On Mon, Jan 17, 2022 at 11:18:13PM +0900, Inada Naoki wrote:
> On Mon, Jan 17, 2022 at 8:49 PM Steven D'Aprano <[email protected]> wrote:
> >
> > On Mon, Jan 17, 2022 at 08:04:50PM +0900, Inada Naoki wrote:
> >
> > > Name lookup is faster than building set in most case.
> > > So I don't think cost to look name up is important at all.
> >
> > But the cost to look up the name is *in addition* to building the set.
> >
>
> I meant it is negligible so we can just ignore it while this discussion.
On my computer, the name lookup is almost a quarter of the time to build
a set:
[steve ~]$ python3.10 -m timeit "frozenset"
10000000 loops, best of 5: 24.4 nsec per loop
[steve ~]$ python3.10 -m timeit "{1, 2, 3, 4, 5}"
2000000 loops, best of 5: 110 nsec per loop
and about 10% of the total time:
[steve ~]$ python3.10 -m timeit "frozenset({1, 2, 3, 4, 5})"
1000000 loops, best of 5: 237 nsec per loop
If I use a tuple instead of the set, it is about 12% of the total time:
[steve ~]$ python3.10 -m timeit "frozenset((1, 2, 3, 4, 5))"
2000000 loops, best of 5: 193 nsec per loop
So not negligible.
--
Steve
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