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    <p>You <strong>cannot</strong> remove different rows from a 3D array, you can remove 'floors', or layers or 'walls'. (If you imagine a building by layer I intend a vertical and perpendicular plane to your point of vision while a wall is a vertical plane along your point of vision).</p> <p>You <strong>should not</strong> store numeric data in this way, i.e. one number per cell. You incur in a 112 bytes <strong>overhead</strong> per cell when a scalar double is only 8 bytes. </p> <p>According to the sparsity pattern I can observe from your example, you might benefit by converting it into a <strong>sparse</strong> array which still reference against the original size of the array but without storing <code>0</code> or <code>[]</code>. However, sparse arrays are only 2D, where the additional layers (from a 3rd dimension) are stored consecutively along the 2nd dimension. </p> <p>A simplified version of your example will clarify:</p> <pre><code>val(:,:,1) = { [20] [] [] [] [ 0] [] [] [] [ 0] [] [] [] [] [] [] []}; val(:,:,2) = { [ 34225] [ 215] [ 0] [ 0] [ 85200] [ 545] [ 0] [ 0] [ 65074] [ 190] [ 1000] [ 0] [] [] [] [] }; % Find non-zero empty elements (0s will be discarded automatically) [r,c] = find(~cellfun('isempty',val)); % Convert to sparse (note the coordinates are only 2D) sp = sparse(r,c,[val{:}]); sp = (1,1) 20 (1,5) 34225 (2,5) 85200 (3,5) 65074 (1,6) 215 (2,6) 545 (3,6) 190 (3,7) 1000 % Convert to full to see what happened with the 3rd dimension full(sp) ans = 20 0 0 0 34225 215 0 0 0 0 0 0 65074 190 0 0 0 0 0 0 85200 545 1000 0 </code></pre> <p>you can see that the second layer has been concatenated horizontally (along columns). You can use reshape if you need to recover the 3D.</p> <p>The advantage of <code>val</code> vs <code>sp</code> is in the reduced storage:</p> <pre><code> Name Size Bytes Class Attributes sp 3x8 200 double sparse val 4x4x2 3704 cell </code></pre>
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    1. PODeleting empty rows in a 3D cell array in Matlab
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    1. COWow, thanks a lot, it was a very different solution. Nevertheless, in my cell I have some dates, not only numeric data. Also, I need my ZEROS, because they are valuable information too. I dont need the FULLY EMPTY ROWS, only. But thanks a lot for your efforts
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      1. USLuiz
    2. CODates can be stored as serial numbers, and I recommend to do that with `datenum()`. Good remark about the zeros.
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      1. USOleg
 

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