Re: NDSolve error message: Can't find starting value ...
- To: mathgroup at smc.vnet.net
- Subject: [mg23803] Re: [mg23755] NDSolve error message: Can't find starting value ...
- From: "Mark Harder" <harderm at ucs.orst.edu>
- Date: Sat, 10 Jun 2000 03:00:05 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Axel, >P.S. Btw., this is done with Mathematica 4. > Then, you should look in the Help browser under 'Other Information>Warning Messages>NDSolve>NDSolve::ndsv: ', where it says this message means that something is wrong with your initial/boundary conditions (but not much more) & gives 1 somewhat artificial example. Maybe someone more knowledgeable about ODEs than I can tell you what exactly is wrong. -mark harder -----Original Message----- From: Axel Kowald <axel at itb.biologie.hu-berlin.de> To: mathgroup at smc.vnet.net Subject: [mg23803] [mg23755] NDSolve error message: Can't find starting value ... >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 > > >