On 9/27/10 5:28 PM, Shri wrote:
> Barry,
> I've modified MatAXPY_SeqAIJ as follows when
> DIFFERENT_NONZERO_STRUCTURE flag is true (i) create a new matrix and do
> preallocation for it. For determining the number of nonzeros per row in the
> new matrix, i've used the number of nonzeros in the original two matrices.
> This is the piece of code which computes the nnz per row in the new matrix
> for(i = 0;i< m;i++) {
> nzx = xi[i+1] - xi[i]; nzy = yi[i+1] - yi[i];
> if (nzx> nzy) nnz[i] = nzy + (nzx - nzy);
> else nnz[i] = nzx + (nzy - nzx);
> }
I don't understand why this is the right thing to do. It seems like
this either sets nnz in the new matrix to be nzx or nzy, whichever is
smaller. Am I misreading this code snippet?
-- Boyce
