On Thu, Mar 29, 2012 at 9:09 PM, Andrew Spott <andrew.spott at gmail.com>wrote:
> Thanks again for the quick reply! Thankfully I don't have a mass matrix, > I'm just solving the schrodinger equation. > Depending on how you discretize, you can have a mass matrix for Schrodinger. Matt > Thanks again. > > -Andrew > > On Mar 29, 2012, at 8:07 PM, Barry Smith wrote: > > > > > On Mar 29, 2012, at 8:58 PM, Andrew Spott wrote: > > > >> This: > http://www.mcs.anl.gov/petsc/petsc-3.2/src/ts/examples/tutorials/ex4.c.html > Looks like what I'm interested in doing, though I would like to use the > latest. > > > > With this simple a situation using the current version or switching to > dev is both fine. The changes you would have to make are small > > > >> When is Petsc 3.3 (or 3.4, I'm not sure how your versioning works) > coming out? Is the dev version stable enough (in API and in execution) to > be used? > > > > The dev version is always stable enough to use :-). At this point yes > because we are in the testing phase for the next release. > > > >> > >> Until then, does the 3.2 version of the TS interface work? (the link > above, and the corresponding one for petsc-dev don't appear to have much > changed between them). > > > > Yes. > > > > Barry > > > > Note that in 3.2 if you have a mass matrix (for example M U_t = A > U_xx)how to formulate the problem is different between 3.2 and dev so I > would recommend working immediately with dev. But for simple U_t = > something, 3.2 is fine and then you can change it slightly for the next > release. > > > >> > >> Thanks for the prompt reply, > >> > >> -Andrew > >> > >> On Mar 29, 2012, at 7:37 PM, Barry Smith wrote: > >> > >>> > >>> Andrew, > >>> > >>> These are outdated manual pages; you'll want to avoid this. > >>> > >>> Jed and Emil have done a major update of the TS interface and > solvers, much more powerful and less confusing. > >>> > >>> Likely you'll want to use TSSetIFunction() and TSSetIJacobian() > http://www.mcs.anl.gov/petsc/petsc-dev/docs/manualpages/TS/index.html and > work with petsc-dev http://www.mcs.anl.gov/petsc/developers/index.html > >>> > >>> > >>> > >>> Barry > >>> > >>> On Mar 29, 2012, at 8:09 PM, Andrew Spott wrote: > >>> > >>>> In the Petsc manual, there is a TSSetMatrices function, however there > is no further documentation for it. > >>>> > >>>> It is referenced in the manual as: > >>>> > >>>> TSSetMatrices(TS ts, > >>>> Mat A,PetscErrorCode > (*frhs)(TS,PetscReal,Mat*,Mat*,MatStructure*,void*), Mat B,PetscErrorCode > (*flhs)(TS,PetscReal,Mat*,Mat*,MatStructure*,void*), MatStructure flag,void > *ctx) > >>>> > >>>> However, what is passed to the function pointers isn't mentioned > anywhere, and it isn't in the online documentation. > >>>> > >>>> Also, I assume that "MatStructure flag" tells if the structure of A > and B are the same or different, if B is PETSC_NULL, is flag > "SAME_NONZERO_PATERN" or is it different? (B can be considered to not > exist, or to exist as an identity matrix, hence the confusion). > >>>> > >>>> How does the ctx work? Is the same context passed to frhs each time? > >>>> > >>>> Thanks for the help. > >>>> > >>>> -Andrew > >>> > >> > > > > -- 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-users/attachments/20120329/4cefe5f0/attachment-0001.htm>
