I use the data in the vectors for things besides pure vector operations. In the context of a sub-iteration scheme for an incompressible solver, I want to use the values stored in the vector at the previous iteration to construction the non-linear term. This requires copying not just the local portion of the vector in the u(k)->u(k-1) operation, but the ghosts as well. Doesn't copying the entire ghosted vector make sense in this context?
John On Fri, Mar 1, 2013 at 8:09 AM, Jed Brown <jedbrown at mcs.anl.gov> wrote: > On Wed, Feb 27, 2013 at 4:56 PM, John Mousel <john.mousel at gmail.com>wrote: > >> Is there a possibility of adding a wrapper function around a few basic >> vector operations such as VecCopy, VecAXPY, VECAXPYPZ... to operate on >> ghosted vectors? I perform a lot of vector operations including the ghost >> region to avoid communication. >> > > Can you explain the context where operating with local forms in this way > makes sense? Usually you would either be working locally, in which case you > copy between local forms (or purely local work vectors) or you are > operating globally in which case there is nothing to gain by applying > operations to the local form. > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20130301/d707b7c4/attachment.html>
