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arraysmatlabmatrixcell-array

How to add rows of 3D cell

I have 3-D (60x72x29) cell arrays with numbers inside, and I want to add the rows across the 3rd dimension so that the resulting cell size should be (60x72). Is there any elegant way to do this?

Solution

  • The elegant way is to not use a cell array to hold multi-dimensional numeric data where each element only contains a scalar. MATLAB is optimized for dealing with multi-dimensional numeric arrays so you should convert your data to that format using cell2mat.

    Once it is a multi-dimensional numeric array, you can use sum combined with the second input which specifies the dimension along which to perform the operation.

    data = cell2mat(old_data);
S = sum(data, 3);

    If you really need a cell array back, you can use num2cell on the result to turn it back into a cell array

    C = num2cell(S);

    Update

    It looks like your initial data is a cell array of strings. If that's the case, you can instead use str2double convert the cell array of strings to a numeric array

    data = str2double(old_data);
S = sum(data, 3);