Re: [OctDev] Ode23s

[Martin H. <ma...@mh...>]

Am 05.09.2012 15:11, schrieb davide prandi:
> 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
>
Just attach your m file, your problem is most probably easy to solve
when seeing the code, most likely you have to change a single function
call as Olaf Till showed you.