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From: Rich Freeman <rich0@gentoo.org>
To: gentoo-user@lists.gentoo.org
Subject: Re: [gentoo-user] Re: OT Best way to compress files with digits
Date: Fri, 31 Oct 2014 18:22:44 -0400	[thread overview]
Message-ID: <CAGfcS_k=HiWYZv7Uvn4A88J6NUGLd7q72yt5Jzis8wWeGBRpmg@mail.gmail.com> (raw)
In-Reply-To: <m30r7s$ee5$1@ger.gmane.org>

On Fri, Oct 31, 2014 at 4:25 PM, Grant Edwards
<grant.b.edwards@gmail.com> wrote:
>
> You're cheating.  The algorithm you tested will compress strings of
> arbitrary 8-bit values.  The algorithm you proposed will only compress
> strings of bytes where each byte can have only one of 10 values.
>

Of course.  I wasn't expecting the general-purpose algorithm to do as
well.  In some sense, part of the information that is being encoded is
actually in the compression algorithm itself (the mapping), while in a
general-purpose compression algorithm that information has to be part
of the compressed data stream.

I was just expecting gzip/etc to get much closer to the theoretical
limit.  I figured that it might be a few percent higher, but I wasn't
expecting a 10+% difference.

--
Rich


  reply	other threads:[~2014-10-31 22:22 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-10-31 15:36 [gentoo-user] OT Best way to compress files with digits meino.cramer
2014-10-31 15:45 ` Ralf
2014-10-31 15:59   ` meino.cramer
2014-10-31 16:52     ` Helmut Jarausch
2014-10-31 17:56     ` Rich Freeman
2014-10-31 18:55       ` David Haller
2014-10-31 19:23         ` Rich Freeman
2014-10-31 20:25           ` [gentoo-user] " Grant Edwards
2014-10-31 22:22             ` Rich Freeman [this message]
2014-11-01 17:15 ` James
2014-11-01 17:26   ` Alan McKinnon
2014-11-01 20:18     ` Matti Nykyri
2014-11-01 17:59   ` meino.cramer
2014-11-01 20:47     ` Alan McKinnon
2014-11-01 21:56       ` David W Noon
2014-11-02 12:06         ` Matti Nykyri
2014-11-03 15:48           ` Grant Edwards
2014-11-02 19:55         ` Alan McKinnon
2014-11-02 22:03           ` Peter Humphrey
2014-11-03 19:37             ` Mick
2014-11-04  2:04               ` Peter Humphrey
2014-11-04  6:35                 ` Mick

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