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Re: Python is not bad ;-)

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Date Sat, 2 May 2015 18:53:24 +0300
Subject Re: Python is not bad ;-)
From Joonas Liik <liik.joonas@gmail.com>
Cc Python <python-list@python.org>
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Balancing of trees is kind of irrelevant when "tree" means "search space"
no?
And you definitely dont need to keep the entire tree in memory at the same
time.

By cropping unsuitable branches early (and not keeping the entire tree in
memory)
it is quite easy to have more than 1000 of call stack and still have
reasonable
preformance. (some/many nodes have 0 or 1 children)

Also should not-running-out-of-call-stack really be the main reason to
balance trees?
That sounds like an optimisation to me ..

On 2 May 2015 at 18:45, Ian Kelly <ian.g.kelly@gmail.com> wrote:

> On Sat, May 2, 2015 at 5:42 AM, Marko Rauhamaa <marko@pacujo.net> wrote:
> > Christian Gollwitzer <auriocus@gmx.de>:
> >
> >> That's why I still think it is a microoptimization, which helps only
> >> in some specific cases.
> >
> > It isn't done for performance. It's done to avoid a stack overflow
> > exception.
>
> If your tree is balanced, then the number of items you would need to
> have to get a stack overflow exception would be approximately 2 **
> 1000, which you can't possibly hope to fit into memory.
>
> If your tree is unbalanced and you're getting a stack overflow
> exception, then maybe you should think about balancing it.
> --
> https://mail.python.org/mailman/listinfo/python-list
>

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Thread

Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 09:07 +0200
  Re: Python is not bad ;-) Ben Finney <ben+python@benfinney.id.au> - 2015-04-30 19:10 +1000
    Re: Python is not bad ;-) Marko Rauhamaa <marko@pacujo.net> - 2015-04-30 13:16 +0300
      Re: Python is not bad ;-) Chris Angelico <rosuav@gmail.com> - 2015-04-30 20:52 +1000
      Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 13:30 +0200
        Re: Python is not bad ;-) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-01 17:03 +1000
          Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-01 09:47 +0200
          Re: Python is not bad ;-) Christian Gollwitzer <auriocus@gmx.de> - 2015-05-01 19:56 +0200
          Re: Python is not bad ;-) Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-05-02 19:44 +1200
          Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-02 10:26 +0200
            Re: Python is not bad ;-) Marko Rauhamaa <marko@pacujo.net> - 2015-05-02 12:10 +0300
              Re: Python is not bad ;-) Chris Angelico <rosuav@gmail.com> - 2015-05-02 19:25 +1000
                Re: Python is not bad ;-) Marko Rauhamaa <marko@pacujo.net> - 2015-05-02 12:58 +0300
                Re: Python is not bad ;-) Dave Angel <davea@davea.name> - 2015-05-02 06:22 -0400
                Re: Python is not bad ;-) Chris Angelico <rosuav@gmail.com> - 2015-05-02 20:42 +1000
                Re: Python is not bad ;-) Christian Gollwitzer <auriocus@gmx.de> - 2015-05-02 13:07 +0200
                Re: Python is not bad ;-) Chris Angelico <rosuav@gmail.com> - 2015-05-02 21:21 +1000
                Re: Python is not bad ;-) Christian Gollwitzer <auriocus@gmx.de> - 2015-05-02 13:32 +0200
                Re: Python is not bad ;-) Marko Rauhamaa <marko@pacujo.net> - 2015-05-02 14:42 +0300
                Re: Python is not bad ;-) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 09:45 -0600
                Re: Python is not bad ;-) Chris Angelico <rosuav@gmail.com> - 2015-05-03 01:55 +1000
                Re: Python is not bad ;-) Joonas Liik <liik.joonas@gmail.com> - 2015-05-02 16:50 +0300
                Re: Python is not bad ;-) Joonas Liik <liik.joonas@gmail.com> - 2015-05-02 18:53 +0300
                Re: Python is not bad ;-) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 11:00 -0600
                Re: Python is not bad ;-) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 11:17 -0600
                Re: Python is not bad ;-) Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-05-02 18:22 +0100
              Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-02 12:29 +0200
            Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-02 11:33 +0200
              Re: Python is not bad ;-) Dave Angel <davea@davea.name> - 2015-05-02 06:35 -0400
                Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-05-02 13:12 +0200
              Re: Python is not bad ;-) Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-02 09:31 -0600
      Re: Python is not bad ;-) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-01 15:56 +1000
    Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 13:10 +0200
  Re: Python is not bad ;-) Michael Torrie <torriem@gmail.com> - 2015-04-30 08:03 -0600
    Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 18:11 +0200
      Re: Python is not bad ;-) Christian Gollwitzer <auriocus@gmx.de> - 2015-04-30 19:59 +0200
        Re: Python is not bad ;-) Cecil Westerhof <Cecil@decebal.nl> - 2015-04-30 22:05 +0200

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