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Re: Help with ODE's


Sam Halliday writes:
 > Hello there,
 >  i think gsl is a fantastic project, and i've been using it in my
 > simulations since i found out about it.
 >  i have only ever had to solve 2 ODEs at one time, and i was lucky
 > enough that the example in the documentation deals with this
 > scenario, however i find the API of the ODE part of the library to
 > be somewhat cryptic and i am having problems changing my code to
 > solve for 3 ODEs at one time.. could anyone please give me some
 > pointers as to how i would do that?

Check each function call in the program against the manual to see
where you need to change 'dimension' arguments from 2 to 3.

 >  and also, i noticed that to do an 8th order runge-kutta i must
 > declare a jacobian, could somebody please explain to me how i get
 > this from my equations? i am aware of jacobians in mathematics, but
 > never heard of it in numerics, i must admit i am of an analytic
 > background.

The jacobian isn't needed for Runge-Kutta, you can just use an empty
function.

regards
Brian Gough


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