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Re: Are there performance concerns with popping from front of long lists vs. the end of long lists?

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From Terry Reedy <tjreedy@udel.edu>
Subject Re: Are there performance concerns with popping from front of long lists vs. the end of long lists?
Date Sun, 22 Jun 2014 14:33:23 -0400
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On 6/22/2014 2:03 PM, python@bdurham.com wrote:
> Should I have any performance concerns with the index position used to
> pop() values off of large lists?

Yes. While performance is generally not part of the language 
specification, in CPython seq.pop(i) is O(len(seq)-i)

> In other words, should pop(0) and pop() be time equivalent operations
> with long lists?

No. If you want this, use collections.deque.


-- 
Terry Jan Reedy

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Re: Are there performance concerns with popping from front of long lists vs. the end of long lists? Terry Reedy <tjreedy@udel.edu> - 2014-06-22 14:33 -0400

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