# [Numpy-discussion] lists of zeros and ones

Joe Kington jkington at wisc.edu
Fri Mar 19 11:17:41 EDT 2010

```See itertools.permutations (python standard library)

e.g.
In [3]: list(itertools.permutations([1,1,0,0]))
Out[3]:
[(1, 1, 0, 0),
(1, 1, 0, 0),
(1, 0, 1, 0),
(1, 0, 0, 1),
(1, 0, 1, 0),
(1, 0, 0, 1),
(1, 1, 0, 0),
(1, 1, 0, 0),
(1, 0, 1, 0),
(1, 0, 0, 1),
(1, 0, 1, 0),
(1, 0, 0, 1),
(0, 1, 1, 0),
(0, 1, 0, 1),
(0, 1, 1, 0),
(0, 1, 0, 1),
(0, 0, 1, 1),
(0, 0, 1, 1),
(0, 1, 1, 0),
(0, 1, 0, 1),
(0, 1, 1, 0),
(0, 1, 0, 1),

(0, 0, 1, 1),
(0, 0, 1, 1)]

Hope that helps,
-Joe

On Fri, Mar 19, 2010 at 9:53 AM, gerardob <gberbeglia at gmail.com> wrote:

>
> Hello, i would like to produce lists of lists 1's and 0's.
>
> For example, to produce the list composed of:
>
> L = [[1,0,0,0],[0,1,0,0],[0,0,1,0],[0,0,0,1]]
>
> I just need to do the following:
>
> n=4
> numpy.eye(n,dtype=int).tolist()
>
> I would like to know a simple way to generate a list containing all the
> lists having two 1's at each element.
>
> Example, n = 4
> L2 = [[1,1,0,0],[1,0,1,0],[1,0,0,1],[0,1,1,0],[0,1,0,1],[0,0,1,1]]
>
> Any ideas?
> Thanks.
>
>
>
>
>
>
>
> --
> View this message in context:
> http://old.nabble.com/lists-of-zeros-and-ones-tp27950978p27950978.html
> Sent from the Numpy-discussion mailing list archive at Nabble.com.
>
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