If your matrices are not together in a cell array, e.g. they're individually numbered matrices, then
- don't do that!
- fix the problem by putting them together in a cell array:
c = {M1, M2, M3, ....}
it is then trivial to reshape/transform that cell array and generate the full matrix you want:
c = reshape(c, 3, 3); %reshape the cell array in a 3x3 grid
c = rot90(c); %rotate 90 degrees anticlockwise
result = cell2mat(c); %concatenate all into one matrix
