I have a loop that evaluates a matrix X for each scenario. The size of this matrix X changes at each iteration, and the values too. I would like to make a structure X.1, X.2 etc to X.(n), and save the result X. When I do eval(['[Z.SET'num2str(J) ']= (Xtmp);']); X.1 gets overwritten by X.2, what I mean is that at first I have X.1 with the desired X matrix, but at the next loop, X.1 is no longer there and there is X.2 (with the corresponding X matrix). How can I “save” the X.1 so that it doesn’t get overwritten?