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Re: NDSolve

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  • Subject: [mg86146] Re: NDSolve
  • From: Jens-Peer Kuska <kuska at>
  • Date: Mon, 3 Mar 2008 04:41:38 -0500 (EST)
  • References: <fqet8u$jff$>


a) we are not clairvoyants and it is rather hard to imagine what
    you wish to do without an example
b) if there is a "sudden changes in the slope" the step size control
    will reduce the step size dramatical and monitoring the step size
    is a good indicator for a "sudden changes in the slope"
c) the case that "mean that Mathematica took the wrong root of a complex 
number" mean in many cases the the right hand side of your ODE's
   are not Lipshitz continuous and that there exist no solution
   at all


Alex Cloninger wrote:
> So I'm running an NDSolve operation on a series of coupled ODE's.  I want to look at specific results every 10 steps or so to see if I have any sudden changes in the slope of the graph (the sudden changes would mean that Mathematica took the wrong root of a complex number).  I'm not sure what I can do to get this information.
> If anyone could help me out, I'd be very appreciative.
> Thanks,
> Alex

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