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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Hi all,</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">I'm starting to migrate my code to DMDAs to use DMPlex but I have troubles that neither the documentation nor google can answer.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">1) I want to to traverse the DAG associated to the DMPlex in the following way: assuming I have a DMPlex of dimension 2, I have a point representing a cell (2 dimensional) and I want to find all neighbouring 2-dim cells. A way to do this may be to GetCone and then follow the arrows in reverse in the DAG from height 2 to height 1. Any routine to do that? I looked at the DM documentation page but cannot find the proper one. I tried all the GetAdjacency routines but none of them seems to give the right implementation. I am thinking of something like GetCone or GetSupport, but from 2-dim cell to adjacent 2-dim cell.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">2) I've noticed that the numbering concerning the Height in the BFS search of the DMPlex section is a bit inconsistent. What I mean is that if want all the 2-dim cells of my DMPlex I should do:</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">DMPlexGetHeightStratum(dm, d, &pStart, &pEnd);</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">with d = 0, but if I'd like to call</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">DMPlexCreateSection</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">and create DOFs on the 2-dim cell, I have to do:</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">numDof[f*(dim+1)+d] = 2;</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">with d = 2.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Is there any reason behind that? I was trying with some mock example and fell into this trap a couple of times.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">3) This brings me to the following: I've noticed that the documentation is a bit "sparse", and I'd really like to contribute, especially improving the APIs documentation. I am not native speaker and new to all the DMPlex business but if you devs think this may be useful, I'll be glad to help.</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Would this be of any use to you?</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">4) I had problems loading meshes from Gmsh and, as far as I understood, it seems that is not PETSc preferred mesher (got problems with boundaries IS). PETSc seems to like this ExodusII format, any suggestion of a tool similar to Gmsh that creates ExodusII meshes?</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Sorry for the length and thanks in advance.</p>
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<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Best,</p>
<p style=" margin-top:0px; margin-bottom:0px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px; -qt-user-state:0;">Filippo</p></body></html>