Re: save dictionary to a file without brackets.

From	Andrew Cooper <amc96@cam.ac.uk>
Newsgroups	comp.lang.python
Subject	Re: save dictionary to a file without brackets.
References	(1 earlier) <F1B463BB-19A6-4DB1-99B3-929CCBFB5920@gmail.com> <50241F14.2060209@tim.thechases.com> <36EA3847-6713-4C12-B47B-9B5E10325F00@gmail.com> <502429C3.5000600@tim.thechases.com> <mailman.3120.1344548050.4697.python-list@python.org>
Message-ID	<MsWUr.1183213$%k.489563@fx20.am4> (permalink)
Organization	virginmedia.com
Date	2012-08-09 23:03 +0100

Show all headers | View raw

On 09/08/2012 22:34, Roman Vashkevich wrote:
> Actually, they are different.
> Put a dict.{iter}items() in an O(k^N) algorithm and make it a hundred thousand entries, and you will feel the difference.
> Dict uses hashing to get a value from the dict and this is why it's O(1).
> 

Sligtly off topic, but looking up a value in a dictionary is actually
O(n) for all other entries in the dict which suffer a hash collision
with the searched entry.

True, a sensible choice of hash function will reduce n to 1 in common
cases, but it becomes an important consideration for larger datasets.

~Andrew

Thread

save dictionary to a file without brackets. giuseppe.amatulli@gmail.com - 2012-08-09 13:11 -0700
  Re: save dictionary to a file without brackets. Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 00:22 +0400
  Re: save dictionary to a file without brackets. Tim Chase <python.list@tim.thechases.com> - 2012-08-09 15:35 -0500
  Re: save dictionary to a file without brackets. Giuseppe Amatulli <giuseppe.amatulli@gmail.com> - 2012-08-09 15:35 -0500
  Re: save dictionary to a file without brackets. Gelonida N <gelonida@gmail.com> - 2012-08-09 22:35 +0200
  Re: save dictionary to a file without brackets. Giuseppe Amatulli <giuseppe.amatulli@gmail.com> - 2012-08-09 15:38 -0500
  Re: save dictionary to a file without brackets. Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 00:41 +0400
  Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-09 22:17 +0100
  Re: save dictionary to a file without brackets. Tim Chase <python.list@tim.thechases.com> - 2012-08-09 16:21 -0500
  Re: save dictionary to a file without brackets. Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 01:34 +0400
    Re: save dictionary to a file without brackets. Andrew Cooper <amc96@cam.ac.uk> - 2012-08-09 23:03 +0100
      Re: save dictionary to a file without brackets. Dave Angel <d@davea.name> - 2012-08-09 18:26 -0400
        Re: save dictionary to a file without brackets. Andrew Cooper <amc96@cam.ac.uk> - 2012-08-09 23:54 +0100
          Re: save dictionary to a file without brackets. Roy Smith <roy@panix.com> - 2012-08-09 19:05 -0400
            Re: save dictionary to a file without brackets. Chris Angelico <rosuav@gmail.com> - 2012-08-10 09:14 +1000
              Re: save dictionary to a file without brackets. Roy Smith <roy@panix.com> - 2012-08-09 19:24 -0400
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-10 00:33 +0100
                Re: save dictionary to a file without brackets. Tim Chase <python.list@tim.thechases.com> - 2012-08-09 19:16 -0500
                Re: save dictionary to a file without brackets. Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-10 08:54 +0000
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-10 10:37 +0100
                Re: save dictionary to a file without brackets. Roy Smith <roy@panix.com> - 2012-08-10 08:29 -0400
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-10 15:47 +0100
                Re: save dictionary to a file without brackets. alex23 <wuwei23@gmail.com> - 2012-08-12 17:15 -0700
                Re: save dictionary to a file without brackets. Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-13 08:05 +0000
                Re: save dictionary to a file without brackets. alex23 <wuwei23@gmail.com> - 2012-08-13 09:16 -0700
                Re: save dictionary to a file without brackets. rusi <rustompmody@gmail.com> - 2012-08-13 08:55 -0700
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-13 13:37 +0100
                Re: save dictionary to a file without brackets. alex23 <wuwei23@gmail.com> - 2012-08-13 09:14 -0700
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-13 18:07 +0100
                Re: save dictionary to a file without brackets. Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-14 02:54 +0000
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-14 12:33 +0100
                Re: save dictionary to a file without brackets. Alister <alister.ware@ntlworld.com> - 2012-08-14 15:05 +0000
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-14 19:15 +0100
                Re: save dictionary to a file without brackets. Mark Lawrence <breamoreboy@yahoo.co.uk> - 2012-08-13 18:43 +0100
                Re: save dictionary to a file without brackets. alex23 <wuwei23@gmail.com> - 2012-08-13 18:32 -0700
                Re: save dictionary to a file without brackets. Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-08-10 12:34 -0400
                Re: save dictionary to a file without brackets. Dave Angel <d@davea.name> - 2012-08-09 20:27 -0400
                Re: save dictionary to a file without brackets. Chris Angelico <rosuav@gmail.com> - 2012-08-10 10:31 +1000
          Re: save dictionary to a file without brackets. Dave Angel <d@davea.name> - 2012-08-09 19:38 -0400
      Re: save dictionary to a file without brackets. Tim Chase <python.list@tim.thechases.com> - 2012-08-09 17:39 -0500
      Re: save dictionary to a file without brackets. Chris Kaynor <ckaynor@zindagigames.com> - 2012-08-09 15:37 -0700
      Re: save dictionary to a file without brackets. Chris Angelico <rosuav@gmail.com> - 2012-08-10 08:53 +1000
        Re: save dictionary to a file without brackets. Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-11 11:26 +0000
          Re: save dictionary to a file without brackets. 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-12 04:59 -0700
      Re: save dictionary to a file without brackets. Chris Angelico <rosuav@gmail.com> - 2012-08-10 09:01 +1000
      Re: save dictionary to a file without brackets. Dave Angel <d@davea.name> - 2012-08-09 19:42 -0400
      Re: save dictionary to a file without brackets. 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-09 22:35 -0700
  Re: save dictionary to a file without brackets. Terry Reedy <tjreedy@udel.edu> - 2012-08-09 17:46 -0400
  Re: save dictionary to a file without brackets. Dave Angel <d@davea.name> - 2012-08-09 17:47 -0400
    Re: save dictionary to a file without brackets. 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-10 10:46 -0700
    Re: save dictionary to a file without brackets. 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-10 10:46 -0700
  Re: save dictionary to a file without brackets. Chris Kaynor <ckaynor@zindagigames.com> - 2012-08-09 14:49 -0700
  Re: save dictionary to a file without brackets. Chris Kaynor <ckaynor@zindagigames.com> - 2012-08-09 14:51 -0700
  Re: save dictionary to a file without brackets. Giuseppe Amatulli <giuseppe.amatulli@gmail.com> - 2012-08-09 16:53 -0500
  Re: save dictionary to a file without brackets. Roman Vashkevich <vashkevichrb@gmail.com> - 2012-08-10 02:02 +0400

csiph-web