Concatenation inside cell arrays

Dear all,

I have a cell array that is made up of two cell arrays of (1x60) dimensions. Each one of them cell arrays of different dimensions. However, these dimensions are identical in both of them. Again, each one of these inner cell arrays contain multiple double matrices of the same size, but different from their counterparts in the other cell array with one dimension. What I have just said is illustrated for clarification in the image below:

What I would like to do is to concatenate the inner-most matrices each to its corresponding one along their first dimension (concat(17x12 & 13x12) => 30x12) as shown above. That will typically produce a single (1x60) cell array as shown above. I know I can do this with very complicated and time consuming loops, however, I would like your help to make it as compact as possible.

Yours, Maad

Answer 1

[Jan]

This is easy and efficient with a loop. I do not see, why you assume that it is "very complicated and time consuming".

% Input cells: A, B
C = cell(size(A));
for k = 1:numel(C)
   a  = A{k};
   b  = B{k};
   ab = cell(size(a));
   for kk = 1:numel(ab)
     ab{kk} = [a{kk}, b{kk}];
   end
   C{k} = ab;
end

[Maad Ebrahim]

I have actually done that in a similar way already. And I have just thought that it could be done somehow using cell and matrix indexing only.

Thank you for your answer though. Appreciate it.

[Jan]

You are welcome. The pictures in your question are excellent. The problem is hard to explain in words, but it was easy to write the code just based on these images. +1 for your question.

[Maad Ebrahim]

Thanks for your nice words :)

Answer 2

[Tejeswar Yarlagadda]

I hope this might help you

let us say A is sub cell of B and A is again having single layer of sub cells

for example

A = {{[1;2;3];[5;6;7]},{[1;2;3],[5;6;7]};{[1,2,3];[5,6,7]},{[1,2,3],[5,6,7]}};

if you want to concatenate in

first direction

cellfun(@(x) cat(1,x{:}),A,'UniformOutput',false)
ans =
  2×2 cell array
    {6×1 double}    {6×1 double}
    {2×3 double}    {2×3 double}

second direction

cellfun(@(x) cat(2,x{:}),A,'UniformOutput',false)
ans =
  2×2 cell array
    {3×2 double}    {3×2 double}
    {1×6 double}    {1×6 double}