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How to cell array of string to 3D matrix?

I have a cell array with size 200x1 with each cell having a string array 12000x1 cell. Example of string array with size 12000x1 will be in the attached file. How can i convert this cell into a 3d numeric matrix array of size 12000x5x200 ?? Thank you in advance.

  2 Comments

"I have a cell array with size 200x1 with each cell having a string array 12000x1 cell"
But what you uploaded is a 12000x1 cell array, where each cell contains a character vector.:
>> size(AB)
ans = 12000 1
>> all(cellfun('isclass',AB,'char'))
ans = 1
Your question and your supplied data do not match.
I am sorry. please refer to the new attached file.

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1 Answer

Answer by Stephen Cobeldick on 15 Nov 2018
Edited by Stephen Cobeldick on 15 Nov 2018
 Accepted Answer

This converts your supplied cell array (attached) into a numeric array:
>> C = cellfun(@(s)sscanf(s,'%f'),AB,'uni',0);
>> A = cat(3,C{:});
>> size(A)
ans =
5 1 12000
Note that your data description does not match the data in your .mat file.

  2 Comments

Two methods that work with the data in your second example file.
Method one: cellfun and cellmat:
>> load Example_of_cell2.mat
>> F = @(s) sscanf(s,'%f',[1,Inf]);
>> A = cell2mat(cellfun(F,cat(3,BB{:}),'uni',0));
>> size(A)
ans =
12000 5 200
Method two: sprintf, reshape and permute:
>> C = [BB{:}];
>> B = sscanf(sprintf('%s\v',C{:}),'%f');
>> B = permute(reshape(B,[5,12000,200]),[2,1,3]);
>> size(B)
ans =
12000 5 200
Method two is quite possibly faster. Comparing the outputs:
>> isequal(A,B)
ans = 1
It works. Thank you so much.

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