title: keeping track of indices change in numpy.reshape
body: <p>While using <code>numpy.reshape</code> in Python, is there a way to keep track of the change in indices?</p>
  
  <p>For example, if a numpy array with the shape <code>(m,n,l,k)</code> is reshaped into an array with the shape <code>(m*n,k*l)</code>; is there a way to get the initial index (<code>[x,y,w,z]</code>) for the current <code>[X,Y]</code> index and vice versa?</p>