Mathematica Technical Question
- To: mathgroup at smc.vnet.net
- Subject: [mg7234] Mathematica Technical Question
- From: "Mark T. Lusk" <mlusk at druid.Mines.EDU>
- Date: Sat, 17 May 1997 19:13:25 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
First of all, thanks for setting up and supporting the Mathematica User Group. I have just discovered it. I am trying to use NDSolve to evaluate solutions to fourth order reaction diffusion equations (one time derivative, four spatial derivatives, nonlinear in either the dependent variable or its derivative). I have used this routine successfully on second order, nonlinear pde's and have tried just about everything to get the call to solve such Cahn-Hilliard type equations. I get all sorts of error remarks about starting step size and singularities. These are typically concluded with "Internal error: FreeExpr called on live expr". I don't even know what this means. Certainly there must be some folks out there who have used Mathematica to solve such equations succesfully. Any help would be greatly appreciated. Thanks very much. -- Mark T. Lusk Division of Engineering, Colorado School of Mines 1500 Illinois Street, Golden, CO 80401 303-273-3675 (voice), 303-273-3602 (FAX) mlusk at mines.edu http://druid.mines.edu/~mlusk/personal.html