dolfin team mailing list archive

[Johan Hake <hake@xxxxxxxxx>]

On Friday 13 March 2009 10:14:08 Garth N. Wells wrote:
> Johan Hake wrote:
> > On Thursday 12 March 2009 23:16:11 Anders Logg wrote:
> >> On Thu, Mar 12, 2009 at 10:07:13PM +0000, Garth N. Wells wrote:
> >>> Kristian Valen-Sendstad wrote:
> >>>>> On Thu, March 12, 2009 14:25, Kristian Valen-Sendstad wrote:
> >>>>>> Hi,
> >>>>>> There seems to be a bug in the periodic boundary conditions demo
> >>>>>> located in
> >>>>>> /demo/pde/periodic/.
> >>>>>>
> >>>>>> It does not do what one would expect, and there are lots of "PETSC
> >>>>>> ERROR"s
> >>>>>> in both python and cpp.
> >>>>>
> >>>>> Do you use the latest development version? If so, I think you have
> >>>>> the same problems as the buildbot.
> >>>>>
> >>>>> Johannes
> >>>>
> >>>> Yes, I do.
> >>>> However, Johan Elon Hake came to the rescue and set the linear algebra
> >>>> backend to uBLAS, which solved the problem.
> >>>
> >>> It would be nice to figure out what the cause of the problem is with
> >>> PETSc. What are the first few lines of the error message?
> >>>
> >>> Garth
> >>
> >> I get the same thing on my machine and I guess everyone does:
> >>
> >>   Applying periodic boundary conditions to linear system.
> >>   [0]PETSC ERROR: --------------------- Error Message
> >>   ------------------------------------
> >>   [0]PETSC ERROR: Object is in wrong state!
> >>   [0]PETSC ERROR: Not for unassembled matrix!
> >>
> >> The problem is most likely a mix of calling A.ident(), getrow() and
> >> not appropriately calling apply(). It should be fairly easy to fix but
> >> I haven't had time to track it down.
> >
> > The problem started after Olas last push. Strange that a changeset that
> > only affect XML files should have any to say for the PETSc backend?
>
> apply() doesn't do anything for the uBLAS backend as there is no need to
> 'assemble' internally a sparse matrix. All the other backends require
> this. This would explain why uBLAS works.

Yes I know, and I think it is weird that this problem pops up after a push 
only touching files that handles xml files.

Johan