Hi, Could you also share the whole output before and after the "error in assembly string" message?

BR Kostas On Fri, Nov 29, 2019 at 1:31 PM Davide Manfredo <manfredo.dav...@gmail.com> wrote: > Dear Getfem++ Users, > > I have the following bricks, in my assembled and working matrix, using > MATLAB Interface > > gf_model_set (md, 'add nonlinear generic assembly brick', mimLp, > 'Div_uv.Test_pv', -1, 0, 0); > gf_model_set (md, 'add nonlinear generic assembly brick', mimLv, > '-pv.Div_Test_uv', -1, 0, 0); > > where uv and pv are two of the four unknowns of the system, and the mesh > is a straight segment LambdaM defined as follows > Lambdaref= 0:1/(nbsk-1):1; > LambdaM=gf_mesh('cartesian', Lambdaref); > > and mimLp and mimLv are the integration methods for uv and pv respectively > over LambdaM. > uv is approximated by 'FEM_PK(1,1)' > pv is approximated by 'FEM_PK_DISCONTINUOUS(1,0)' > > This is running properly, my problem starts when I modify the mesh. > In fact, I tried to define an empty mesh to which I added geometrical > properties and points one by one, in the following way > > LambdaM=gf_mesh('empty',3); %Here Lambda is of dimension 3 because it's > supposed to be a segment embedded in a 3D domain > gf_mesh_set(LambdaM, 'add point', [point vect]); > GT=gf_geotrans('GT_PK(1,1)'); > > Running the same codes as above I received the error "error in assembly > string". > Do you have any idea what the problem could be? I think that the problem > lies in the mesh definition, but I can't see where specifically since other > bricks work perfectly and with the other mesh definition I didn't have any > problem. > > Thank you very much for your support, > Davide Manfredo >