in reply to Re^6: Divide array of integers into most similar value halves
in thread Divide array of integers into most similar value halves

Grr! Intersection & difference of arrays is something that ought to be in core.

Looked in List::MoreUtils to no avail.

I looked at cpan and downloaded Array::Utils but it can't handle duplicates.

Looked at List::Compare, but it comes complete with the kitchen sink & waste disposal (aliased as Belfast Sink & waste bin) and calculates 20 different things under the guise of "initalising".

Could you post an example of input array and expected outputs please.

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  • Comment on Re^7: Divide array of integers into most similar value halves

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Re^8: Divide array of integers into most similar value halves
by Pepe (Sexton) on Sep 04, 2008 at 16:04 UTC
    Sure!!! If
    @array = (40,17,40,30,40,25,40); is given

    something like

    @subarray1 = (40,40,30)
    @subarray2 = (40,40,17,25)

    should be returned.

    I guess you already have your own sources, but for intersection of arrays I always use a function from PerlFAQ 4:
    @union = @intersection = @difference = ();
    %count = ();
    foreach $element (@array1, @array2) { $count{$element}++ }
    foreach $element (keys %count) {
        push @union, $element;
        push @{ $count{$element} > 1 ? \@intersection : \@difference }
+, $element;
        }

    [download]

    Let me know if you need more examples, or what kind of them are you looking for
[reply]
[d/l]
[reply]
[d/l]
        Nice,

        But I found some cases (very few, like 0.001%) where it does not work, ie. @array=(43,44,43);
        It would return (43,43) and (43,44).
        Don't bother if you feel is gonna be a big problem. It's already good and I can just use it in combination with the other scripts that have been dropped in the conversation and choose the best answer.
        My problem is I can't modify it myself due to my low understanding of the code.
        Grrrr...someday.

        Thanks a lot.
        Cheers.
        Pepe.

        I know about FAQ code, but it's very convenient if you can spend the extra computing time and memory, but not the programming time.

[reply]

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