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Topic: [Q] solving ODE with rk45, gear,...
Replies: 0

 Wojtek Swiatek Posts: 3 Registered: 12/7/04
[Q] solving ODE with rk45, gear,...
Posted: Oct 1, 1996 3:17 PM

Hello,

I am trying to solve a rather complex set of ODE and as to now I
managed to do something with ode23 and ode45. Both give results
which are acceptable but I also would like to check the GEAR
method.
There is a gear algoritm implemented (gear) and everything would
be fine if I knew how to write my set of ODEs so that it is
understood by gear (or rk45). I saw the example function but
truly speaking I didn't understand it at all :-}

I would be grateful if someone could write me how to code the
following set of ODE (in the form of the parameter SYSTEM) so
that it can be understood by those functions.

Let A = A(t), B = B(t)
dA/dt = A - B
dB/dt = A * B

Thank you for replaying by email - I have a poor news feedback
and do not want to miss any solution/pointer. I will summarise
if there is any interest.

Best Regards,
Wojtek
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| Wojtek Swiatek, AGH, Dept. of High-Energy Physics, Krakow, Poland |
| CERN, Geneva, Switzerland DESY, Hamburg, DE |
| swiatek@ftj.agh.edu.pl |
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