dof with singular mesh

[Edouard Oudet]

Dear getfem users,

Using the python interface of Getfem++, I obtained surprising results 
related to the representation of degrees of freedom for a singular mesh 
associated to a square with two circular holes. One of the hole has a 
very small radius see picture

https://www-ljk.imag.fr/membres/Edouard.Oudet/download/singmesh.png

This mesh can be downloaded at

https://www-ljk.imag.fr/membres/Edouard.Oudet/download/savemesh.mesh

Using the following instructions

filemesh = '/tmp/savemesh.mesh'
tmesh = getfem.Mesh("load", filemesh)
tmeshfem = getfem.MeshFem(tmesh, 1)
tmeshfem.set_fem(getfem.Fem('FEM_PK(2, 4)'))
pdof = getfem.MeshFem.get(tmeshfem, 'basic dof nodes')

and plotting these pdof points I obtained the following picture around 
the small circle

https://www-ljk.imag.fr/membres/Edouard.Oudet/download/savemesh.mesh

As it can be observed some dof are missing.. I do not get this problem 
for a degree smaller than 4.
Any suggestions are welcome,

best,

Edouard.

--
Edouard Oudet : http://www-ljk.imag.fr/membres/Edouard.Oudet/
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