Random selection of a member's location in a nested cell of cells: Matlab

Question

I have a nested cell of cells like the one below:

CellArray={1,1,1,{1,1,1,{1,1,{1,{1 1 1 1 1 1 1 1}, 1,1},1,1},1,1,1},1,1,1,{1,1,1,1}};

I need to randomly pick a location in CellArray. All members' locations of CellArray must have same chances to be chosen in the random selection process. Thanks.

Answer 1

You can capture the output of the celldisp function. Then use regex to extrcat indices:

s=evalc('celldisp(CellArray,'''')');
m = regexp(s, '\{[^\=]*\}', 'match');

• Thanks to @excaza that suggested a clearer use of regexp

Result:

m =
{
  [1,1] = {1}
  [1,2] = {2}
  [1,3] = {3}
  [1,4] = {4}{1}
  [1,5] = {4}{2}
  [1,6] = {4}{3}
  [1,7] = {4}{4}{1}
  [1,8] = {4}{4}{2}
  [1,9] = {4}{4}{3}{1}
  [1,10] = {4}{4}{3}{2}{1}
  [1,11] = {4}{4}{3}{2}{2}
  [1,12] = {4}{4}{3}{2}{3}
  [1,13] = {4}{4}{3}{2}{4}
  [1,14] = {4}{4}{3}{2}{5}
  [1,15] = {4}{4}{3}{2}{6}
  [1,16] = {4}{4}{3}{2}{7}
  [1,17] = {4}{4}{3}{2}{8}
  [1,18] = {4}{4}{3}{3}
  [1,19] = {4}{4}{3}{4}
  [1,20] = {4}{4}{4}
  [1,21] = {4}{4}{5}
  [1,22] = {4}{5}
  [1,23] = {4}{6}
  [1,24] = {4}{7}
  [1,25] = {5}
  [1,26] = {6}
  [1,27] = {7}
  [1,28] = {8}{1}
  [1,29] = {8}{2}
  [1,30] = {8}{3}
  [1,31] = {8}{4}
}

Use randi to select an index:

m{randi(numel(m))}