title: "TypeError: len() of unsized object" when using insert for arrays
body: <p>objective: to insert a row in the array at a given index position (i)</p>
  
  <p>Language used: python with numpy library</p>
  
  <p>example:</p>
  
  <pre><code>i=2.0;
  a=array([[1,2,3],[2,3,4],[3,4,5],[6,7,8]],dtype=float);
  a=insert(a,i,[-1,-1,-1],axis=0);
  </code></pre>
  
  <p>this gave the error: <code>TypeError: len() of unsized object</code>.</p>
  
  <p>Any ideas?</p>