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Re^4: Best method to diff very large array efficiently

by LanX (Canon)
on Nov 25, 2013 at 22:51 UTC ( #1064329=note: print w/ replies, xml ) Need Help??


in reply to Re^3: Best method to diff very large array efficiently
in thread Best method to diff very large array efficiently

Well I think it depends on the testcase, I tried random numbers in an intervall 1..1e6 like BUK did.

See my benchmark here RFC extending Benchmark.pm to facilitate CODEHASHREF

Maybe I did something wrong ...

... but I'm not to keen to continue, IMHO all approaches are already fast enough.

Cheers Rolf

( addicted to the Perl Programming Language)

update

oops undef @hash{@arr} is significantly faster than @hash{@arr}=()


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Re^5: Best method to diff very large array efficiently
by Kenosis (Priest) on Nov 25, 2013 at 23:00 UTC

    Well I think it depends on the testcase...

    Indeed, I think you're correct. And since the OP had some very specific specs, the qualified language "based upon benchmarking for this task" was used when characterizing the benchmarking results.

    It was surprising to see how 'slow' Set::Scalar was, in this case. It may, in part, have to do with it maintaining the object-accessible universe of numbers from which the diff is calculated -- also accessed via the returned object.


    update

    Yes, undef @diff3{@arr_1} makes the OP's original solution faster than using @diff3{@arr_1} = (). Have updated the benchmarking. Thank you, again.

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