On 17.08.2012 15:30, Jed Brown wrote: > > Sorry, I misinterpreted what you want. PC_COMPOSITE_MULTIPLICATIVE > re-evaluates the residual after applying the first stage of the > preconditioner. Do you _really_ want to just apply one preconditioner > after the next? You can use PC_COMPOSITE_SPECIAL, but read this man > page and understand why your preconditioner has that form. > http://www.mcs.anl.gov/petsc/petsc-current/docs/manualpages/PC/PCCompositeType.html
Jed, I've seen this, but I'm not sure is it fits me. What I would like to do is very simple: every N iterations I want to take current solution vector *x*_i from KSP and calculate: *x*_i = *x*_i + *c*, where *c* is a correction vector. I want to be able to apply other preconditioners in a usual way. Is it possible? -- Regards, Alexander -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20120817/4c2f2da5/attachment.html>
