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Date:      Fri, 14 Sep 2012 21:37:31 +0200
From:      =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To:        Pawel Jakub Dawidek <pjd@FreeBSD.org>
Cc:        Arthur Mesh <arthurmesh@gmail.com>, Doug Barton <dougb@FreeBSD.org>, freebsd-rc@freebsd.org, obrien@freebsd.org, freebsd-security@freebsd.org, RW <rwmaillists@googlemail.com>, d@delphij.net
Subject:   Re: svn commit: r239569 - head/etc/rc.d
Message-ID:  <86vcfge6pw.fsf@ds4.des.no>
In-Reply-To: <20120914153030.GA2146@garage.freebsd.pl> (Pawel Jakub Dawidek's message of "Fri, 14 Sep 2012 17:30:30 %2B0200")
References:  <86sjao7q8c.fsf@ds4.des.no> <20120911205302.27484fd6@gumby.homeunix.com> <20120911200925.GA88456@dragon.NUXI.org> <504FA76A.5000209@delphij.net> <20120911211730.GB89188@dragon.NUXI.org> <504FAB87.3020701@delphij.net> <20120911215212.GA89515@dragon.NUXI.org> <504FBD15.8040907@delphij.net> <20120911224855.GE14077@x96.org> <504FC2BD.6070402@delphij.net> <20120914153030.GA2146@garage.freebsd.pl>

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Pawel Jakub Dawidek <pjd@FreeBSD.org> writes:
> Also, compression can definiately increase entropy per byte, but IMHO it
> can also lose some entropy overall. With lossless compression you don't
> lose data, but I don't believe you can say that you don't lose entropy.

By definition (both the definition of entropy in this context and the
definition of lossless data compression), the amount of entropy in the
output is exactly the same as in the input.  If the output is actually
smaller than the input (which is not necessarily the case, but is safe
to assume when the input is ascii text), then clearly the amount of
entropy per byte has increased.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no



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