From: Geert Fannes <Geert.Fannes@...>
Date: 2006-03-11T05:18:04+09:00
Subject: Re: how to introduce reference objects into ruby

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The columns store the actual values (doubles), and the rows store =
pointers to the corresponding doubles. This way, I can update a double =
directly via the columns, via the rows after dereferencing the pointers.

(The real truth is a bit more complex since pointers on a 64 bit machine =
take 64 bit, which wastes too much memory space. I store float and =
unsigned int indices instead of pointers, but the principle is the same)

Greetings,
Geert.


-----Original Message-----
From: Jim Weirich [mailto:jim@weirichhouse.org]
Sent: Fri 3/10/2006 8:23 PM
To: ruby-core@ruby-lang.org
Subject: Re: how to introduce reference objects into ruby
=20
Geert Fannes wrote:
[... example code elided ...]
> Unfortunately, this code duplicates the content values of the matrix, =
it
> has a copy inside the @columns and one inside the @rows and these need
> to be maintained so they stay the same, which is programming and
> execution overhead.

What does your C/C++ program do to get around this difficulty?

--=20
-- Jim Weirich       jweirich@one.net      http://onestepback.org
-----------------------------------------------------------------
"Beware of bugs in the above code; I have only proved it correct,
not tried it." -- Donald Knuth (in a memo to Peter van Emde Boas)



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