Is it possible to perform Lagrange interpolation with Fenicsx?
This is a very general question. As FEniCSx uses numpy to store arrays, you can easily use scipy.interpolate.lagrange — SciPy v1.9.1 Manual to do lagrange interpolation of your data.
Thank you for the quick answer. How do I access the numpy array for a <class 'dolfinx.fem.function.Function'>?
u = dolfinx.fem.Function(V)
print(u.x.array)
Do you also have a page for lagrange multipliers? Or is there a function for lagrange multipliers in fenicsx?
Lagrange multipliers (in real spaces) are under development, see:
For other Lagrange multipliers (say P-1), you need to write up your variational form using UFL syntax.