Re: Compression

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From	Peter Otten <__peter__@web.de>
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Subject	Re: Compression
Date	Thu, 14 Jul 2016 10:59:05 +0200
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Steven D'Aprano wrote:

> How about some really random data?
> 
> py> import string
> py> data = ''.join(random.choice(string.ascii_letters) for i in
> range(21000)) py> len(codecs.encode(data, 'bz2'))
> 15220
> 
> That's actually better than I expected: it's found some redundancy and
> saved about a quarter of the space. 

It didn't find any redundancy, it found the two unused bits:

>>> math.log(len(string.ascii_letters), 2)
5.700439718141093
>>> 21000./8*_
14963.654260120367

Thread

Compression Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2016-07-14 18:16 +1000
  Re: Compression wxjmfauth@gmail.com - 2016-07-14 01:52 -0700
  Re: Compression Peter Otten <__peter__@web.de> - 2016-07-14 10:59 +0200
  Re: Compression Chris Angelico <rosuav@gmail.com> - 2016-07-14 21:07 +1000

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