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Re: howto remove the thousand separator

References <201304150257331336590@gmail.com> <mailman.596.1365966380.3114.python-list@python.org> <516b49dc$0$29977$c3e8da3$5496439d@news.astraweb.com> <mailman.611.1365986675.3114.python-list@python.org> <516b5471$0$29977$c3e8da3$5496439d@news.astraweb.com>
Date 2013-04-15 11:29 +1000
Subject Re: howto remove the thousand separator
From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.612.1365989366.3114.python-list@python.org> (permalink)

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On Mon, Apr 15, 2013 at 11:14 AM, Steven D'Aprano
<steve+comp.lang.python@pearwood.info> wrote:
> On Sun, 14 Apr 2013 17:44:28 -0700, Mark Janssen wrote:
>> What on earth makes you think that is an O(n**2) algorithm and not O(n)?
>
> Python *might* optimize the first concatenation, '' + 'fe', to just reuse
> 'fe', (but it might not). Let's assume it does, so that no copying is
> needed. Then it gets to the second concatenation, and now it has to copy
> characters, because strings are immutable and cannot be modified in
> place.

There are actually a lot of optimizations done, so it might turn out
to be O(n) in practice. But strictly in the Python code, yes, this is
definitely O(n*n).

ChrisA

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Re: howto remove the thousand separator Mark Janssen <dreamingforward@gmail.com> - 2013-04-14 12:06 -0700
  Re: howto remove the thousand separator Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-15 00:29 +0000
    Re: howto remove the thousand separator Mark Janssen <dreamingforward@gmail.com> - 2013-04-14 17:44 -0700
      Re: howto remove the thousand separator Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-15 01:14 +0000
        Re: howto remove the thousand separator Chris Angelico <rosuav@gmail.com> - 2013-04-15 11:29 +1000
          Re: howto remove the thousand separator Walter Hurry <walterhurry@lavabit.com> - 2013-04-15 02:25 +0000
            Re: howto remove the thousand separator Roy Smith <roy@panix.com> - 2013-04-14 22:35 -0400
              Re: howto remove the thousand separator Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-15 07:04 +0000
        Re: howto remove the thousand separator Rotwang <sg552@hotmail.co.uk> - 2013-04-15 03:19 +0100
          Re: howto remove the thousand separator Ned Deily <nad@acm.org> - 2013-04-14 22:15 -0700
          Re: howto remove the thousand separator Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-04-15 07:03 +0000
            Re: howto remove the thousand separator Chris Angelico <rosuav@gmail.com> - 2013-04-15 17:39 +1000
            Re: howto remove the thousand separator Rotwang <sg552@hotmail.co.uk> - 2013-04-15 23:16 +0100

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