On 25. sep. 2010, at 02:37, Johan Hake <[email protected]> wrote:
> Hello! > > I have been experimenting with forms including spaces of Real. I am using the > Real space to calculate average values of other species across the > boundaries. > These values are then used to cacluate derived values such as fluxes across a > boundary. In this way I manage to connect two sepatated meshes (stored in the > same mesh) via the calculated flux. As everything is contained in one form I > can linearize it an use it in a Newton solver, which converges nicely. > > In this procedure I have used unknowns of Reals to caluclate other Reals. > This > is somewhat combersome when I have to express this using an integral. > > Consider: > > V = MixedFunctionSpace([FunctionSpace(mesh, "CG", 1)]+ > [FunctionSpace(mesh, "R", 0)]*3) > > u, r0, r1, r2 = split(Function(V)) > v, v0, v1, v2 = TestFunctions(V) > ... > L0 = (r0-(r2-r1))*v0*ds(1) > > Here I express r0 in terms of r1 and r2. However in the form I need to > integrate the expression over an arbitrary domain in the mesh. I am not > interested in this, as the value is not spatialy varying. Do you have any > suggestions of how to avoid this or to do it in some other manner? > It is not entirely clear to me which values that are unknown above, but if everything is known or you are just operating on real numbers, I imagine that extracting the value of the Function using values() could be simpler? -- Marie > Regards, > > Johan > > _______________________________________________ > Mailing list: https://launchpad.net/~dolfin > Post to : [email protected] > Unsubscribe : https://launchpad.net/~dolfin > More help : https://help.launchpad.net/ListHelp _______________________________________________ Mailing list: https://launchpad.net/~dolfin Post to : [email protected] Unsubscribe : https://launchpad.net/~dolfin More help : https://help.launchpad.net/ListHelp
