Project creates different results

8

I see some of the variability you get as well. However, there are a few things I would like you to adress:

  • You are projecting the derivative of a function into the same space as your original function. This will not be a good representation, as the deriviatve of a CG-2 function is in a DG-1 space. See for instance: Interpolate the gradient of a dolfin function - #3 by VKTR
  • You should check that the interpolation of func2d into func3d gives a consistent result before trying to project the derivative.