问题
I have a input like
A = [2,0,1,3,2,2,0,1,1,2,0].
Following I remove all the duplicates by
A = list(Set(A))
A is now [0,1,2,3]. Now I want all the pair combinations that I can make with this list, however they do not need to be unique... thus [0,3] equals [3,0] and [2,3] equals [3,2]. In this example it should return
[[0,1],[0,2],[0,3],[1,2],[1,3],[2,3]]
How do I achieve this? I looked in the iteratools lib. But couldn't come up with a solution.
回答1:
>>> A = [2,0,1,3,2,2,0,1,1,2,0]
>>> A = sorted(set(A)) # list(set(A)) is not usually in order
>>> from itertools import combinations
>>> list(combinations(A, 2))
[(0, 1), (0, 2), (0, 3), (1, 2), (1, 3), (2, 3)]
>>> map(list, combinations(A, 2))
[[0, 1], [0, 2], [0, 3], [1, 2], [1, 3], [2, 3]]
>>> help(combinations)
Help on class combinations in module itertools:
class combinations(__builtin__.object)
| combinations(iterable, r) --> combinations object
|
| Return successive r-length combinations of elements in the iterable.
|
| combinations(range(4), 3) --> (0,1,2), (0,1,3), (0,2,3), (1,2,3)
|
| Methods defined here:
|
| __getattribute__(...)
| x.__getattribute__('name') <==> x.name
|
| __iter__(...)
| x.__iter__() <==> iter(x)
|
| next(...)
| x.next() -> the next value, or raise StopIteration
|
| ----------------------------------------------------------------------
| Data and other attributes defined here:
|
| __new__ = <built-in method __new__ of type object>
| T.__new__(S, ...) -> a new object with type S, a subtype of T
来源：https://stackoverflow.com/questions/5560479/get-sorted-combinations