Remove duplicated lists in list of lists in Python
list, python, python-2.7, set
Solution
(ab)using side-effects version of a list comp:
seen = set()
[x for x in g if frozenset(x) not in seen and not seen.add(frozenset(x))]
Out[4]: [[1, 2, 3], [9, 0, 1], [4, 3, 2]]
For those (unlike myself) who don't like using side-effects in this manner:
res = []
seen = set()
for x in g:
x_set = frozenset(x)
if x_set not in seen:
res.append(x)
seen.add(x_set)
The reason that you add `frozenset`s to the set is that you can only add hashable objects to a `set`, and vanilla `set`s are not hashable.
Problem
I've seen some questions here very related but their answer doesn't work for me. I have a list of lists where some sublists are repeated but their elements may be disordered. For example `g = [[1, 2, 3], [3, 2, 1], [1, 3, 2], [9, 0, 1], [4, 3, 2]]` The output should be, naturally according to my question: `g = [[1,2,3],[9,0,1],[4,3,2]]` I've tried with `set` but only removes those lists that are equal (I thought It should work because sets are by definition without order). Other questions i had visited only has examples with lists exactly duplicated or repeated like this: Python : How to remove duplicate lists in a list of list?. For now order of output (for list and sublists) is not a problem.