title: What is Complex scalar type invalid as index value
body: <p>I am using Octave on Linux to do some basic Matlab computations and I am getting the error mentioned in the title for the following piece of code:</p>
  
  <pre><code>for a = i:n
   aux = U(j,a)/U(a,a);
   % L(a,i) = aux;
  end
  </code></pre>
  
  <p>I would like to mention that U is an n by n matrix and i is the index from another outer loop.</p>
  
  <p>Thanks,
  Daniel.</p>