matlab code error - Subscript indices must either be real positive integers or logicals.*

Hi,

Would anybody know why I am getting the following error after the code below executes a couple of times (about 20 times).

??? Subscript indices must either be real positive integers or logicals.

I've had no problems with it up until today.

Thank you

   for j=1:5000
  transC = [zeros(size(T,1),1), cumsum(T,2)];
  n = 10000;
  states = zeros(1,n); %storage of states
  states(1) = 8; %start at state 1 (or whatever)
  rr = rand(1,n);
  for ii = 2:n
  [~,states(ii)] = histc(rr(ii),transC(states(ii-1),:));
  end
  states=states';
  states = convert(states, 2);
  baseFileName = sprintf('%d.xls', j);
  fullExcelFileName = fullfile('C:\raw bin 2 data\', baseFileName); % yourFolder can be pwd if you want.
  xlswrite(fullExcelFileName ,[states],'Sheet1', 'A1');
  end

[Walter Roberson]

Which line is it ocuring on?

Answer 1

[per isakson]

The debugger will tell you. Put the code in a function. Execute

    dbstop if error

in the command window. Run your function. Execution will stop just before the error is thrown. Inspect the values of the variables involved.

Answer 2

[Image Analyst]

You initialize states to all zeros. When it comes time to use it, inside transC, states(ii-1), which is states(1) when ii = 2, is still zero, so you are trying to get transC(0), and that causes an error.

[Walter Roberson]

No, John has states(1) = 8

[John]

Hi,

I got it working again by restarting matlab. If it happens again I will use the debugger.

Thanks for the comments.