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Re: numerical solution of an ODE doesn't make sense


On Jul 22, 2004, at 2:46 AM, Ita wrote:

> Hello, and thanks in advance to any response.
> I solved a 2nd degree ode with NDSolve for the unknown x(t) for 2 time
> domains: 0<t<100 and 0<t<700, with the same boundary conditions.
> than I ploted the two solutions for 0<t<20, and they came out 
> different ! it
> is like the solution in t<20 is influenced by the solution in t>100 - 
> it
> doesn't make sense.
> thanks,
> Itamar.
>

Most likely it's because of different step sizes. Use the MaxStepSize 
or MaxStepFraction option; e.g., MaxStepSize->1 or 
MaxStepFraction->1/100.

-----
Selwyn Hollis
http://www.appliedsymbols.com
(edit reply-to to reply)


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