Re: NDSolve error message: Can't find starting value ...
- To: mathgroup at smc.vnet.net
- Subject: [mg23776] Re: NDSolve error message: Can't find starting value ...
- From: Roland Franzius <Roland.Franzius at uos.de>
- Date: Sat, 10 Jun 2000 02:59:22 -0400 (EDT)
- References: <8hfggl$i4h@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Boundary values must be given for lower deriviatives than the highest.
Perhaps you mean R'[3]==R'[-3]==0 or R[3]==R[-3]==0?
Axel Kowald wrote:
>
> Hello,
>
> I try to solve the following second order ODE with NDSolve
>
> NDSolve[{0 == R''[x] + DiracDelta[x] - R[x], R''[-3] == 0,
> R''[3] == 0}, R, {x, -3, 3}]
>
> and I get the following error message:
>
> NDSolve::"ndsv": "Cannot find starting value for the variable x."
>
> I couldn't find any description of this message in the Mathematica book, so I'm
> not sure what to do. I have a second order ODE with two boundary
> conditions, what's missing ?
>
> Many thanks,
>
> Axel Kowald
>
> P.S. Btw., this is done with Mathematica 4.
--
Dr. Roland Franzius
Theor. Physik FB Physik, Univ. Osnabrueck
tel ++49 +541 969 2683 fax ++49 +451 969 2670
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