On Mon, 4 Feb 2008, Yujie wrote: > I am wondering a problem about unkown varialbes (x) distribution in libmesh. > Practically, you use finite element method to solve PDE, you will finally > get the linear equation Ax=b. In libmesh, if you solve it parallelly, you > need to first partition the domain, that is A is partionted. However, each > node in the cluster has all the variables x or only the part of x? Could you > give me some advice? thanks a lot.
In parallel, on each processor the solution (x) vector which PETSc uses only has the part of x whose degrees of freedom are "owned" by that processor. However the library regularly localizes that solution vector onto current_local_solution, which has the coefficients for both degrees of freedom owned by the processor and degrees of freedom which have support on any element touching an element owned by the processor. If what you really need is a vector that has every single degree of freedom on every processor, check the NumericVector API; you should be able to create a serial vector and then localize onto it to get every single DoF coefficient. --- Roy ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
