Hallo, I have a singular right-hand side. In order to approximate it via quadrature, I want to compute an approximation on a fine mesh. Thereafter, I want to project it onto the coarser mesh (so the test functions cannot see any difference between the approximation on the fine and coarse mesh.
Blockquote
from dolfin import *
meshCoarse = UnitSquareMesh(2,2)
meshFine = refine(meshCoarse)
f = Expression(‘pow((x[0]-.5)(x[0]-.5)+(x[1]-.5)(x[1]-.5)+pow(10,-14),-1.5/2)’,degree = 3) #f(x,y) = |(x,y)-(.5,.5)|^-1
DG_coarse = FunctionSpace(meshCoarse,“DG”,1)
DG_fine = FunctionSpace(meshFine,“DG”,1)
f_fine = project(f,DG_fine) #Approximate f on fine mesh
f_coarse = project(f_fine,DG_coarse) #Project the approximation of f onto the coarse mesh
print assemble(f_fine *dx)
print assemble(f_coarse *dx)
However, project(f_fine, DG_coarse) does not compute the L2 projection. How can I circumvent this issue? Best regards, Johannes