Re: NDSolve of partial differentiel equation
- To: mathgroup at smc.vnet.net
- Subject: [mg18696] Re: NDSolve of partial differentiel equation
- From: Don Paddleford <don-paddleford at worldnet.att.net>
- Date: Thu, 15 Jul 1999 01:46:11 -0400
- Organization: AT&T WorldNet Services
- References: <7lul3m$lar@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Christian Damgaard wrote:
>
> Dear All,
>
> I am trying to solve a set of partial differential equation with three
> variables nummerically. However, as far as I see Mathematica only allows two
> variables in NDSolve. Is that correct ?
>
> The equations look like: px[x,y,t]==expr, py[x,y,t]==expr
>
> with boundary conditions: px[a,y,t]==0, px[b,y,t]==0,py[x,c,t]==0,
> py[x,d,t]==0
>
> and initial conditions: px[x,y,0]==expr,py[x,y,0]==expr
>
> If have tried something like:
>
> NDSolve[ {px[x,y,t]==expr, py[x,y,t]==expr, px[a,y,t]==0,
> px[b,y,t]==0,py[x,c,t]==0, py[x,d,t]==0,
> px[x,y,0]==expr,py[x,y,0]==expr},{px[x,y,t],py[x,y,t]},{x,x0,x1},{y,y0,y1},{
> t,t0,t1}]
>
> but it replyes that there are to many variables.
> replacing {x,x0,x1},{y,y0,y1},{t,t0,t1} with {{x,x0,x1},{y,y0,y1},{t,t0,t1}}
> does not work either.
>
> Christian Damgaard
> cfd at dmu.dk
Christian,
I raised this question to Wolfram a while back and was told NDSolve
would handle two variable PDE's at most.