text: Q:
  
  in Numpy, how to zip two 2-D arrays?
  
  For example I have 2 arrays
  a = array([[0, 1, 2, 3],
             [4, 5, 6, 7]])
  b = array([[0, 1, 2, 3],
             [4, 5, 6, 7]])
  
  How can I zip a and b so I get
  c = array([[(0,0), (1,1), (2,2), (3,3)],
             [(4,4), (5,5), (6,6), (7,7)]])
  
  ?
  
  A:
  
  You can use dstack: 
  >>> np.dstack((a,b))
  array([[[0, 0],
          [1, 1],
          [2, 2],
          [3, 3]],
  
         [[4, 4],
          [5, 5],
          [6, 6],
          [7, 7]]])
  
  If you must have tuples:
  >>> np.array(zip(a.ravel(),b.ravel()), dtype=('i4,i4')).reshape(a.shape)
  array([[(0, 0), (1, 1), (2, 2), (3, 3)],
         [(4, 4), (5, 5), (6, 6), (7, 7)]],
        dtype=[('f0', '<i4'), ('f1', '<i4')])
  
  For Python 3+ you need to expand the zip iterator object. Please note that this is horribly inefficient:
  >>> np.array(list(zip(a.ravel(),b.ravel())), dtype=('i4,i4')).reshape(a.shape)
  array([[(0, 0), (1, 1), (2, 2), (3, 3)],
         [(4, 4), (5, 5), (6, 6), (7, 7)]],
        dtype=[('f0', '<i4'), ('f1', '<i4')])
  
  A:
  
  np.array([zip(x,y) for x,y in zip(a,b)])
  
  