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Re: Complexity question on Python 3 lists

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Date Wed, 15 Feb 2012 10:35:25 -0800
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Subject Re: Complexity question on Python 3 lists
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On Wed, Feb 15, 2012 at 10:20 AM, Franck Ditter <franck@ditter.org> wrote:
> What is the cost of calling primes(n) below ? I'm mainly interested in
> knowing if the call to append is O(1), even amortized.
> Do lists in Python 3 behave like ArrayList in Java (if the capacity
> is full, then the array grows by more than 1 element) ?

Yes. Python lists aren't linked lists. list.append() resizes the
underlying array intelligently to give O(1) performance, although I
can't find any guarantee of this in the docs, but it is true in
practice for all major Python implementations.

Cheers,
Chris

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Thread

Complexity question on Python 3 lists Franck Ditter <franck@ditter.org> - 2012-02-15 19:20 +0100
  Re: Complexity question on Python 3 lists Chris Rebert <clp2@rebertia.com> - 2012-02-15 10:35 -0800
  Re: Complexity question on Python 3 lists Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-15 11:43 -0700
  Re: Complexity question on Python 3 lists Dave Angel <d@davea.name> - 2012-02-15 13:45 -0500
  Re: Complexity question on Python 3 lists Stefan Behnel <stefan_ml@behnel.de> - 2012-02-15 20:01 +0100
  Re: Complexity question on Python 3 lists Chris Rebert <clp2@rebertia.com> - 2012-02-15 11:11 -0800
  Re: Complexity question on Python 3 lists Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-02-15 15:28 -0500
  Re: Complexity question on Python 3 lists Terry Reedy <tjreedy@udel.edu> - 2012-02-15 16:41 -0500
  Re: Complexity question on Python 3 lists Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-15 15:54 -0700
  Re: Complexity question on Python 3 lists Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-16 00:41 +0000

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