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Help with EJS ode solver
Ryan Healy
2 Posts

Hello!

I am looking for some advice regarding using the built-in ode solver in EJS.

I am attempting to simulate cold matter interacting with light. My simulation is producing results which are of a good approximation for a small number of atoms (n=3 for example) however when I increase the value to n=15 for example the ode solver breaks down and does not produce any results.

I am just wondering if there is a limit to the complexity of the equations for which EJS can handle.

Best regards,
Ryan


Replies to Help with EJS ode solver

Re: Help with EJS ode solver -
Wolfgang
146 Posts

Ryan--  There is no inherent limit, other than memory and processor speed, on the complexity or number of ODE equations that EJS can solve. The rate functions must, of course, be without discontinuities.  I have solved systems with a few hundred ODEs without difficulty.  See the Fermi Pasta Ulm model and the falling chain model.

http://www.compadre.org/osp/items/detail.cfm?ID=6891

http://www.compadre.org/osp/items/detail.cfm?ID=11056

Note how the preliminary code page in the falling chain model uses a linear algebra package to first solve for the rate equations.  --  Wolfgang



Re: Re: Help with EJS ode solver -
Ryan Healy
2 Posts

Hi Prof. Wolfgang,

Thanks for clearing that up, my problem must lie elsewhere.

Best regards,
Ryan



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