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<div>Check your petsc matrix before dumping the data by adding </div>
<div>MatView(A,PETSC_VIEWER_STDOUT_WORLD);<br>
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<div>immediately after calling MatAssemblyEnd().</div>
<div>Do you see a correct parallel matrix?</div>
<div>Hong</div>
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<div dir="ltr" class="gmail_attr">On Fri, May 17, 2019 at 10:24 AM Emmanuel Ayala via petsc-users <<a href="mailto:petsc-users@mcs.anl.gov">petsc-users@mcs.anl.gov</a>> wrote:<br>
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<div dir="ltr">Hello,</div>
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<div dir="ltr">I am a newby with PETSc. I want to check some matrices generated in PETSc, using MatLab.</div>
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<div dir="ltr">I created a matrix A (MATMPIAIJ), the partition is defined by PETSc and I defined the global size.</div>
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<div dir="ltr">Then, I used the next code to save in binary format the matrix from PETSc:</div>
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<div dir="ltr">PetscViewer viewer;</div>
<div dir="ltr">PetscViewerBinaryOpen(PETSC_COMM_WORLD, "matrix", FILE_MODE_WRITE, &viewer);</div>
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<div dir="ltr">After that (I think) MatView writes in the viewer:</div>
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<div dir="ltr">MatView(A,viewer);</div>
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<div dir="ltr">Then I laod the matrix in MatLab with PetscBinaryRead().</div>
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<div dir="ltr">For one process everything is Ok, I can see the full pattern of the sparse matrix (spy(A)). But when I generate the matrix A with more than one process, the resultant matrix only contains the data from the process 0.</div>
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<div dir="ltr">What is the mistake in my procedure?</div>
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<div dir="ltr">1. I just want to export the PETSc matrix to MatLab, for any number of process.</div>
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<div dir="ltr">Regards.</div>
<div dir="ltr">Thanks in advance, for your time.</div>
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