----- Boyce Griffith <griffith at cims.nyu.edu> wrote:
>
>
> 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.
My apologies,the above code snippet is incorrect. Jed has already pushed a
fix for this and i'm working on it too. Sorry about the confusion.
Shri
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
