I want to sort an array, so it starts off at
order = [0,1,2,3,4,5] #loop around trying all columns`
and then will go through, trying all combinations of this so 1,2,3,4,5,0 etc, and stop once it has tried all of them.
Is there anyway to do this in python?
If you just want to "rotate" a list, have a look at the deque class:
>>> from collections import deque
>>> order = [0,1,2,3,4,5]
>>> order.sort() # ensure order is sorted
>>> q = deque(order)
>>> for _ in xrange(len(q)):
... q.rotate(-1)
... print q
...
deque([1, 2, 3, 4, 5, 0])
deque([2, 3, 4, 5, 0, 1])
deque([3, 4, 5, 0, 1, 2])
deque([4, 5, 0, 1, 2, 3])
deque([5, 0, 1, 2, 3, 4])
deque([0, 1, 2, 3, 4, 5])
>>>
If you mean all permutations, rather than the rotations in Dominic's answer:
import itertools
permutations = [ p for p in itertools.permutations(order) ]
There's 720 permutations in total so I won't print them :)
[p for p in <iterable>] <==> list(<iterable>) Converting an iterator to a list can be very expensive, especially for permutations, which would consume O(n!) memory. Yikes.
order.sort()works..rotationsor all thepermutations?