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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Larger matrices
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Date: Thu, 7 Aug 2008 09:44:25 +0200
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Date: 2008-08-07T09:44:25+02:00
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On Wed, 6 Aug 2008 11:40:09 -0700 (PDT), amado.alves@gmail.com wrote:

>> IMO, for such huge matrices and vectors, it is better to use in-place
>> operations, rather than a loose functional programming style.
> 
> You mean a procedure with out parameter instead of function?

in out. For example:

procedure Multiply
   (Accumulator : in out Real_Matrix; Multiplicand : Real_Matrix);

> Is there such utility?

You mean in the standard library. Unfortunately no, which limits its
usability. But you could implement them, as well as frequent mixed cases
like:

   A := A * B + C

>> And do you have dense 5000 x 5000 matrices? You are a hardworking man!
> 
> It's an hypertext.

An incidence matrix? I believe there exist special methods for
representation and handling them. But sorry, my numerical methods is quite
outdated.

> So now I want to increase the stack size. To 200M.

Ooch, that is a bad, bad idea. Stack is not for that. It should take no
longer than 5 min to implement Multiply in order that it would use O(n) of
pool instead of O(n**2) of stack...

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de