Matlab: Matrix multiplication of many matrices in cell arrays -


i have cell array size 1x200x201, in each cell 2x2 matrix. need multiply matrices in way resulting matrix: 2x2x201. means: cell_m{1,1,1}* cell_m{1,2,1}*cell_m{1,3,1}*... , on 200, , same 201 ( cell_m{1,1,2}* cell_m{1,2,2}*cell_m{1,3,2}*... ). cell arrays way handling data. effective way multiplications?

floating-point matrix multiplication not associative in general, a*b*c*d ambiguous. in code assume looking ((a*b)*c)*d

d=size(cell_m);  p = cell(d(1), 1, d(3));  p(:)={eye(2)};  k=1:d(2),      p = cellfun(@mtimes, p(:,1,:), cell_m(:,k,:), 'uniformoutput', false);  end p = squeeze(p);

now p cell array of 201 elements each element 2-by-2 matrix.


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