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UFLException: Sub elements must live on the same domain (FOR NOW)?

+2 votes

Hi (again!),
I have a basic question related to the old one http://fenicsproject.org/qa/3561/mixed-spaces-over-different-meshes?show=3561#q3561

Using Dolfin 1.5 ubuntu ppa I still have the UFLException:

Sub elements must live on the same domain (for now) with the script

from dolfin import *

mesh1 = UnitIntervalMesh(4)
mesh2 = UnitIntervalMesh(2)

V1 = FunctionSpace(mesh1, "CG", 2)    # 9 Lagrange global functions of degree 2
V2 = FunctionSpace(mesh2, "CG", 1)    # 3 Lagrange global functions of degree 1

V = V1 * V2

(u1, u2) = TrialFunctions(V)
v1 = TestFunction(V1)

a =  (inner(grad(u1), grad(v1)) * dx) + (inner(grad(u2), grad(v1)) * dx) 
A = assemble(a)

V1_dofs = V.sub(0).collapse(mesh1)[1].values()
V2_dofs = V.sub(1).collapse(mesh2)[1].values()

print 'V1 dofs = ', V1_dofs
print 'V2 dofs = ', V2_dofs

print 'A = ', A.array()

It is possible to install an experimental Dolfin version with this feature (using
dorsal)?

How can I workaround this problem for now?

Thank you

asked Feb 9, 2015 by Andre Machado FEniCS User (1,040 points)
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