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<div dir="ltr">I'll check it tomorrow.
<div>Hong</div>
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<div dir="ltr" class="gmail_attr">On Sun, Sep 22, 2019 at 1:04 AM Pierre Jolivet via petsc-dev <<a href="mailto:petsc-dev@mcs.anl.gov">petsc-dev@mcs.anl.gov</a>> wrote:<br>
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<div style="overflow-wrap: break-word;">Jed,
<div>I’m not sure how easy it is to put more than a few lines of code on GitLab, so I’ll just send the (tiny) source here, as a follow-up of our discussion <a href="https://gitlab.com/petsc/petsc/merge_requests/2069#note_220229648" target="_blank">https://gitlab.com/petsc/petsc/merge_requests/2069#note_220229648</a>.</div>
<div>Please find attached a .cpp showing the brokenness of C=A*B with A of type MPIAIJ and B of type MPIDense when the LDA of B is not equal to its number of local rows.</div>
<div>It does [[1,1];[1,1]] * [[0,1,2,3];[0,1,2,3]]</div>
<div>C should be equal to 2*B, but it’s not, unless lda = m (= 1).</div>
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<div>Mat Object: 2 MPI processes</div>
<div> type: mpidense</div>
<div>0.0000000000000000e+00 1.0000000000000000e+00 2.0000000000000000e+00 3.0000000000000000e+00</div>
<div>0.0000000000000000e+00 1.0000000000000000e+00 2.0000000000000000e+00 3.0000000000000000e+00</div>
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<div>If you change Bm here <a href="https://www.mcs.anl.gov/petsc/petsc-dev/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line549" target="_blank">https://www.mcs.anl.gov/petsc/petsc-dev/src/mat/impls/aij/mpi/mpimatmatmult.c.html#line549</a> to the LDA of B, you’ll
get the correct result.</div>
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<div>Mat Object: 2 MPI processes</div>
<div> type: mpidense</div>
<div>0.0000000000000000e+00 2.0000000000000000e+00 4.0000000000000000e+00 6.0000000000000000e+00</div>
<div>0.0000000000000000e+00 2.0000000000000000e+00 4.0000000000000000e+00 6.0000000000000000e+00</div>
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<div>Unfortunately, w.r.t. MR 2069, I still don’t get the same results with a plain view LDA > m (KO) and a view + duplicate LDA = m (OK).</div>
<div>So there might be something else to fix (or this might not even be a correct fix), but the only reproducer I have right now is the full solver.</div>
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<div>Thanks,</div>
<div>Pierre</div>
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