Thanks Ben and Roy, I'll have a go at it tomorrow. - Dave
Kirk, Benjamin (JSC-EG311) wrote: >> - Add a new enum SCALAR to FEFamily (or alternatively, a new enum SCALAR >> to Order)? > > Something like that sounds good... This is a single scalar value coupled to > *all* other DOFs? > >> - Short circuit all the loops over elements for DOF counting in DofMap >> for SCALAR variables, and instead store the dof index of each SCALAR >> variable in a vector in DofMap? > > I would think the DofMap needs to store a vector of scalar indices, yeah.... > >> - However, I can't see where in the code one should compute the dof >> index of a SCALAR variable in the first place? > > Well, after the typical dof indexing each processor knows the local number > of Dofs and their global Dof indices, [0, n_global_dofs) so don't the > scalars get numbered sequentially in > [n_global_dofs, n_global_dofs+n_scalars) ? > >> - Ben, regarding setting the nonzero count and the number of rows that >> you mentioned; where is this controlled? In SparsityPattern? > > Yeah, the sparsity pattern is constructed, potentially handed off to > initialize matrices, then the nonzeros are counted, and it is removed to > save storage. > > Everything should fall through provided: > > (1) DofMap::dof_indices() tacks on the scalar indices for an element when it > is called, since you are expecting them to be coupled to all elemend dofs, > and > (2) n_scalar additional, *full* rows are added at the end of the sparsity > pattern. > > I think it would be pretty easy to code up and try in serial, not sure at > what point in parallel we will need to get smarter with the load balancing. > probably round-robbin'ing the scalars across processors is a better idea > than putting them continuously at the end, and thus in the last processor's > memory... > > -Ben > > So at the end of the sparsity pattern construction we a > > ------------------------------------------------------------------------------ Stay on top of everything new and different, both inside and around Java (TM) technology - register by April 22, and save $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. 300 plus technical and hands-on sessions. Register today. Use priority code J9JMT32. http://p.sf.net/sfu/p _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
