Re: Partial Differential Equations
- To: mathgroup at smc.vnet.net
- Subject: [mg92872] Re: Partial Differential Equations
- From: dh <dh at metrohm.ch>
- Date: Thu, 16 Oct 2008 05:05:33 -0400 (EDT)
- References: <gd4dm4$bh7$1@smc.vnet.net>
Hi Sergio,
you need enough boundary conditions to ensure that your problem has a
unique answer. E.g. ypu may request that the string is fixed at bouth
ends. Then you can set up the equations like:
eq={
D[u[x,t],{t,2}] == D[u[x,t],{x,2}] ,
u[x,0]== Sin[x],
Derivative[0,1][u][x,0]==0,
u[0,t]==0,
u[Pi,t]==0
};
sol=u/.NDSolve[eq,u,{x,0,Pi},{t,0,10}][[1]]
Plot3D[sol[x,t],{x,0,Pi},{t,0,10}]
hope this helps, Daniel
Sergio Miguel Terrazas Porras wrote:
> Hello Group:
>
>
>
> Hill someone please post an example for solving with Mathematica v. 6 a
> partial differential equation with boundary conditions ?
>
>
>
> Say, the one dimensional wave equation for a string with fixed ends and
> initial condition u(x,0) = f(x) and initial velocity u'(x,0) = 0.
>
>
>
> The documentation exemplifies only the general solution. When I try to
> include the boundary and initial conditions it does not solve it.
>
>
>
> Thanks in advance.
>
>
>
> Dr. Sergio Terrazas
>
> University of Juarez
>
> Chihuahua, Mexico
>
>
>
--
Daniel Huber
Metrohm Ltd.
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