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Re: Most pythonic way of rotating a circular list to a canonical point

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On Saturday, August 1, 2015 at 3:52:25 PM UTC-7, Lukas Barth wrote:
> On Saturday, August 1, 2015 at 11:37:48 PM UTC+2, Emile van Sebille wrote:
> > Well, it looks to me that I don't know what a 'canonical rotation' is -- 
> 
> That's because it is not defined. ;)
> 
> I need a way to rotate one of these lists in a way so that it will produce the same output every time, regardless of what the input rotation was.
> 
> Example:
> 
> [0,1,2,3,4] => [0,1,2,3,4]
> [2,3,4,0,1] => [0,1,2,3,4]
> [3,4,0,1,2] => [0,1,2,3,4]
> ...
> 
> It doesn't have to be "[0,1,2,3,4]", it can just as well be [2,3,4,1,0], as long as it's always the same.
> 
> Did that make it clearer?
> 

Is this "canoncal rotation" different than sorting. I think you mean it to be, but these examples all look like sorting to me.

I think the collections.deque object has a rotate method, and rotating through the possibilities looking for matches may work, or take any deque, rotate so the minimum value is at the first place in the deque, and then compare.

Or am I not understanding what you mean?

Josh

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Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 13:34 -0700
  Re: Most pythonic way of rotating a circular list to a canonical point Emile van Sebille <emile@fenx.com> - 2015-08-01 13:49 -0700
    Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 14:12 -0700
      Re: Most pythonic way of rotating a circular list to a canonical point Emile van Sebille <emile@fenx.com> - 2015-08-01 14:29 -0700
  Re: Most pythonic way of rotating a circular list to a canonical point Marko Rauhamaa <marko@pacujo.net> - 2015-08-01 23:57 +0300
    Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 14:04 -0700
      Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 16:32 -0700
      Re: Most pythonic way of rotating a circular list to a canonical point Marko Rauhamaa <marko@pacujo.net> - 2015-08-02 09:25 +0300
  Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 14:24 -0700
    Re: Most pythonic way of rotating a circular list to a canonical point Emile van Sebille <emile@fenx.com> - 2015-08-01 14:36 -0700
      Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 15:51 -0700
        Re: Most pythonic way of rotating a circular list to a canonical point Joel Goldstick <joel.goldstick@gmail.com> - 2015-08-01 18:58 -0400
        Re: Most pythonic way of rotating a circular list to a canonical point Josh English <Joshua.R.English@gmail.com> - 2015-08-01 16:43 -0700
        Re: Most pythonic way of rotating a circular list to a canonical point Steven D'Aprano <steve@pearwood.info> - 2015-08-02 18:17 +1000
    Re: Most pythonic way of rotating a circular list to a canonical point Paul Rubin <no.email@nospam.invalid> - 2015-08-01 14:43 -0700
      Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 15:53 -0700
        Re: Most pythonic way of rotating a circular list to a canonical point Paul Rubin <no.email@nospam.invalid> - 2015-08-01 19:47 -0700
          Re: Most pythonic way of rotating a circular list to a canonical point Paul Rubin <no.email@nospam.invalid> - 2015-08-01 20:02 -0700
    Re: Most pythonic way of rotating a circular list to a canonical point Cameron Simpson <cs@zip.com.au> - 2015-08-02 08:25 +1000
      Re: Most pythonic way of rotating a circular list to a canonical point Lukas Barth <mail@tinloaf.de> - 2015-08-01 15:55 -0700
        Re: Most pythonic way of rotating a circular list to a canonical point Cameron Simpson <cs@zip.com.au> - 2015-08-02 11:20 +1000
  Re: Most pythonic way of rotating a circular list to a canonical point wolfram.hinderer@googlemail.com - 2015-08-01 17:07 -0700
  Re: Most pythonic way of rotating a circular list to a canonical point pavlovevidence@gmail.com - 2015-08-02 03:51 -0700
  Re: Most pythonic way of rotating a circular list to a canonical point Tim Chase <python.list@tim.thechases.com> - 2015-08-02 13:19 -0500
  Re: Most pythonic way of rotating a circular list to a canonical point Larry Hudson <orgnut@yahoo.com> - 2015-08-02 13:01 -0700
    Re: Most pythonic way of rotating a circular list to a canonical point Joonas Liik <liik.joonas@gmail.com> - 2015-08-02 23:58 +0300
      Re: Most pythonic way of rotating a circular list to a canonical point Larry Hudson <orgnut@yahoo.com> - 2015-08-03 12:56 -0700
    Re: Most pythonic way of rotating a circular list to a canonical point Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-08-03 15:19 +0100

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