Projecting into a quadrature space

[dokken]

The following works for me:

import dolfin as df

df.parameters["form_compiler"]["representation"] = "quadrature"
mesh = df.UnitSquareMesh(10, 10)

# Step 1: Create a Quadrature element specifying the quadrature scheme

quad_element = df.VectorElement(
    "Quadrature", mesh.ufl_cell(), degree=4, quad_scheme="default"
)

V = df.FunctionSpace(mesh, quad_element)

u = df.TrialFunction(V)

uf = df.Function(V)

v = df.TestFunction(V)

f = df.Expression(("sin(x[0])*cos(x[1])", "cos(x[0])*sin(x[1])"), degree=4)

dx = df.dx(metadata={"quadrature_degree": 4})
df.solve(
    df.inner(u, v) * dx == df.inner(f, v) * dx,
    uf,
)

print("Quarature Test finished successfully!")