On Thu, Jul 17, 2014 at 6:35 AM, Italo Tasso < [email protected]> wrote:
> I have two matrices: matrix A is 4n x 4n and matrix C is n x n. I want to > set the values of A using the values of C, like this: > > A[4i+k][4j+k] = C[i][j] > 0 < i < n > 0 < j < n > 0 < k < 3 > > How can I do this efficiently? > The best way to do it is to assemble directly into the big matrix. You can do this by explicitly translating indices, or use something like this http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/Mat/MatGetLocalSubMatrix.html Thanks, Matt -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
