On Jan 22, 2008 11:01 PM, Yujie <recrusader at gmail.com> wrote: > Dear Matt: > > thank you for your reply. Do you have any method to generate an ascii file > of the huge sparse matrix? thanks
I think you miss my point. The PETSc function is not a bad way to generate ASCII matrices. ASCII matrices make "no sense" for large operators. Matt > Regards, > Yujie > > > > On 1/23/08, Matthew Knepley <knepley at gmail.com> wrote: > > On Jan 22, 2008 8:50 PM, Yujie <recrusader at gmail.com> wrote: > > > Hi everyone: > > > > > > #include "petsc.h" > > > PetscErrorCode PetscViewerASCIIOpen(MPI_Comm comm,const char > > > name[],PetscViewer *lab) > > > > > > #include "petsc.h" > > > PetscErrorCode PetscViewerBinaryOpen(MPI_Comm comm,const char > > > name[],PetscFileMode type,PetscViewer *binv) > > > > > > if the difference between them is that one for ASCII output and the > other > > > for Binary output, why are there different parameters? > > > > It is historical. If you want to be generic, you should use > > > > PetscViewerCreate() > > PetscViewerSetType() > > PetscViewerFileSetMode() > > PetscViewerFileSetName() > > > > which can create both. > > > > > The speed to output matrix is very fast when I use > PetscViewerBinaryOpen. > > > However, when I use PetscViewerASCIIOpen, I can't get the matrix output. > the > > > code always is running and it has taken about one day! what's the > problem? > > > thank you. > > > > ASCII files do not make sense for large matrices. You should use binary > files. > > > > Matt > > > > > Regards, > > > Yujie > > > > > > > > > > > > > > > > > -- > > 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 > > > > > > -- 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
