At a minimum, num2str(1:m) isn't going to generate a cell vector of strings, which is what the row names need to be. For example:
>> num2str(1:5)
ans =
1 2 3 4 5
However, this will:
>> strsplit(num2str(1:5),' ')
ans =
'1' '2' '3' '4' '5'
