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    <p>Dear petsc-users,</p>
    <p>    I am playing with DMPlexGetCellCoordinates and observing that
      it returns correct periodic coordinates for cells, but not for
      faces.</p>
    <p>More precisely, adding <br>
    </p>
    <p>    <font face="monospace">PetscCall(DMPlexGetHeightStratum(dm,
        1, &fStart, &fEnd));<br>
            for (f = fStart; f < fEnd; ++f) {<br>
              const PetscScalar *array;<br>
              PetscScalar       *x = NULL;<br>
              PetscInt           ndof;<br>
              PetscBool          isDG;<br>
        <br>
              PetscCall(DMPlexGetCellCoordinates(dm, f, &isDG,
        &ndof, &array, &x));<br>
              PetscCheck(ndof % cdim == 0, PETSC_COMM_SELF,
        PETSC_ERR_ARG_INCOMP, "ndof not divisible by cdim");<br>
              PetscCall(PetscPrintf(PETSC_COMM_SELF, "Face #%"
        PetscInt_FMT " coordinates\n", f - fStart));<br>
              for (PetscInt i = 0; i < ndof; i += cdim)
        PetscCall(PetscScalarView(cdim, &x[i],
        PETSC_VIEWER_STDOUT_SELF));<br>
              PetscCall(DMPlexRestoreCellCoordinates(dm, f, &isDG,
        &ndof, &array, &x));<br>
            }</font><br>
    </p>
    <p>to src/dm/impls/plex/tutorials/ex8.c, I get <font face="monospace"><br>
      </font></p>
    <p><font face="monospace">$ ./ex8 -dm_plex_dim 2 -petscspace_degree
        1 -dm_plex_simplex 0 -dm_plex_box_faces 3,2 -dm_plex_box_bd
        periodic,none -dm_view -view_coord <br>
        DM Object: box 1 MPI process<br>
          type: plex<br>
        box in 2 dimensions:<br>
          Number of 0-cells per rank: 9<br>
          Number of 1-cells per rank: 15<br>
          Number of 2-cells per rank: 6<br>
        Periodic mesh (PERIODIC, NONE) coordinates localized<br>
      </font></p>
    <p><font face="monospace">[...]</font></p>
    <p><font face="monospace">Element #2 coordinates<br>
         0:   6.6667e-01   0.0000e+00<br>
        <font color="#26a269"> 0:   1.0000e+00   0.0000e+00 
          <<<----- correct<br>
           0:   1.0000e+00   5.0000e-01</font><br>
         0:   6.6667e-01   5.0000e-01<br>
        [...]</font></p>
    <p><font face="monospace">Face #0 coordinates<br>
         0:   0.0000e+00   0.0000e+00<br>
         0:   3.3333e-01   0.0000e+00<br>
        Face #1 coordinates<br>
         0:   3.3333e-01   0.0000e+00<br>
         0:   6.6667e-01   0.0000e+00<br>
        Face #2 coordinates<br>
        <font color="#a51d2d"> 0:   6.6667e-01   0.0000e+00<br>
           0:   0.0000e+00   0.0000e+00  <<<---- should be
          (0.66,0.00) and (1.00,0.00)<br>
        </font></font></p>
    <p>Is there a way to recover correct periodic coordinates in the
      case of periodic DMPLex?</p>
    <p>Thanks in advance</p>
    <p>Matteo<br>
    </p>
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