# How do you vertically concatenate the rows of a cell array consisting of vectors of numbers?

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L'O.G. on 30 Mar 2022
Commented: Simon Chan on 30 Mar 2022
I want to vertically concatenate the elements of a cell array so that, for example, an array that is 3 x 9 becomes 1 x 9. How do I do that? The following concatenates everything into one dimension, which isn't what I want:
vertcat(cellarray{:});
the cyclist on 30 Mar 2022
What you want to do is not clear to me. Can you upload the cell array (using the paperclip icon in the INSERT section of the toolbar), or perhaps just write code here to define an smaller (like 3x2) input, and what you expect the output to be?
The best method will likely depend on whether the cell elements are numeric, strings, character arrays, etc.
L'O.G. on 30 Mar 2022
Edited: L'O.G. on 30 Mar 2022
Each element of the cell array contains an N x 1 vector where N is not necessarily the same for each vector and the elements of the vector are numbers with double precision.

per isakson on 30 Mar 2022
Example
m = magic(3);
m = [m,m,m];
cac = num2cell(m); % sample data
arrayfun( @(ix) vertcat(cac{:,ix}), [1:9], 'uni',false )
ans = 1×9 cell array
{3×1 double} {3×1 double} {3×1 double} {3×1 double} {3×1 double} {3×1 double} {3×1 double} {3×1 double} {3×1 double}
Is this what you look for?
L'O.G. on 30 Mar 2022
Edited: L'O.G. on 30 Mar 2022
Yes, beautiful! Thanks! I didn't know about arrayfun.

Simon Chan on 30 Mar 2022
Tru the following:
cellfun(@(x) cell2mat(x),num2cell(a,1),'uni',0)
L'O.G. on 30 Mar 2022
Edited: L'O.G. on 30 Mar 2022
@Simon Chan What is a?
Simon Chan on 30 Mar 2022
a is the 3x9 cell array

Walter Roberson on 30 Mar 2022
Output = arrayfun(@(ColIdx) vertcat(YourCell{:,ColIdx}), 1:size(YourCell,2), 'uniform', 0);

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