A85: Re: Compression

To: <assembly-85@lists.ticalc.org>
Subject: A85: Re: Compression
From: "Dines Justesen" <dines@resnet.gatech.edu>
Date: Mon, 2 Nov 1998 10:05:46 -0500
Delivered-To: assembly-85-outgoing@towerguard.unix.edu.sollentuna.se
Reply-To: assembly-85@lists.ticalc.org


It is impossible to make a program which can compress any string to half its
size ! However a zip like program might be able to give some compression for
most program. Make a program which could compres string on the calc has been
suggested before (several times), but no one has ever made a useble one. The
reason is that programs are fairly "random", which means that simpel
routines does not give much compression. To get  good compression of
programs you need a fairly complex routine, which takes up more space than
it would save.

If you want to try to make a compression program, routines to create and
delete vars has been found in the ROM, and the addr of them in all ROM
versions has been posted to the list. (These functions might be included in
Usgard)


Dines
-----Original Message-----
From: Jason Warner <jgwarner@wesnet.com>
To: assembly-85 <assembly-85@towerguard.unix.edu.sollentuna.se>
Date: Monday, November 02, 1998 9:18 AM
Subject: A85: Compression


>
>Someone has probably already asked this question, but If they did I
>missed it. Anyway, I thought of a way to compress a string to half it's
>size and the only problem I know of are these:
>
>How would I erase the the string after it is compressed?
>How do I create a new string to uncompresss the compressed string?
>
>Can anyone help me with these? My idea may end up going down the drain
>but I have it would be cool.
>
>Jason Warner
>