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. Oberdorfstr. 68 CH-9100 Herisau Tel. +41 71 353 8585, Fax +41 71 353 8907 E-Mail:<mailto:dh at metrohm.com> Internet:<http://www.metrohm.com>