[petsc-users] MatCopy and MatSetValue consume most 99 percentage of runtime

[Jed Brown]

On Wed, Apr 20, 2011 at 05:08, Vijay S. Mahadevan <vijay.m at gmail.com> wrote:

> Barry, just to confirm, are you saying that MatZeroEntries would
> nullify the preallocation completely if called before
> AssmeblyBegin/End ?
>

I can't think of a way that would happen. It may zero more entries than
necessary, but it shouldn't forget the preallocation. Note that the
preallocation in DMGetMatrix() and many other libraries actually insert
explicit zeros in the locations it has preallocated.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20110420/55b4dceb/attachment.htm>