Thank You! 2011/9/4 Matthew Knepley <knepley at gmail.com>
> On Sun, Sep 4, 2011 at 10:08 AM, ??????? ??????? <ram at ibrae.ac.ru> wrote: > >> Hello! >> Help me please to solve my tiny problem with dmmg. >> >> In the example src/ksp/ksp/examples/tutorials/ex22.c, which is discussed >> on the 111th page of users manual, we use function >> (line 36): >> DACreate3d(PETSC_COMM_WORLD,DA_NONPERIODIC,DA_STENCIL_STAR,-3,-3,-3,PETSC_DECIDE,PETSC_DECIDE,PETSC_DECIDE,1,1,0,0,0,&da); >> to "*create the DA that stores information about the coarsest grid you >> wish to use*". >> We can see that negative dimension values (-M, -N, -P) are used "*to >> indicate that it may be set to a different value from the command line with >> -da_grid_x <M> -da_grid_y <N> -da_grid_z <P>". * >> The question is: when I use -da_grid_ M,N,P options as the size of the >> coarsest matrix, what's the size of the finest (most accurate, original >> problem) matrix? >> >> I've tried to clear this up, using VecVew on the residual vector and >> figured out, that when i'm using M,N,P as input parameters (so define the >> coarsest grid as field of M*N*P dots), I get the residual vector of size >> (4*M-3)*(4*N-3)*(4*P-3). >> Is my result correct? If yes, could you please explain why it happens in >> this way. >> > > When refinement happens, it adds a vertex between any two vertices, > starting with the mesh you provide. > > Matt > > >> Sorry if my question is incorrect. I could mix up everything at all. >> Thanks in advance! >> >> -- >> Best regards, >> Alexey Ryazanov >> ______________________________________ >> Nuclear Safety Institute of Russian Academy of Sciences >> >> >> > > > -- > 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/20110904/83350af6/attachment.htm>
