public inbox for gsl-discuss@sourceware.org
 help / color / mirror / Atom feed
From: Emmanuel Benazera <ebenazer@email.arc.nasa.gov>
To: Brian Gough <bjg@network-theory.co.uk>
Cc: Emmanuel Benazera <ebenazer@email.arc.nasa.gov>,
	gsl-discuss@sources.redhat.com
Subject: Re: multivariate gaussian distribution (Code)
Date: Mon, 29 Dec 2003 16:47:00 -0000	[thread overview]
Message-ID: <20031229161748.GA5259@wow.arc.nasa.gov> (raw)
In-Reply-To: <16368.4822.391415.710874@debian.local>

Hi Brian,

I remember reading that the matrix decomposition through
eigensystems was more 'stable', while Cholesky was
probably faster. See the implementation in R:
http://rweb.stat.umn.edu/R/library/MASS/html/mvrnorm.html

I used the LU for determinant and matrix inverse only.
I'm not an expert in this field though...

Emmanuel

P.S.: in my opinion the multivariate_gaussian_pdf_LU is rather
useless, because for repeated calls, you want the inverse
 to be computed once and for all.

On Mon, Dec 29, 2003 at 11:41:10AM +0000, Brian Gough wrote:
> Emmanuel Benazera writes:
>  > Hi,
>  > 
>  > here is a tarball. Hope it helps.
>  > 
> 
> Is there any advantage of LU over Cholesky decomposition?
> 
> -- 
> Brian Gough
> 
> Network Theory Ltd
> 15 Royal Park
> Bristol BS8 3AL
> United Kingdom
> 
> Tel: +44 (0)117 3179309
> Fax: +44 (0)117 9048108
> Web: http://www.network-theory.co.uk/

  reply	other threads:[~2003-12-29 16:47 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-12-20 11:10 multivariate gaussian distribution Emmanuel Benazera
2003-12-22 14:21 ` Brian Gough
2003-12-28 10:29   ` multivariate gaussian distribution (Code) Emmanuel Benazera
2003-12-29 11:41     ` Brian Gough
2003-12-29 16:47       ` Emmanuel Benazera [this message]
2004-04-28  8:08       ` multivariate gaussian distribution (Code) / bugfix Emmanuel Benazera
2003-12-29 10:41 multivariate gaussian distribution (Code) Przemyslaw Sliwa
2003-12-29 11:52 Przemyslaw Sliwa
2003-12-29 17:54 Emmanuel Benazera
2003-12-29 23:02 Przemyslaw Sliwa
2003-12-30  9:47 Emmanuel Benazera
2003-12-30 10:55 ` Przemyslaw Sliwa
2003-12-30 11:31 ` Przemyslaw Sliwa

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20031229161748.GA5259@wow.arc.nasa.gov \
    --to=ebenazer@email.arc.nasa.gov \
    --cc=bjg@network-theory.co.uk \
    --cc=gsl-discuss@sources.redhat.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).