Dear all, I create a very simple gmsh file: just a square with "left", "bottom", "right" and "top" boundary. I have attached two versions of the mesh. 1) neu3.msh: This has the "PhysicalNames" declared at the beginning. I get a "File is not a valid Gmsh file" error. 2) neu4.msh: This has the "PhysicalNames" declared at the end. But if I now try to set Dirichlet bc for the "left" and "right" boundary, e.g. with bc0 = DirichletBC(W.sub(0), Expression("0.0"), "right") nothing seems to happen. I guess I'm missing sth. obvious here... Thank you! Henrik Error message for neu3.msh Traceback (most recent call last): File "charge.py", line 7, in <module> mymesh = Mesh("neu3.msh") File "<decorator-gen-274>", line 2, in __init__ File "/home/hb111949/.local/lib/python2.7/site-packages/PyOP2-0.11.0_425_g64db689-py2.7-linux-x86_64.egg/pyop2/profiling.py", line 203, in wrapper return f(*args, **kwargs) File "/home/hb111949/Code/firedrake/firedrake/mesh.py", line 351, in __init__ plex = _from_gmsh(meshfile) File "/home/hb111949/Code/firedrake/firedrake/mesh.py", line 152, in _from_gmsh gmsh_plex = PETSc.DMPlex().createGmsh(gmsh_viewer) File "PETSc/DMPlex.pyx", line 115, in petsc4py.PETSc.DMPlex.createGmsh (src/petsc4py.PETSc.c:214898) petsc4py.PETSc.Error: error code 62 [0] DMPlexCreateGmsh() line 140 in /rwthfs/rz/cluster/home/hb111949/Code/petsc/src/dm/impls/plex/plexgmsh.c [0] Invalid argument [0] File is not a valid Gmsh file -- Dipl.-Math. Henrik Büsing Institute for Applied Geophysics and Geothermal Energy E.ON Energy Research Center RWTH Aachen University ------------------------------------------------------ Mathieustr. 10 | Tel +49 (0)241 80 49907 52074 Aachen, Germany | Fax +49 (0)241 80 49889 ------------------------------------------------------ http://www.eonerc.rwth-aachen.de/GGE hbuesing@eonerc.rwth-aachen.de ------------------------------------------------------