Re: [Tutor] Dictionary, integer, compression

2009-04-29 Thread Alan Gauld 


Dinesh B Vadhia dineshbvad...@hotmail.com wrote

Say, you have a dictionary of integers, are the integers stored 
in a compressed integer format or as integers ie. are integers 
encoded before being stored in the dictionary and then 
decoded when read?


I can't think of any reason to compress them, I imagine they 
are stored as integers. But given the way Python handlers 
integers with arbitrarily long numbers etc it may well be more 
complex than a simple integer (ie 4 byte number). But any 
form of compression would be likely to hit performamce 
so I doubt that they would be compressed.


Is there anything that made you think they might be?

HTH


--
Alan Gauld
Author of the Learn to Program web site
http://www.alan-g.me.uk/

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Re: [Tutor] Dictionary, integer, compression

2009-04-29 Thread Stefan Behnel 
Dinesh B Vadhia wrote:
 Say, you have a dictionary of integers, are the integers stored in a
 compressed integer format or as integers ie. are integers encoded before
 being stored in the dictionary and then decoded when read?

Integer objects are not special cased in dictionaries. They are stored as
normal int/long objects.

Dictionaries do not use any kind of compression in Python.

Stefan

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Re: [Tutor] Dictionary, integer, compression

2009-04-29 Thread Dinesh B Vadhia 
Alan

I want to perform test runs on my local machine with very large numbers of 
integers stored in a dictionary.  As the Python dictionary is an built-in 
function I thought that for very large dictionaries there could be compression. 
 Done correctly, integer compression wouldn't affect performance but could 
enhance it.  Weird, I know!  I'll check in with the comp.lang.python lot.

Dinesh




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Date: Wed, 29 Apr 2009 17:35:53 +0100
From: Alan Gauld alan.ga...@btinternet.com
Subject: Re: [Tutor] Dictionary, integer, compression
To: tutor@python.org
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Dinesh B Vadhia dineshbvad...@hotmail.com wrote

 Say, you have a dictionary of integers, are the integers stored 
 in a compressed integer format or as integers ie. are integers 
 encoded before being stored in the dictionary and then 
 decoded when read?

I can't think of any reason to compress them, I imagine they 
are stored as integers. But given the way Python handlers 
integers with arbitrarily long numbers etc it may well be more 
complex than a simple integer (ie 4 byte number). But any 
form of compression would be likely to hit performamce 
so I doubt that they would be compressed.

Is there anything that made you think they might be?

HTH


-- 
Alan Gauld
Author of the Learn to Program web site
http://www.alan-g.me.uk/

 
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