title: MATLAB: Using "regexp" for filtering letters and digits
body: <p>It's a simple question, but I just can't deal with regexp and after couple hours of trying I'm hoping you can help me.</p>
  
  <p>I have program a function that scans a string and starts specific operations depending on the cases and digits in the input-string.</p>
  
  <p>First I scan the input via textscan, take it into a vector via {} and extract the size. Then I want to have in the first column the cases and in the second column the digits. </p>
  
  <pre><code>%split String spaces 
  Zelle = textscan(trafostr, '%s');
  %save in Vector
  nZelle = Zelle{1,1};
  [z s] = size(nZelle);
  
  %set Startermatrix
  nmatrix = eye(3);
  
  for i=1:z;
      nString(i,1) = num2str(nZelle{i,1}, '%f');
  
  
  nString(i,1) = num2str(nZelle{i,1}, '%f');
  </code></pre>