xor operator

[Peter J. Holzer]

On 2023-11-15 12:26:32 +0200, Dom Grigonis wrote:
> 
> Thank you,
> 
> 
> test2 = [True] * 100 + [False] * 2
> test2i = list(range(100))
> 
> %timeit len(set(test2i)) == 1   # 1.6 µs ± 63.6 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)
> %timeit all(test2)              # 386 ns ± 9.58 ns per loop (mean ± std. dev. of 7 runs, 1,000,000 loops each)
> 
> test2s = set(test2i)
> %timeit len(test2s) == 1        # 46.1 ns ± 1.65 ns per loop (mean ± std. dev. of 7 runs, 10,000,000 loops each)
> 
> If you pre-convert to set it is obviously faster. However, set
> operation is most likely going to be part of the procedure. In which
> case it ends up to be significantly slower.

Obviously, if you convert a list to a set just to count the elements
it's going to be slow. My suggestion was to use the set *instead* of the
list. I don't know whether that's possible in your situation, because
you haven't told us anything about it. All I'm suggesting is taking a
step back and reconsider your choice of data structure.

        hp
-- 
   _  | Peter J. Holzer    | Story must make more sense than reality.
|_|_) |                    |
| |   | hjp at hjp.at         |    -- Charles Stross, "Creative writing
__/   | http://www.hjp.at/ |       challenge!"
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