I want to do evaluate a form like this, arising from poisson equation with variable coefficient:
k * dot(grad(v),grad(u))*dx To do this, I define k as cellElement = FiniteElement("Discontinuous Lagrange", "triangle", 0) k = Function(cellElement) Now I want to define values of k dependent on material type of cell. This is the link I cant figure out how to do. -Jehanzeb On Sun, Jun 14, 2009 at 5:50 PM, Jehanzeb Hameed<jhame...@illinois.edu> wrote: > I am still struggling with this.... > > I am trying to store subdomain identifiers in meshdata object, so that > they get updated when the mesh is refined. To do this, I have a file, > mesh.xml. In that file, there is a tag named "data". The "data" tag > has a child "array" with name = "material indicators". So, now when I > create mesh, will my meshdata have this array? > > And how do I create cell dependent functions. The example in Dolfin > user manual seems outdated. I think I need to use UFCfunction, but > what do I pass as Function arguement to its constructor (if > UFCfunction is indeed the correct way to go). > > -Jehanzeb > > On Thu, Jun 11, 2009 at 11:55 AM, Bartosz Sawicki<sawic...@iem.pw.edu.pl> > wrote: >> Jehanzeb Hameed wrote: >>> >>> Hello, >>> >>> I am new to Dolfin, and was wondering how subdomains are supported as >>> regards to mesh reading and refinement. In my case, I will have a >>> mesh, with 2 subdomains. Each cell has an identifier indicating which >>> domain it belongs to. Looking at the examples, it seems I will need to >>> store domain identifiers in a separate xml file. Is that correct? >> >> Subdomain identifiers can be stored in different ways, as a separate >> MeshFunction, or in the MeshData structure. >> I prefer MeshData, because it is directly included in the Mesh object. >> You can also store boundary indicators using MeshData structure, see >> demo/pde/bcs. >> >>> With regard to mesh refinement, I assume I will be able to define >>> subdomains for each domain based on cell identifiers. Now, when I >>> refine the mesh, will the subdomains also be updated (i.e. will dolfin >>> know what domain the new cells belong to) ? >> >> If you name your MeshFunction "material indicators" it will be transformed >> to follow refined mesh. Arrays which store boundary indicators will be >> updated too. >> See LocalMeshRefinement::transformMeshData() >> >>> Also, is there a way to read archives of this list? >> >> Yes, there is http://www.fenics.org/pipermail/dolfin-dev/ >> >> regrds. >> BArtek >> >> >>> >>> Thanks, >>> -Jehanzeb >>> _______________________________________________ >>> DOLFIN-dev mailing list >>> DOLFIN-dev@fenics.org >>> http://www.fenics.org/mailman/listinfo/dolfin-dev >> >> > _______________________________________________ DOLFIN-dev mailing list DOLFIN-dev@fenics.org http://www.fenics.org/mailman/listinfo/dolfin-dev