Re: Re: finite differencing of a PDE system
- To: mathgroup at smc.vnet.net
- Subject: [mg67748] Re: [mg67656] Re: finite differencing of a PDE system
- From: "Chris Chiasson" <chris at chiasson.name>
- Date: Thu, 6 Jul 2006 06:53:21 -0400 (EDT)
- References: <e8888u$92q$1@smc.vnet.net> <200607031038.GAA16538@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
First, thank you to my previous responders: Gregor Oliver Ruebenkoenig I changed my discretization of the interior PDEs so that they detect when they're on the boundary and appropriately change from center difference to forward or backward difference. current situation: CoefficientArrays creates a 155001x155001 (m) matrix and a 155001x1 (-b) matrix if I just feed it the finite difference equations generated from the interior PDEs. CoefficientArrays creates a 163779x155001 (m) matrix and a 163779x1 (-b) matrix if I feed it the interior and boundary conditions. LinearSolve[m,b] only works for a square m. questions: How do I include the Dirichlet boundary conditions for the stress? poor solutions: I could try LinearSolve with the homogeneous equations, but I have a feeling the m matrix will be singular or that there will otherwise be no solution. It certainly wouldn't be a solution corresponding to my boundary conditions. I could also try a least-squares fit (pseudo-inverse). That seems like it should be unnecessary. Thanks again for any input you may give, -- http://chris.chiasson.name/
- References:
- Re: finite differencing of a PDE system
- From: Oliver Ruebenkoenig <ruebenko@uni-freiburg.de>
- Re: finite differencing of a PDE system