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Dear PETSc team:<br>
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I am working with a non-overlapping distributed plex (i.e., when I call DMPlexDistribute(), I input overlap = 0), so only vertices and edges appear as ghosts to the local ranks.</div>
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For preallocation of a parallel global stiffness matrix for FEA, I want to determine which locally owned vertices are ghosts to another rank.<br>
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From reading the paper on PetscSF (<a href="https://ieeexplore.ieee.org/document/9442258" id="LPlnkOWALinkPreview">https://ieeexplore.ieee.org/document/9442258</a>) I think I can answer my question by inspecting the PetscSF returned by DMPlexDistribute() with
PetscSFGetGraph(). I am just confused by the root/leaf and ilocal/iremote terminology.
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<br>
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I read the manual page on PetscSFGetGraph() (<a href="https://petsc.org/release/docs/manualpages/PetscSF/PetscSFGetGraph.html" id="LPlnk343018">https://petsc.org/release/docs/manualpages/PetscSF/PetscSFGetGraph.html</a>) and that gave me the impression that
I need to PetscSFBcast() the point IDs from foreign ranks to the local ones. <br>
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Is this correct?<br>
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<a target="_blank" id="LPImageAnchor149289" href="https://ieeexplore.ieee.org/document/9442258"><img id="LPThumbnailImageId149289" alt="" style="display: block;" width="160" height="160" src="https://ieeexplore.ieee.org/assets/img/ieee_logo_smedia_200X200.png"></a></div>
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<a target="_blank" id="LPUrlAnchor149289" href="https://ieeexplore.ieee.org/document/9442258" style="text-decoration: none; color: var(--themePrimary);">The PetscSF Scalable Communication Layer | IEEE Journals & Magazine | IEEE Xplore</a></div>
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PetscSF, the communication component of the Portable, Extensible Toolkit for Scientific Computation (PETSc), is designed to provide PETSc's communication infrastructure suitable for exascale computers that utilize GPUs and other accelerators. PetscSF provides
a simple application programming interface (API) for managing common communication patterns in scientific computations by using a star ...</div>
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ieeexplore.ieee.org</div>
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<span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">Sincerely:</span></p>
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<span style="margin: 0px; color: red; font-family: "Courier New", monospace; font-size: 14pt;"><b style=""><span style="font-family: "Courier New", monospace;">J.A. Ferrand</span></b></span><u><span style="margin: 0px; color: red; font-family: "Swis721 BlkCn BT", sans-serif; font-size: 12pt;"></span></u></p>
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<span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">Embry-Riddle Aeronautical University - Daytona Beach FL</span></p>
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<span style="font-family: "Times New Roman", Times, serif;"></span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">M.Sc.</span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">
Aerospace Engineering | May 2022</span></p>
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<span style="font-family: "Times New Roman", Times, serif;"></span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">B.Sc.</span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">
Aerospace Engineering</span></p>
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<span style="font-family: "Times New Roman", Times, serif;"></span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">B.Sc.</span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">
Computational Mathematics</span></p>
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Gamma Tau</span><span style="color: rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 12pt; display: inline !important; font-size-adjust: none; background-color: rgb(255, 255, 255);"> </span><br>
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<span style="margin: 0px; color: rgb(0, 0, 0); font-family: "Times New Roman", Times, serif; font-size: 12pt;">Tau Beta Pi</span></p>
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(386)-843-1829</span></p>
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<span style="font-family: "Times New Roman", Times, serif;"></span><u><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">Email(s):</span></u><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">
ferranj2@my.erau.edu</span></p>
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<span style="font-family: "Times New Roman", Times, serif;"></span><span style="margin: 0px; color: black; font-family: Courant; font-size: 12pt;"><span style="margin: 0px; font-family: "Times New Roman", Times, serif;">
</span></span><span style="margin: 0px; color: black; font-family: "Times New Roman", Times, serif; font-size: 12pt;">jesus.ferrand@gmail.com</span></p>
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