itertools.permutations
suggest changeitertools.permutations returns a generator with successive r-length permutations of elements in the iterable.
a = [1,2,3]
list(itertools.permutations(a))
# [(1, 2, 3), (1, 3, 2), (2, 1, 3), (2, 3, 1), (3, 1, 2), (3, 2, 1)]
list(itertools.permutations(a, 2))
[(1, 2), (1, 3), (2, 1), (2, 3), (3, 1), (3, 2)]if the list a has duplicate elements, the resulting permutations will have duplicate elements, you can use set to get unique permutations:
a = [1,2,1]
list(itertools.permutations(a))
# [(1, 2, 1), (1, 1, 2), (2, 1, 1), (2, 1, 1), (1, 1, 2), (1, 2, 1)]
set(itertools.permutations(a))
# {(1, 1, 2), (1, 2, 1), (2, 1, 1)}
Found a mistake? Have a question or improvement idea?
Let me know.
Table Of Contents