On Mon, Oct 11, 2010 at 1:44 PM, Tom Pacheco <tomsli...@netp.org> wrote:
> your creating a 1d list > > this creates a 2d list > a=[[[]]*5 > > > >>> [0]*5 > [0, 0, 0, 0, 0] > >>> [[]]*5 > [[], [], [], [], []] > Don't do this. This actually just creates a list containing the same empty list 5 times: >>> a = [[]] * 5 >>> a [[], [], [], [], []] >>> a[0].append(1) >>> a [[1], [1], [1], [1], [1]] >>> a[1][0] = 2 >>> a [[2], [2], [2], [2], [2]] Chris gave a correct way to create a list of lists, using a list comprehension. Cheers, Ian
-- http://mail.python.org/mailman/listinfo/python-list
