Re: weakref, memory management and execution slow down in PyQt4

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Date	Tue, 09 Sep 2014 09:57:02 -0600
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Subject	Re: weakref, memory management and execution slow down in PyQt4
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On 09/09/2014 09:37 AM, Chris Angelico wrote:
> On Wed, Sep 10, 2014 at 1:32 AM, Michael Torrie <torriem@gmail.com> wrote:
>> Yes you're correct.  It is the equivalent.  But it always involves
>> lookup in the object's dictionary, which is big O order O(n log n)
>> complexity for each and every access.
> 
> Where do you get that figure from? A CPython dictionary is implemented
> as a hashtable, so algorithmic complexity of lookups ought to be O(1).

You're right, it is.  My mistake.  Guess the main issue is the overhead
of an additional function call.  A dict directly or a list directly may
me faster.

Anyway, I guess we're wandering in the weeds a bit as the original issue
is probably not related to his unorthodox choice of metaprogramming as a
data model.

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Re: weakref, memory management and execution slow down in PyQt4 Michael Torrie <torriem@gmail.com> - 2014-09-09 09:57 -0600

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