On Fri, Feb 17, 2012 at 06:54, Thomas Witkowski < thomas.witkowski at tu-dresden.de> wrote:
> Maybe some related question: Most textbooks write that the compatibility > condition to solve a system with constant null space is that the right hand > side has zero mean value. Today I read part of the Multigrid-book written > by Trottenberg, and there the condition is written in a different form (eq > 5.6.22 on page 185): the integral of the right hand side must be equal on > the whole domain and on the boundary. Does any of you have an explanation > for this condition? Is there a book/paper that considers the compatibility > condition in more details? It's common to project the null space out of the right hand side (yielding a "consistent" right hand side). -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120217/131d0846/attachment.htm>
