On Tue, Mar 6, 2012 at 08:50, Abdul Hanan Sheikh <hanangul12 at yahoo.co.uk>wrote:
> I had to implement the projection preconditioner (P = I - A*R*(A_H)^1 *P) > along with an standard preconditioner (M). > And I read in some thread of users list that multilevel preconditioner can > better > handled by PCMG too, thus > I had tried to implement the later (M) as pre smoother, where as the > earlier (P) as CGC in PCMG framework. > > 1. Does it make sense ? > or the coarse grid correction of PCMG only does this part: R*(A_H)^1 *P > ?? > 2. How can I adapt my projection preconditioner (P) as (P1 = I - > A*R*(A_H)^1 *P + R*(A_H)^1 *P ) ? It's still not clear exactly what you want the method to do. PCMG can do additive or multiplicative cycles. For more general composition, see http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCCOMPOSITE.html http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCGALERKIN.html I see the man pages are lacking details, the user's manual has more details. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120306/daffdce1/attachment.htm>
