Shuffle a numpy array

Question

I have a 2-d numpy array that I would like to shuffle. Is the best way to reshape it to 1-d, shuffle and reshape again to 2-d or is it possible to shuffle without reshaping?

Answer 1

You can tell np.random.shuffle to act on the flattened version:

>>> a = np.arange(9).reshape((3,3))
>>> a
array([[0, 1, 2],
       [3, 4, 5],
       [6, 7, 8]])
>>> np.random.shuffle(a.flat)
>>> a
array([[3, 5, 8],
       [7, 6, 2],
       [1, 4, 0]])