How to construct an array with varying dimension?

I want to save some data using a "for loop". Within each iteration, I will get a 2D matrix (which I want to save). the size of the matrices is NOT the same, i.e. first 10*10, then 23*23, next 20*20 and so on (no pattern between the sizes). I clearly cannot use a 3D matrix to save the data since the third dimension is not constant. I cannot save them manually/separately either since there is a lot of 2D matrices (this is actually why i am putting it in a for loop). I also do NOT know the size of the largest 2D matrix.

what can I use to do the above? cell? structure?

tnx in advance

Answer 1

[Image Analyst]

Yes. Use a cell array. That's what it's meant for. See the FAQ for a good explanation and some good illustrative examples: http://matlab.wikia.com/wiki/FAQ#What_is_a_cell_array.3F

[ramin bba]

thanks, it helped a lot.

Answer 2

[Geoff Hayes]

A cell array would work well for this problem. Since you have a for loop, you have an idea of how many matrices you will need to save. Try the following:

 % size the cell array where n is the number of iterations in the for loop (and
 % the number of matrices to save)
 cellArray = cell(n,1);

 % iterate
 for k=1:n

   % do stuff

   % save kth matrix A to cell array
   cellArray{k} = A;

 end

And that is it - all matrices will be saved to the cellArray object.

[ramin bba]

thanks.