Hi, I am trying to optimize a code that solves an inhomogeneous laplacian
pde of the form :
-div ( K(x) grad(u) ) = f 0 < x,y < 1 where K(x) is a
matrix that
depends on the position
I use finite differences and the values of "f" and "u" are cell centered.
The problem is the following, since each interface is common to two cells,
and I need the value of K on the interfaces, which is taken as an harmonic
mean, I would like to compute these values only once, and then pass them as
some user context to KSPSetComputeOperators, because I am using a dmda. Any
ideas ?
