On Wed, Sep 5, 2012 at 11:07 AM, davide prandi <davide_pra...@hotmail.it> wrote: > Hi everyone, > I'm Davide Prandi, and I'm a student of Politecnico di Milano, electronic > engineering. My professor of "Numerical computation" (he's present in this > mailing list) asked me to develop a code that implements the "ode23s" > method, present in matlab but not in Octave. Ode23s solves differential > equations (like ode23, odepkg package), but is builted for "stiff" problems. > I have referred to "The matlab ode suite (Shampine, Reichelt)", pp. 6-7, > where Rosenbrock formula, a particular form of Runge-Kutta methods, is > mathematically explained. My code is based on these formulas. Well, the code > basically works, but there is some feature that must be fixed. In > particular: > 1) I use "dfxpdp.m" (optim package) for the Jacobian computing. It works, > but it accepts equations in F(Y,t) form, and all the ode solvers require > equations in form F(t,Y). There is a way to redefine F, swapping the > dependent/independent variable? At moment, I'm testing the code putting the > equations in F(Y,t) form. > 2) There is an optional input in the function's prototype: "options". It use > "odeset" to define some parameters, for example user can change the initial > integration step size. I've implemented some of these options, and certainly > there is some things to do/fix. > > I hope that my work can be useful. If all the problems are fixed, I think > that this code may be integrated in the "odepkg" package. > How can I share the code? I enclose .m file or I copy all the code in a > e-mail? > Of course, I'm not a experienced programmer (this is the first time that I > do a big project), I will accept all the advice. > Thanks to all, > > Davide > > ------------------------------------------------------------------------------ > Live Security Virtual Conference > Exclusive live event will cover all the ways today's security and > threat landscape has changed and how IT managers can respond. Discussions > will include endpoint security, mobile security and the latest in malware > threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ > _______________________________________________ > Octave-dev mailing list > Octave-dev@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/octave-dev >
Hi Davide You can share your code using the Feature Request forum http://sourceforge.net/tracker/?group_id=2888&atid=352888 Just upload your file (if you have more than one, compress them) and send an e-mail to this mailing list. Then the interested people will look at your code, send you comments on style and maybe even test it! Thank you for your collaboration. JPi -- M. Sc. Juan Pablo Carbajal ----- PhD Student University of Zürich http://ailab.ifi.uzh.ch/carbajal/ ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Octave-dev mailing list Octave-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/octave-dev
