Code get stuck with nested loop and computer crashes after

I am having an issue to run this block of code:

clear all

set(0,'DefaultFigureVisible','off');

a_data = cell(1,12560);

fft_a_data = cell(1,12560);

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%%%%%Code lines here before%%%%%

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count = 1;

for p2 = 1:a_trials

for p1 = 1:16

figHandle = figure;

topoplot(a_data(p1,:,p2),EEG.chanlocs,'style','map');

[X, Map] = frame2im(getframe(figHandle));

a_data{count} = X;

%FFT

Y = fft(a_data(p1,:,p2));

P2 = abs(Y/L);

P1 = P2(1:L/2+1);

P1(2:end-1) = 2*P1(2:end-1);

figHandle = figure;

topoplot(P1(fft_index),EEG.chanlocs,'style','map');

[X_fft, Map_fft] = frame2im(getframe(figHandle));

fft_a_data{count} = X_fft;

count = count + 1;

end

end

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%%%%%Code lines here after%%%%%

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

set(0,'DefaultFigureVisible','on');

At the beginning the computer looks like running it but after it stops and whole system crashes, how should I handle this issue? When I consider a range for p2=1:5 and p1=1:5 it is running normally but to this range p2=1:785 I can't able to perform it. The topoplot belongs to EEGLab toolbox.

Answer 1

[Image Analyst]

Why are you plotting those things anyway? Just to look at them? How about if you just opened a figure before the loops, and then looked at the pair of plots inside the inner loop? You're overwriting X, Map, X_fft, and Map_fft on each inner loop iteration anyway. Why? Were you planning on making a movie out of all of them?

clear all
% set(0,'DefaultFigureVisible','off');
a_trials = 2; % Whatever...
a_data = cell(1,12560);
fft_a_data = cell(1,12560);
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%%%%%Code lines here before%%%%%
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count = 1;
abort = false;
% Create new figure and maximize it.
figHandle = figure;
figHandle.WindowState = 'maximized';
for p2 = 1:a_trials
    for p1 = 1:16
        % Make first plot in upper half of the figure.
        h1 = subplot(2, 1, 1);
        cla;
        topoplot(a_data(p1,:,p2),EEG.chanlocs,'style','map');
        [X, Map] = frame2im(getframe(h1));
        a_data{count} = X;
        
        %FFT
        Y = fft(a_data(p1,:,p2));
        P2 = abs(Y/L);
        P1 = P2(1:L/2+1);
        P1(2:end-1) = 2*P1(2:end-1);
        
        % Make second plot in lower half of the figure.
        h2 = subplot(2, 1, 1);
        cla;
        topoplot(P1(fft_index),EEG.chanlocs,'style','map');
        [X_fft, Map_fft] = frame2im(getframe(h2));
        fft_a_data{count} = X_fft;
        count = count + 1;
        promptMessage = sprintf('Look at your plots for p1=%d and p2=%d.\nDo you want to Continue processing,\nor Quit processing?', p1, p2);
        titleBarCaption = 'Continue?';
        buttonText = questdlg(promptMessage, titleBarCaption, 'Continue', 'Quit', 'Continue');
        if contains(buttonText, 'Quit', 'IgnoreCase', true)
            abort = true;
            break; % or break or continue.
        end
    end
    if abort
        break;
    end
end
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%%%%%Code lines here after%%%%%
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% set(0,'DefaultFigureVisible','on');

[Victor Gimenez]

Hey there @Image Analyst, thank you for this "shook"!!! In fact my knowledge is very basic in MATLAB's image processing functions and techniques, this method call and attribution: figHandle = figure; I followed it through the topoplot EEGLab function but I stayed confused the difference between execute topoplot directly that I realized that I can open the figure and call figure and after topoplot, and I was unfamiliar with the WindowState attribute also, big thanks for your help again you saved me!! I am gonna study more this implementation and follow this idea on the next scripts!!

Answer 2

[Jan]

What is a_trials?

It looks like you want to run 12560 iteration. You open two figures in each iteration, so there is a total of 25120 open figures. Although they are invisible, they need a lot of memory. The crash means, that the memory is exhausted.

Either close the figures, if you do not need them anymore. Or reuse the existing figures, which would be much moire efficient. See e.g. clf.

[Victor Gimenez]

This loop for: p1 = 1:16 represents the corresponding EEG electrodes that are being used and p2 = 1:a_trials the epochs/trials in each electrode that are 785 and there is another nested loop similar this one next this until 780 representing epochs/events from other group, yes there are 12560 iterations going on and because it that I performed set(0,'DefaultFigureVisible','off'); before whole routine, so I am gonna put this clf to verify!! Thanks for the tip at the moment Jan!

[Victor Gimenez]

Hey Jan, I could able to solve it 1/3 I'd say, when the count variable was around 3341 my whole environment crashed again... but it was more far than before