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From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: ordinary differential equations
Date: Mon, 23 Jan 2012 08:09:35 -0800 (PST)
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On 23 Jan., 15:10, "Pag Max" <tismarkhanNOS...@gamil.com> wrote:
> I have a set of ode something like
>
> x={x1,x2}
>
> x1_dd=f(x2_dd)
> and
> x2_dd=g(x1_dd)
>
> While this can be solved using standard ode45 prodcedure such as
>
> dx(1)=x(2);
> dx(2)=f(dx(4))
> dx(3)=x(4);
> dx(4)=g(dx(2))
>
> I am not sure if it is right from numerical methods perspective because I have LHS of second equation in RHS of first and vice versa.
>
> Any thoughts on this would be appreciaetd.


Use ode15i for your system of 4 equations from above.

Best wishes
Torsten.