grad=data1{1}.grad; %get some gradiometer information for plotting
TFGA2 = freqgrandaverage(cfg,data2{:});
TFGA2.grad=data2{1}.grad; %get some gradiometer information for plotting

% do freqstatistics
cfg4stat=[];
cfg4stat.clusteralpha     = 0.05; % control admission to a cluster
cfg4stat.alpha            = 0.05; % control the false alarm rate of the permutation test
cfg4stat.avgovertime      = 'no';
cfg4stat.avgoverfreq      = 'no';
cfg4stat.avgoverchan      = 'no';
cfg4stat.statistic = 'depsamplesT'; % test statistic to evaluate the effect at the sample level
cfg4stat.numrandomization = (2^12); %
cfg4stat.correctm = 'cluster';
cfg4stat.method  = 'montecarlo';
cfg4stat.dimord = 'chan_freq_time';
cfg4stat.dim = 'chan_freq_time';
nSubjects = length(Design);
a = [1:nSubjects];
b = ones(1,nSubjects);
cfg4stat.design = [a a; b (2*b)];
cfg4stat.uvar = 1; % "subject" is unit of observation
cfg4stat.ivar = 2; % row of the design matrix that contains the independent variable

FreqStatResult = freqstatistics(cfg4stat,TFGA1,TFGA2)


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