mesh = RectangleMesh(n0, n0, Lx, Ly,  reorder = None)

I know that I can impose zero Dirichlet boundary conditions using

bc = DirichletBC(Vcg, 0.0, "on_boundary")

However, if I impose a mesh created by gmsh (the circle I asked about last week) say using

mesh = Mesh("circle.msh")

I get the right geometry but it doesn't impose the zero boundary conditions.

Is there something you need to do to impose these boundary conditions?

Cheers, Francis
------------------
Francis Poulin                    
Associate Professor
Department of Applied Mathematics
University of Waterloo

email:           fpoulin@uwaterloo.ca
Web:            https://uwaterloo.ca/poulin-research-group/
Telephone:  +1 519 888 4567 x32637