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Date: Mon, 4 Nov 2013 07:08:03 -0600
From: Tim Chase <python.list@tim.thechases.com>
To: python-list@python.org
Subject: Re: Algorithm that makes maximum compression of completly diffused data.
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Xref: csiph.com comp.lang.python:58442

On 2013-11-03 19:40, Mark Janssen wrote:
> But you cheated by using a piece of information from "outside the
> system": length.  A generic compression algorithm doesn't have this
> information beforehand.

By cheating with outside information, you can perfectly compress any
one data-set down to 1 bit.  Just store the data in the program, then
store 1 bit of "is this file the data we have stored in the
program?".  Granted, in modern OSes, you waste 7 extra bits since
they require you to write an entire byte at a time. :-)

And with that, you could even have an empty file and test for a file
extension. ;-)

-tkc