how to transfer a 3D variable into a row in an excel file?

Hello all,

As shown in the attached document, I have "data"(EEG data) in the form of "numberOf_Electorrdes * numberOf_Points * rial" single variable.

How Can I write it in an excel file in one row (each row is one subject) and with as many columns as the number of electordes? I tired writetable(struct2table(EEG.data), 'data.xlsx' but I got this error "Input structure must be a scalar structure.

I have also the "lable of each electrode" and I need each number to go under the right channel.

EEGData= EEG.data;

ch_lables=EEG.chanlocs.labels; % I uesed this and only the first lable is shown?

I appreciate your help in advance.

Zahra

[Sudheer Bhimireddy]

Did you check your variable EEGData size and type? The variable you are showing and the excel file below seems to have different channel labels.

[Elaheh]

The excel file was just used as an example. The number of channels is different for each person becuase 
I delete channels that are too noisy. so the number differs. In this example file, the size is :

 size(EEGData)

ans =

    62    75    14
    
    > class(EEGData)

ans =

    'single'

[dpb]

Need clarification on what you're asking to do -- the 3D array is nElectrodes X nPoints x nTrials for some observation?

What do you want out of this 3D array to go where into an output record that is a vector observation? For

data(1:nElectrodes,j,k)

one would have nElectrodes observations of the j,k-th observation; there would then be nPoints*nTrials rows to output the full data array -- and one would have to pick the order in which to iterate over j,k to know in which order the data were stored...one would also need to save what those two dimensions were to avoid potentially ambigous interpretation of using said data.

As always, showing an actual example of possible input and expected output with illustration of how the result follows from the input would make things much more clear.

Answer 1

[Image Analyst]

In general, you can make a row vector out of your 3-D variable like this:

rowVector = array3d(:)';
% Now write to Excel
xlswrite(filename, rowVector, sheetName, 'A1');

array3d(:) turns it into a column vector, and then the apostrophe transposes it into a row vector.

[Elaheh]

Thank you for your response. I got this error :

The specified data range is invalid or too large to write to the specified file

format. Try writing to an XLSX file and use Excel A1 notation for the range

argument, for example, ‘A1:D4’.

[Image Analyst]

Elaheh, this script works just fine for me:

fprintf('Beginning to run %s.m ...\n', mfilename);
array3d = randi(255, 2, 4, 2) % Create 3-D matrix.
rowVector = array3d(:)'
sheetName = 'Results';
% Now write to Excel
fileName = 'deleteme.xlsx';
xlswrite(fileName, rowVector, sheetName, 'A1');
if ispc
	winopen(fileName)
end
fprintf('Done running %s.m ...\n', mfilename);

Perhaps your 3-D array is so huge it can't fit on one row in Excel. What does this say:

size(yourArray)
numel(yourArray)

Answer 2

[Sulaymon Eshkabilov]

Hi,

a simple solution might be this one:

for ii=1:14  % EEGData has 14 layers
    SH=strcat('Sheet', num2str(ii));
    xlswrite('EEGData_ALL.xlsx', EEGData(:,:,ii), SH);  % Note that you will have 14 seprate sheets of data 
end

[Elaheh]

Thank you so much.

It worked.

[Image Analyst]

How does it work? It does not write your entire 3-D array out to a single row in Excel as you asked.