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Re: How to remove item from heap efficiently?

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From "Sven R. Kunze" <srkunze@mail.de>
Newsgroups comp.lang.python
Subject Re: How to remove item from heap efficiently?
Date Tue, 12 Jan 2016 17:18:50 +0100
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On 12.01.2016 03:48, Cem Karan wrote:
>
> Jumping in late, but...
>
> If you want something that 'just works', you can use HeapDict:
>
> http://stutzbachenterprises.com/
>
> I've used it in the past, and it works quite well.  I haven't tested its asymptotic performance though, so you might want to check into that.

Thanks for replying here. I've come across these types of 
wrappers/re-implementations of heapq as well when researching this issue. :)

Unfortunately, they don't solve the underlying issue at hand which is: 
"remove item from heap with unknown index" and be efficient at it (by 
not using _heapq C implementation).


So, I thought I did another wrapper. ;) It at least uses _heapq (if 
available otherwise heapq) and lets you remove items without violating 
the invariant in O(log n). I am going to make that open-source on pypi 
and see what people think of it.

Best,
Sven

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Re: How to remove item from heap efficiently? "Sven R. Kunze" <srkunze@mail.de> - 2016-01-12 17:18 +0100

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