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Re: Precision
From: |
Diego Ruiz |
Subject: |
Re: Precision |
Date: |
Tue, 16 Nov 2004 10:57:21 +0800 |
Thakns for your answer.
I'm facing the following problem:
A is an M-dimensional matrix (M^S x M^S x M). Just consider the
case of M=3 and S=5, we have a matrix with 177147 cells, with
double precision this means we need around 3MB of free memory or
storage space. If we let M=4 that number becomes overwhelming.
With single precision this requirement is importantly reduced.
Actually lots of cells in A are zero. That was the reason for
which I wanted to work with SPARSE matrices. But when trying to
install Octave Forge in my Fedora Core 2 OS I faced several
problems (you can check the discussion held some days ago on the
topic).
I've not expertise in Unix/Linux operative systems and solving
those problems turns out to be quite challenging. That's the
reason for which considered the idea of using single precision.
Do you have a better idea?
Thank you,
Diego Ruiz
******************************************************
Diego Ruiz Hernández
www.econ.upf.es/~diruiz
Universitat Pompeu Fabra, Dept. d'Economia i Empresa
c/ Ramon Trias Fargas 25-27, 08025,
Barcelona, ESPAÑA
Fall Term:
Edinburgh University, School Of Management
William Robertson Building, 50 George Square
Edinburgh EH8 9JY, UK
******************************************************
---------- Original Message -----------
From: "John W. Eaton" <address@hidden>
To: "Diego Ruiz" <address@hidden>
Sent: Mon, 15 Nov 2004 16:19:38 -0500
Subject: Precision
> On 15-Nov-2004, Diego Ruiz <address@hidden> wrote:
>
> | After several failed attempts... I've abandoned my
> idea of | working with Sparse matrices... but I keep
> loyal to Octave.
>
> I think that sparse matrices will be a part of the core Octave
> distribution relatively soon.
>
> | Now my question is, how can I change the precision of
> a Matrix? | I mean, if function "funfun" returns matrix
> A, is there any | comand equivalent to Matlab's
> "single(A)" for converting matrix | A to single
> precision within the function and then, when | necessary
> expand it again with "double(A)" for performing | operations?
>
> Not yet, no.
>
> Why do you need single precision?
>
> jwe
------- End of Original Message -------
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-------------------------------------------------------------
- Precision, Diego Ruiz, 2004/11/15
- Precision, John W. Eaton, 2004/11/15
- Re: Precision,
Diego Ruiz <=