Matrix add/set

Question

Matrix has functions add/set to change the values inside the Matrix. But I have to add/set a block of matrix. Can I just add/set a sparse matrix (stored in CSR data structure)?

I know I can add the element one by one in sparse matrix, but I think the time cost will be huge, because there are a lot of data movement in each add operation. Is there a simpler way to do it?

Answer 1

The GenericMatrix::add/set functions take dense blocks. See http://fenicsproject.org/documentation/dolfin/1.3.0/cpp/programmers-reference/la/GenericMatrix.html#GenericMatrix::set__doubleCP.dolfin::la_indexCP.dolfin::la_indexCPCP.