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Re: NDSolve error: "Cannot find starting value for the variable x"

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• Subject: [mg40493] Re: [mg40475] NDSolve error: "Cannot find starting value for the variable x"
• From: CAP F <Ferdinand.Cap at eunet.at>
• Date: Tue, 8 Apr 2003 03:02:55 -0400 (EDT)
• References: <b6m0dv$ehe$1@smc.vnet.net> <200304070855.EAA08000@smc.vnet.net>
• Sender: owner-wri-mathgroup at wolfram.com

[mg40475] NDSolve error
Dear Joseph,
For a boundary value problem only one single differential equation of n-th
order is supported by NDSolve, not a system of several equations. Try to use a
shooting method, see page 62 of my textbook:
"Mathematical Methods in Physics and Engineering with Mathematica, CRC Press,
2003,
ISBN 1584884029
Greetings F. Cap     Ferdinand.Cap at eunet.at

> I'm trying to use NDSolve to solve a coupled system of differential
> equations (total differential order of 5) with 5 given initial conditions.
> I've gotten the error "Cannot find starting value for the variable x", which
> I had thought one only got if the highest derivative of one of the initial
> conditions was higher than in the system of equations. However, my
> highest-order initial condition is only a first derivative, so I don't
> believe this is the case.
>
> Can anyone help me solve this?
>
> Thanks,
>
> Joe Jewell
> jjewell at caltech.edu
>
> NDSolve[{
>     f'''[x] + 3f[x]*f''[x] - 2(f'[x])^2 + T[x] == 0,
>     T''[x] + 3*1000*f[x]T'[x] == 0,
>     f[0] == f'[0] == 0,
>      T[0] == 1,
>     T[\[Infinity]] == 0,
>     f'[\[Infinity]] == 0
>     }, {f, T}, {x, 0, 10}]

• References:
  • NDSolve error: "Cannot find starting value for the variable x"
    • From: "Joseph S. Jewell" <jjewell@caltech.edu>