On 6/14/06, Christophe Picard <picard2 at llnl.gov> wrote: > > Hello, > > I have been trying to used DMMG and DA in the following way. > I have a DA with several degree of freedom, and several of them have the > same > jacobian but different RHS (what I want to do is solve Ax1=b1(x1,x,2,x3), > Ax2=b2(x1,x2,x3)). > So how does DMMGsolve handle that?
I am not sure I understand completely what you want, but I will start with the DA. DA objects only encode a data layout. All data resides in Vec and Mat objects. So, if you have several fields that you want to solve separately, then create a DA with 1 dof, and use several Vecs. Since the Jacobian is the same, you will have 1 Mat. Matt Since x1,x2,x3 are DA variables, but I want to solve only x1 and x2 using > the > same Jacobian, I figured that I can have some kind of switch in the > definition of the RHS function that will make the selection, and calling > dmmgSolve several times, but by modifyng the switch trough DMMGSetUser and > DMMGGetUser before each call. But then where the output of the solve > operation is stored? The way I understand it now is that it is > overwritting > x1. Am I right? > Is there a way to solve x1 and x2 simultaneously, I mean by only 1 call of > dmmgSolve, and without solving x3? > > I hope I am not too confusing. > > Thank you, > > Christophe > --- > > > -- "Failure has a thousand explanations. Success doesn't need one" -- Sir Alec Guiness -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20060614/80ef097d/attachment.htm>
