On Wed, 26 Feb 2014 17:58:53 +0100 Jan Blechta <[email protected]> wrote:
> On Wed, 26 Feb 2014 15:50:32 +0100 > Heinz Zorn <[email protected]> wrote: > > > Running the given code gives the attached result. Here is the code > > once more (the first time it was hidden in the link below, sorry). > > There is missing Function.update() somewhere in DirichletBC > implementation. For a workaround, see the code below. I'll report > a bug. Reported as https://bitbucket.org/fenics-project/dolfin/issue/263/dirichletbc-forgets-to-call-_g-update Jan > > > > > from dolfin import * > > > > mesh = UnitCubeMesh( 10, 10, 10 ) > > > > V = VectorFunctionSpace( mesh, "CG", 1 ) > > > > u0 = Expression(("x[0]","0","0")) > > u0 = project( u0, V ) > u0.update() > > Jan > > > > > def u0_boundary(x, on_boundary): > > return on_boundary > > bc = DirichletBC(V, u0, u0_boundary) > > > > def sigmaIso( u, lmbda, mu ): > > return 2*mu*sym(grad(u))+lmbda*tr(grad(u))*Identity(u.cell().d) > > > > E = 100 > > nu = 0.3 > > mu = E/(2.0*(1.0+nu)) > > lmbda = E*nu/((1.0+nu)*(1.0-2.0*nu)) > > > > u = TrialFunction( V ) > > v = TestFunction( V ) > > pde = inner( sigmaIso(u,lmbda,mu), sym(grad(v)) )*dx > > a, L = system(pde) > > u = Function( V ) > > problem = LinearVariationalProblem(a, L, u, bc) > > solver = LinearVariationalSolver(problem) > > solver.parameters["linear_solver"] = "lu" > > solver.parameters["preconditioner"] = "none" > > > > solver.solve() > > > > fileu = File( "u.pvd" ) > > fileu << u > > > > Am 26.02.2014 15:36, schrieb Jan Blechta: > > > On Wed, 26 Feb 2014 15:25:01 +0100 > > > Heinz Zorn <[email protected]> wrote: > > > > > >> Hello, > > >> > > >> even using LU as linear solver does not give the right solution. > > >> It looks like the Dirichlet condition is set to zero at the > > >> borders of the mesh partition. > > > And how should we reproduce it? > > > > > > Jan > > > > > >> Heinz > > >> > > >> Am 26.02.2014 15:05, schrieb Jan Blechta: > > >>> Hi, > > >>> > > >>> I encountered crashes (segfaults or PETSc errors 76 or 77) when > > >>> using hypre with OpenMPI 1.4.3 supplied with Ubuntu Precise. The > > >>> recompilation of the whole stack of libraries with OpenMPI 1.6.5 > > >>> solved the issue. > > >>> > > >>> Try switching to another preconditioner to check the hypothesis. > > >>> > > >>> Jan > > >>> > > >>> > > >>> On Wed, 26 Feb 2014 12:15:35 +0100 > > >>> Heinz Zorn <[email protected]> wrote: > > >>> > > >>>> Hello everybody, > > >>>> > > >>>> I have got a problem with the attached code when it is run in > > >>>> parrallel using mpirun. The more processes I use, the more > > >>>> often it crashes with the message: > > >>>> > > >>>> Traceback (most recent call last): > > >>>> File "test.py", line 32, in <module> > > >>>> solver.solve() > > >>>> RuntimeError: > > >>>> > > >>>> *** > > >>>> ------------------------------------------------------------------------- > > >>>> *** DOLFIN encountered an error. If you are not able to resolve > > >>>> this issue *** using the information listed below, you can ask > > >>>> for help at *** > > >>>> *** [email protected] > > >>>> *** > > >>>> *** Remember to include the error message listed below and, if > > >>>> possible, *** include a *minimal* running example to reproduce > > >>>> the error. *** > > >>>> *** > > >>>> ------------------------------------------------------------------------- > > >>>> *** Error: Unable to successfully call PETSc function > > >>>> 'KSPSolve'. *** Reason: PETSc error code is: 76. > > >>>> *** Where: This error was encountered inside > > >>>> /build/buildd/dolfin-1.3.0+dfsg/dolfin/la/PETScKrylovSolver.cpp. > > >>>> *** Process: 11 > > >>>> *** > > >>>> *** DOLFIN version: 1.3.0 > > >>>> *** Git changeset: unknown > > >>>> *** > > >>>> ------------------------------------------------------------------------- > > >>>> Using only few processes the programm terminates properly, but > > >>>> the results are obviously not correct. The installation is the > > >>>> ppa installation on a compute server running ubuntu 13.10 > > >>>> server. It seems that commenting out line 8 and using the > > >>>> Expression to define the boundary condition solves the problem. > > >>>> > > >>>> Please tell me if any further information is needed or if I > > >>>> should post this problem anywhere else. > > >>>> > > >>>> Thanks in advance, > > >>>> Heinz Zorn > > >>>> > > >> > > _______________________________________________ > fenics mailing list > [email protected] > http://fenicsproject.org/mailman/listinfo/fenics _______________________________________________ fenics mailing list [email protected] http://fenicsproject.org/mailman/listinfo/fenics
