On 20/03/2020 21:57, Barry wrote: > > >> On 20 Mar 2020, at 00:42, duncan smith <duncan@invalid.invalid> wrote: >> >> Bingo. Performance is indistinguishable from that of the list. Thread >> safety is unimportant (for my purposes), but the docs at >> https://docs.python.org/2/library/collections.html#collections.deque >> state "Deques support thread-safe, memory efficient appends and pops >> from either side of the deque with approximately the same O(1) > > I did a performance test of list vs sequel as a fifo that had 10k elements in > them. > Then I timed insert elements at the tail and popping from the head. > > Duque is 10x faster then list, rest run macOS python 3.8 > > Barry > >
Yes, I avoided the cost of popping elements from the head by just iterating over the list. So the timings came out very similar. But the deque allows me to remove those elements efficiently. It's also neat because it lets me switch from what is basically a breadth first search of a graph to a depth first search by simply changing popleft() to popright(). Cheers. Duncan -- https://mail.python.org/mailman/listinfo/python-list
