Subtuples of a tuple [duplicate]

Question

How do I generate

[(0,), (1,), (2,), (0,1), (0,2), (1,2), (0,1,2)]

programmatically (that is, without writing everything out by hand)? That is, a list of all nonempty subtuples of the tuple (0,1,2).

(Note this is not asking for subsets but subtuples.)

Answer 1

>>> from itertools import combinations
>>> t = (0, 1, 2)
>>> print [subset for r in range(1,4) for subset in itertools.combinations(t,r)]
[(0,), (1,), (2,), (0, 1), (0, 2), (1, 2), (0, 1, 2)]

Itertools is a powerful resource. You should check out the documentation

Answer 2

You can use the powerset() recipe and remove the empty set:

from itertools import chain, combinations

def powerset(iterable):
    "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)"
    s = list(iterable)
    return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))

as follows:

In [3]: [ss for ss in powerset([0,1,2]) if ss]
Out[3]: [(0,), (1,), (2,), (0, 1), (0, 2), (1, 2), (0, 1, 2)]