output to matlab readable format

[Barry Smith]

    No it is not. The (row, column, value) format is a silly relic  
from the 1980s; it is completely unscalable and slow to parse.

   For SEQAIJ matrices you can use the matrix format  
PETSC_VIEWER_ASCII_MATRIXMARKET to print the matrix. But it is not
supported for other matrices types (though could be easily added). I  
don't know which is sadder, that other formats don't support it or
that someone actually added it for SeqAIJ :-(

    Barry


On Feb 24, 2009, at 3:40 PM, Matthew Knepley wrote:

> That is the default ASCII format.
>
>   Matt
>
> On Tue, Feb 24, 2009 at 2:55 PM, Yixun Liu <enjoywm at cs.wm.edu> wrote:
> You mean PETSc has no option to only output non-zero values with the
> format (row, column, value)?
>
> Khan, Irfan wrote:
> > I don't think so. Petsc has its own way to output matrix  
> information in binary format that is platform independent.
> > However, I found that after loading into matlab, you can save or  
> output the matrix in a format that you want.
> >
> > Irfan
> >
> > ----- Original Message -----
> > From: "Yixun Liu" <enjoywm at cs.wm.edu>
> > To: "PETSc users list" <petsc-users at mcs.anl.gov>
> > Sent: Tuesday, February 24, 2009 3:39:51 PM GMT -05:00 US/Canada  
> Eastern
> > Subject: Re: output to matlab readable format
> >
> > Thanks!
> >
> > Can I save matrix into (row, column, value) format?
> >
> >
> > Khan, Irfan wrote:
> >
> >> You will need to open a binary file to output the data. Try the  
> following.
> >>
> >>
> >>        PetscViewer viewer;
> >>        ierr   =  PetscViewerBinaryOpen(PETSC_COMM_WORLD,  
> "matrix", FILE_MODE_WRITE, &viewer);
> >>        ierr   =  MatView(Amat,viewer);
> >>        PetscViewerDestroy(viewer);
> >>
> >> In order to load the file into matlab do the following
> >>
> >> % $PETSC_DIR/bin/matlab/PetscBinaryRead("<path_to_file>")
> >>
> >> Irfan
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >>
> >> Hi,
> >> I use the following code to output matrix into file which can be  
> read by
> >> matlab,
> >>
> >> PetscViewer aviewer;
> >>       PetscViewerCreate(PETSC_COMM_WORLD, &aviewer);
> >>       PetscViewerSetType(aviewer, PETSC_VIEWER_ASCII);
> >>       // 
> PetscObjectSetName((PetscObject)sparseMechanicalStiffnessMatrix,
> >> aname);
> >>       PetscViewerSetFormat(aviewer, PETSC_VIEWER_ASCII_MATLAB);
> >>       PetscViewerFileSetName(aviewer, aname);
> >>       MatView(sparseMechanicalStiffnessMatrix, aviewer);
> >>       PetscViewerDestroy(aviewer);
> >>
> >>
> >>
> >> The error is ASCII format file doesn't allow the matrix exceeds 512
> >> rows. So I change PETSC_VIEWER_ASCII to PETSC_VIEWER_BINARY, but  
> it seem
> >> that PETSc outputs to screen.
> >>
> >> Thanks.
> >>
> >>
>
>
>
>
> -- 
> 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