On Wed, Aug 28, 2013 at 8:46 AM, Roy Stogner <[email protected]>wrote:
> > On Wed, 28 Aug 2013, Praveen C wrote: > > > I found that TransientExplicitSystem does not have any mass matrix. I > wrote > > my explicit dg code with TransientLinearImplicitSystem and it works. > > However I end up computing mass matrix every time step > > Hmm... it would be easy enough for you to add an "already_computed" > flag and then skip the mass matrix assembly after the first time it's > turned on. > > > and I am not able to solve the matrices at element level. > > This, on the other hand, would not be so easy. Your proposed > alternative looks uglier but is probably much more efficient. > > > I want to use the TransientExplicitSystem. I want to store the mass > matrix > > as > > > > std::vector< DenseMatrix<Real> > > > > > with one small mass matrix per element. I can then solve at element level > > using cholesky_solve function available in DenseMatrix. But where do I > > store this matrix? > > Personally, I'd make a subclass of TransientExplicitSystem with that > as a member object; there are lots of good options though. > Are you planning to do adaptivity ever? The indexing into this std::vector may get a bit tricky in that scenario... Also, when running in parallel, you probably don't have to store mass matrices for non-local elements, but if you use a vector you'll waste a lot of space storing empty mass matrices. -- John ------------------------------------------------------------------------------ Learn the latest--Visual Studio 2012, SharePoint 2013, SQL 2012, more! Discover the easy way to master current and previous Microsoft technologies and advance your career. Get an incredible 1,500+ hours of step-by-step tutorial videos with LearnDevNow. Subscribe today and save! http://pubads.g.doubleclick.net/gampad/clk?id=58040911&iu=/4140/ostg.clktrk _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
