On Wed, Dec 14, 2011 at 4:07 PM, Philip, Bobby <philipb at ornl.gov> wrote:
> Hi: > > When doing the following operation in PETSc using FD approximations to a > Jacobian vector product > > J'(u)*a = [J(u+h*a) - J(u)]/h > Usually, we would put in F where you have J. > is there a way for the user to specify that the entries of u+h*a cannot be > negative for example? > Browsing the PETSc documentation it was not obvious whether I could do > this. > You can do whatever you want in your F function, but you should really investigate SNESVI if you have bounds on your variables. Thanks, Matt > Thanks, > Bobby -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20111214/b431a8d7/attachment.html>