Re: [OctDev] Ode23s

[Olaf T. <i7...@t-...>]

On Wed, Sep 05, 2012 at 03:11:37PM +0200, davide prandi wrote:
> 
> Thanks to everyone.I had already tried to change the variable's
> order with '@', but the method solves a SYSTEM of differential
> equations. I give you an example:
> [T,Y]=ode23s(@fun, [0 5], [1 2 3]);
> where 'fun' is a vector of equations:
> function Fv=fun(Y,t)Fv(1,1)=2*Y(1)+Y(2)+5*Y(3)+exp(-2*t);Fv(2,1)=-3*Y(1)-2*Y(2)-8*Y(3)+2*exp(-2*t)-cos(3*t);Fv(3,1)=3*Y(1)+3*Y(2)+2*Y(3)+cos(3*t);
> 
> The problem is: all of ode solvers take in input function in
> fun(t,Y) form. dfxpdp computes jacobian matrix with function in
> fun(Y,t) form.Obviously fun(t,Y) is user-defined, and I've to find a
> way to convert fun(t,Y) in fun(Y,t) form. When this problem is
> fixed, I can upload the .m file.  Thanks, Davide

I thought my previous post would show you how to solve just this
problem. It does not matter whether your method solves a system of
equations as above or only one.

Olaf

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