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Re: memory
From: |
Martin Helm |
Subject: |
Re: memory |
Date: |
Tue, 5 Apr 2011 14:03:45 +0200 |
User-agent: |
KMail/1.13.6 (Linux/2.6.34.7-0.7-desktop; KDE/4.6.1; x86_64; ; ) |
Am Dienstag, 5. April 2011, 13:13:21 schrieb nuncio m:
> Hi martin,
> Here is the code snippet
> R=f' * f ---------------------------------(1)
> [C,L]=eigs(R);-----------------------(2)
> [C1,Lambda,CC]=svd(f);-------------(3)
>
> memory error is shown at 1
> thanks
> nuncio
>
> On Tue, Apr 5, 2011 at 4:26 PM, Martin Helm <address@hidden> wrote:
> > Am Dienstag, 5. April 2011, 11:06:09 schrieb nuncio m:
> > > Hi list,
> > >
> > > What is the maximum size of a matrix that octave can hold. Why I am
> > >
> > > asking this is, I am getting a memory when I try to find the eigen
> > > values of a matrix of 348 rows and 29898 columns. I am using a 32
> > > bit open
> >
> > suse
> >
> > > on pentium 4 processor having 2 GB of RAM and a swap of 4.6 GB. Any
> > > help would be greatly appreciated.
> > >
> > > nuncio
> >
> > Your matrix is fairly small around 80 MB memory consumption, so no
> > problem in
> > itself at all. The amount of memory you can use depends on your system
> > architecture. With 32 bit you can use up to 2GB for a matrix, with a 64
> > bit (linux) system you can have a matrix up to 16 GB, this limit does
> > not exist if
> > octave is built with 64 bit indexing enabled (but this is still
> > experimental I
> > think).
> >
> > You say you run out of memory calculating the eigen values of a nonsquare
> > matrix (?). can you show us a short code snippet how you do that? I am
> > not sure if I really understand.
> > Do you calculate something like eig(a'*a) or eig(a*a')? If yes you are
> > better
> > served with looking at the svd command instead of calculating a matrix
> > product.
R is a matrix with 29898^2 entries which is about 7 GB of memory!
What's wrong with simply using svd(f), you just need to square the singular
values.
- Re: memory, (continued)
- Re: memory, Martin Helm, 2011/04/05
- Re: memory, nuncio m, 2011/04/05
- Re: memory, Moo, 2011/04/05
- Re: memory, nuncio m, 2011/04/05
- Re: memory, Martin Helm, 2011/04/05
- Message not available
- Re: memory, Martin Helm, 2011/04/06
- Message not available
- Re: memory, Martin Helm, 2011/04/08
- Re: memory, nuncio m, 2011/04/09
- Re: memory, Martin Helm, 2011/04/09
- Re: memory, nuncio m, 2011/04/10
- Re: memory,
Martin Helm <=