problem with Fenics 1.4.0

Question

Hi i'm having problems with Fenics 1.4.0, my code was working with the previous version. I have this error and I have no idea what is the problem, can you help? Here is the error. Thank you.

Traceback (most recent call last):
File "robin.py", line 594, in
LV = assemble(L)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/dolfin/fem/assembling.py", line 230, in assemble
cell_domains, exterior_facet_domains, interior_facet_domains)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/dolfin/fem/assembling.py", line 80, in _create_dolfin_form
mesh=mesh)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/dolfin/fem/form.py", line 98, in init
= jit(form, form_compiler_parameters)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/dolfin/compilemodules/jit.py", line 62, in mpi_jit
return local_jit(*args, **kwargs)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/dolfin/compilemodules/jit.py", line 126, in jit
return jit_compile(form, parameters=p)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/ffc/jitcompiler.py", line 77, in jit
return jit_form(ufl_object, parameters)
File "/usr/site-local/FEniCS-1.4.0/lib64/python2.7/site-packages/ffc/jitcompiler.py", line 103, in jit_form
form_data = form.compute_form_data()
File "/usr/site-local/FEniCS-1.4.0/lib/python2.7/site-packages/ufl/form.py", line 169, in compute_form_data
self._form_data = preprocess(self, object_names=object_names)
File "/usr/site-local/FEniCS-1.4.0/lib/python2.7/site-packages/ufl/algorithms/preprocess.py", line 149, in preprocess
form_data.subdomain_data = join_subdomain_data(form.integrals(), form.domains())
File "/usr/site-local/FEniCS-1.4.0/lib/python2.7/site-packages/ufl/algorithms/preprocess.py", line 98, in join_subdomain_data
l = l2l[None]
KeyError: None

Comments

Please provide the form for L.

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Please edit your question and include a complete but minimal example that reproduces the problem.

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Thank you, actually I found a solution to the problem but I can not explain what was the problem exactly. The form L is too complicated to reproduce here but I will try to explain in a simple way what I did to solve the problem, maybe you have an explanation.

So I have a domain Omega, let's say a square with a rectangle mesh.

mesh = RectangleMesh(0, 0, 1, 1, N, N)

The associated measure is called:

dtotal = Measure("dx")

Then this domain is splitted in two domains Omega0 and Omega1, marked 0 and 1, respectively, and I define the associated measures:

dx = Measure("dx")[domains]

Then I am defining a form L using a sum, for instance to make it simple:

for k  in range(0,10):
    L +=  u[k]**2 * dtotal + u[k] * dx(0)

but I need to initialize L, so I add before that

L     = 0 * psi * dx(0)

where psi is some appropriate test function.

This initialization of L was actually creating the mistake. I changed it to

L     = 0 * psi * dtotal

so in other words, using the measure of the larger domain and now it is fine. In the previous version of Fenics there was no problem with this.

cheers