From owner-metabolic-reg@net.bio.net Thu Oct 07 06:54:00 1999 Path: biosci!newshost.lanl.gov!logbridge.uoregon.edu!newsfeed.icl.net!newsfeed.icl.net!dispose.news.demon.net!demon!news.demon.co.uk!demon!fssc.demon.co.uk!not-for-mail From: "Herbert M Sauro" Newsgroups: bionet.metabolic-reg Subject: Re: how do I define the l mtarix from MCA in maple? Date: Wed, 6 Oct 1999 21:34:19 +0100 Message-ID: <939282413.1420.0.nnrp-12.c2de3927@news.demon.co.uk> References: <939143188.8182.0.nnrp-02.c2de3927@news.demon.co.uk> NNTP-Posting-Host: fssc.demon.co.uk X-NNTP-Posting-Host: fssc.demon.co.uk:194.222.57.39 X-Trace: news.demon.co.uk 939282413 nnrp-12:1420 NO-IDENT fssc.demon.co.uk:194.222.57.39 X-Complaints-To: abuse@demon.net X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.00.2014.211 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2014.211 Lines: 39 What I meant by a 'nice looking' L matrix was one which was partitioned vertically into an Identity matrix and the L0 matrix, that is all, but I know what you mean by sensible conservation relations. Computationally I guess it makes not difference except as you suggest it is prefereable from a human perspective to have positive conservation relations if possible. One advantage of a the L matrix is that it is partitioned into {I | L0]^t which is a standard form. Herbert PS SVD, sorry for the jargon, Single Value Decomposition! "Jannie Hofmeyr" wrote in message news:E11Yq7u-000867-02@mail.sun.ac.za... > Herbert Sauro wrote in response to my > > > > What about Stefan Schuster's > > > algorithm? - being based on convex algebra it has the nice property of > > > providing 'sensible' conservation equations. > > > But I presume if you did this you wouldn't get a 'nice looking' L matrix > > (but an L matrix nevertheless)? And are are any consequences down the > > algebra line when one comes to compute the coefficients (I'm not sure)? > > I am not sure what you mean by a 'nice-looking' L matrix, Herbert. By a > sensible conservation equation I mean one that refers to the different forms > of a single chemical moiety, i.e. with positive coefficients (). The row in the L- > matrix would then just have negative coefficients. > > Jannie > > Prof. Jannie Hofmeyr Tel: +27 21 808 3039 .