How to set up boundary condition for VectorL2FESpace

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1

I tried to set up u=g on the boundary for Stokes problem. I defined the DG FEspace as follows.

V = VectorL2(mesh,order=2, dirichlet ='left|right|top|bottom',dgjumps=True) Q = L2(mesh,order=1) X = FESpace([V,Q],dgjumps=True)

When I run the code, there is a error at the following line

[quote]gfu.components[0].Set(g, BND, definedon=mesh.Boundaries(“left|right|top|bottom”))
[/quote]
VectorL2FESpace does not have an evaluator for BND!

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The code was attached.
Could you please show me how to set up the boundary condition for VectorL2FESpace or fix this error? Thank you so much.

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Attachment: fem2.ipynb

2

l2 space doesnot have dofs on the bdry. you need to impose dirichlet bc weakly

3

I’m a newbie, I don’t understand what you’ve said. Could you please tell me what ‘weakly’ meant here? Do you know any examples about imposing dirichlet bc weakly with Ngsolve? Thank you.