title: TypeError: Extracting rows of matrix into new matrix
body: <p>Suppose I have an initialised zero matrix:</p>
  
  <pre><code> A = zeros(m,n)
  </code></pre>
  
  <p>And I also have another matrix, B, which has dimension kxn, where k>=m. We want to extract rows p through to q of B and make that A. We have set the dimension of the matrix of A (assumed) to be the same as q-p+1.
       When I try A[p:q,:] = B[p:q,:], Python gives me an error! How can I solve this?</p>
  
  <p>e.g. Suppose we have:</p>
  
  <pre><code> Q = ones((7,4))
   A = zeros((5,4))
   %want rows 2 to 6 of Q
   A = Q[1:5,]
  </code></pre>