Re: NDSolve with implicit function
- To: mathgroup at smc.vnet.net
- Subject: [mg65890] Re: NDSolve with implicit function
- From: "Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de>
- Date: Fri, 21 Apr 2006 01:33:26 -0400 (EDT)
- Organization: Uni Leipzig
- References: <e27k92$5ft$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
calcY[x_?NumericQ] :=
y /. FindRoot[Sin[x^2] + y - 1, {y, 1}][[1]]
sol = NDSolve[{x'[t] == Cos[x[t]*calcY[x[t]]],
x[0] == 0}, x[t], {t, 0, Pi}];
Plot[Evaluate[x[t] /. sol[[1]]], {t, 0, Pi}];
Regards
Jens
<rondeau at uvic.ca> schrieb im Newsbeitrag
news:e27k92$5ft$1 at smc.vnet.net...
|I am trying to numerically solve a differential
equation
| {x'[t]==f[x[t],y[t]], x[0]=a} , where y[t] is
the numerical solution to an
| implicit function g[x[t],y[t]]==0 (not a
polynomial).
|
| In other words, given x[t], we should be able to
numerically compute y[t]
| from the implicit function and it would enter
numerically into the function
| f of NDSolve.
|
| Anyone with an idea on how to do this?
|
| Thanks.
| Daniel
|