xref: /petsc/src/dm/impls/plex/plexcreate.c (revision af0996ce37bc06907c37d8d91773840993d61e62)
1 #define PETSCDM_DLL
2 #include <petsc/private/dmpleximpl.h>    /*I   "petscdmplex.h"   I*/
3 #include <petscdmda.h>
4 #include <petscsf.h>
5 
6 #undef __FUNCT__
7 #define __FUNCT__ "DMPlexCreateDoublet"
8 /*@
9   DMPlexCreateDoublet - Creates a mesh of two cells of the specified type, optionally with later refinement.
10 
11   Collective on MPI_Comm
12 
13   Input Parameters:
14 + comm - The communicator for the DM object
15 . dim - The spatial dimension
16 . simplex - Flag for simplicial cells, otherwise they are tensor product cells
17 . interpolate - Flag to create intermediate mesh pieces (edges, faces)
18 . refinementUniform - Flag for uniform parallel refinement
19 - refinementLimit - A nonzero number indicates the largest admissible volume for a refined cell
20 
21   Output Parameter:
22 . dm  - The DM object
23 
24   Level: beginner
25 
26 .keywords: DM, create
27 .seealso: DMSetType(), DMCreate()
28 @*/
29 PetscErrorCode DMPlexCreateDoublet(MPI_Comm comm, PetscInt dim, PetscBool simplex, PetscBool interpolate, PetscBool refinementUniform, PetscReal refinementLimit, DM *newdm)
30 {
31   DM             dm;
32   PetscInt       p;
33   PetscMPIInt    rank;
34   PetscErrorCode ierr;
35 
36   PetscFunctionBegin;
37   ierr = DMCreate(comm, &dm);CHKERRQ(ierr);
38   ierr = DMSetType(dm, DMPLEX);CHKERRQ(ierr);
39   ierr = DMSetDimension(dm, dim);CHKERRQ(ierr);
40   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
41   switch (dim) {
42   case 2:
43     if (simplex) {ierr = PetscObjectSetName((PetscObject) dm, "triangular");CHKERRQ(ierr);}
44     else         {ierr = PetscObjectSetName((PetscObject) dm, "quadrilateral");CHKERRQ(ierr);}
45     break;
46   case 3:
47     if (simplex) {ierr = PetscObjectSetName((PetscObject) dm, "tetrahedral");CHKERRQ(ierr);}
48     else         {ierr = PetscObjectSetName((PetscObject) dm, "hexahedral");CHKERRQ(ierr);}
49     break;
50   default:
51     SETERRQ1(comm, PETSC_ERR_ARG_OUTOFRANGE, "Cannot make meshes for dimension %d", dim);
52   }
53   if (rank) {
54     PetscInt numPoints[2] = {0, 0};
55     ierr = DMPlexCreateFromDAG(dm, 1, numPoints, NULL, NULL, NULL, NULL);CHKERRQ(ierr);
56   } else {
57     switch (dim) {
58     case 2:
59       if (simplex) {
60         PetscInt    numPoints[2]        = {4, 2};
61         PetscInt    coneSize[6]         = {3, 3, 0, 0, 0, 0};
62         PetscInt    cones[6]            = {2, 3, 4,  5, 4, 3};
63         PetscInt    coneOrientations[6] = {0, 0, 0,  0, 0, 0};
64         PetscScalar vertexCoords[8]     = {-0.5, 0.5, 0.0, 0.0, 0.0, 1.0, 0.5, 0.5};
65         PetscInt    markerPoints[8]     = {2, 1, 3, 1, 4, 1, 5, 1};
66 
67         ierr = DMPlexCreateFromDAG(dm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
68         for (p = 0; p < 4; ++p) {ierr = DMPlexSetLabelValue(dm, "marker", markerPoints[p*2], markerPoints[p*2+1]);CHKERRQ(ierr);}
69       } else {
70         PetscInt    numPoints[2]        = {6, 2};
71         PetscInt    coneSize[8]         = {4, 4, 0, 0, 0, 0, 0, 0};
72         PetscInt    cones[8]            = {2, 3, 4, 5,  3, 6, 7, 4};
73         PetscInt    coneOrientations[8] = {0, 0, 0, 0,  0, 0, 0, 0};
74         PetscScalar vertexCoords[12]    = {-1.0, -0.5,  0.0, -0.5,  0.0, 0.5,  -1.0, 0.5,  1.0, -0.5,  1.0, 0.5};
75 
76         ierr = DMPlexCreateFromDAG(dm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
77       }
78       break;
79     case 3:
80       if (simplex) {
81         PetscInt    numPoints[2]        = {5, 2};
82         PetscInt    coneSize[7]         = {4, 4, 0, 0, 0, 0, 0};
83         PetscInt    cones[8]            = {4, 3, 5, 2,  5, 3, 4, 6};
84         PetscInt    coneOrientations[8] = {0, 0, 0, 0,  0, 0, 0, 0};
85         PetscScalar vertexCoords[15]    = {-1.0, 0.0, 0.0,  0.0, -1.0, 0.0,  0.0, 0.0, 1.0,  0.0, 1.0, 0.0,  1.0, 0.0, 0.0};
86         PetscInt    markerPoints[10]    = {2, 1, 3, 1, 4, 1, 5, 1, 6, 1};
87 
88         ierr = DMPlexCreateFromDAG(dm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
89         for (p = 0; p < 5; ++p) {ierr = DMPlexSetLabelValue(dm, "marker", markerPoints[p*2], markerPoints[p*2+1]);CHKERRQ(ierr);}
90       } else {
91         PetscInt    numPoints[2]         = {12, 2};
92         PetscInt    coneSize[14]         = {8, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
93         PetscInt    cones[16]            = {2, 3, 4, 5, 6, 7, 8, 9,  5, 4, 10, 11, 7, 12, 13, 8};
94         PetscInt    coneOrientations[16] = {0, 0, 0, 0, 0, 0, 0, 0,  0, 0,  0,  0, 0,  0,  0, 0};
95         PetscScalar vertexCoords[36]     = {-1.0, -0.5, -0.5,  -1.0,  0.5, -0.5,  0.0,  0.5, -0.5,   0.0, -0.5, -0.5,
96                                             -1.0, -0.5,  0.5,   0.0, -0.5,  0.5,  0.0,  0.5,  0.5,  -1.0,  0.5,  0.5,
97                                              1.0,  0.5, -0.5,   1.0, -0.5, -0.5,  1.0, -0.5,  0.5,   1.0,  0.5,  0.5};
98 
99         ierr = DMPlexCreateFromDAG(dm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
100       }
101       break;
102     default:
103       SETERRQ1(comm, PETSC_ERR_ARG_OUTOFRANGE, "Cannot make meshes for dimension %d", dim);
104     }
105   }
106   *newdm = dm;
107   if (refinementLimit > 0.0) {
108     DM rdm;
109     const char *name;
110 
111     ierr = DMPlexSetRefinementUniform(*newdm, PETSC_FALSE);CHKERRQ(ierr);
112     ierr = DMPlexSetRefinementLimit(*newdm, refinementLimit);CHKERRQ(ierr);
113     ierr = DMRefine(*newdm, comm, &rdm);CHKERRQ(ierr);
114     ierr = PetscObjectGetName((PetscObject) *newdm, &name);CHKERRQ(ierr);
115     ierr = PetscObjectSetName((PetscObject)    rdm,  name);CHKERRQ(ierr);
116     ierr = DMDestroy(newdm);CHKERRQ(ierr);
117     *newdm = rdm;
118   }
119   if (interpolate) {
120     DM idm = NULL;
121     const char *name;
122 
123     ierr = DMPlexInterpolate(*newdm, &idm);CHKERRQ(ierr);
124     ierr = PetscObjectGetName((PetscObject) *newdm, &name);CHKERRQ(ierr);
125     ierr = PetscObjectSetName((PetscObject)    idm,  name);CHKERRQ(ierr);
126     ierr = DMPlexCopyCoordinates(*newdm, idm);CHKERRQ(ierr);
127     ierr = DMPlexCopyLabels(*newdm, idm);CHKERRQ(ierr);
128     ierr = DMDestroy(newdm);CHKERRQ(ierr);
129     *newdm = idm;
130   }
131   {
132     DM refinedMesh     = NULL;
133     DM distributedMesh = NULL;
134 
135     /* Distribute mesh over processes */
136     ierr = DMPlexDistribute(*newdm, 0, NULL, &distributedMesh);CHKERRQ(ierr);
137     if (distributedMesh) {
138       ierr = DMDestroy(newdm);CHKERRQ(ierr);
139       *newdm = distributedMesh;
140     }
141     if (refinementUniform) {
142       ierr = DMPlexSetRefinementUniform(*newdm, refinementUniform);CHKERRQ(ierr);
143       ierr = DMRefine(*newdm, comm, &refinedMesh);CHKERRQ(ierr);
144       if (refinedMesh) {
145         ierr = DMDestroy(newdm);CHKERRQ(ierr);
146         *newdm = refinedMesh;
147       }
148     }
149   }
150   PetscFunctionReturn(0);
151 }
152 
153 #undef __FUNCT__
154 #define __FUNCT__ "DMPlexCreateSquareBoundary"
155 /*@
156   DMPlexCreateSquareBoundary - Creates a 1D mesh the is the boundary of a square lattice.
157 
158   Collective on MPI_Comm
159 
160   Input Parameters:
161 + comm  - The communicator for the DM object
162 . lower - The lower left corner coordinates
163 . upper - The upper right corner coordinates
164 - edges - The number of cells in each direction
165 
166   Output Parameter:
167 . dm  - The DM object
168 
169   Note: Here is the numbering returned for 2 cells in each direction:
170 $ 18--5-17--4--16
171 $  |     |     |
172 $  6    10     3
173 $  |     |     |
174 $ 19-11-20--9--15
175 $  |     |     |
176 $  7     8     2
177 $  |     |     |
178 $ 12--0-13--1--14
179 
180   Level: beginner
181 
182 .keywords: DM, create
183 .seealso: DMPlexCreateBoxMesh(), DMPlexCreateCubeBoundary(), DMSetType(), DMCreate()
184 @*/
185 PetscErrorCode DMPlexCreateSquareBoundary(DM dm, const PetscReal lower[], const PetscReal upper[], const PetscInt edges[])
186 {
187   PetscInt       numVertices    = (edges[0]+1)*(edges[1]+1);
188   PetscInt       numEdges       = edges[0]*(edges[1]+1) + (edges[0]+1)*edges[1];
189   PetscInt       markerTop      = 1;
190   PetscInt       markerBottom   = 1;
191   PetscInt       markerRight    = 1;
192   PetscInt       markerLeft     = 1;
193   PetscBool      markerSeparate = PETSC_FALSE;
194   Vec            coordinates;
195   PetscSection   coordSection;
196   PetscScalar    *coords;
197   PetscInt       coordSize;
198   PetscMPIInt    rank;
199   PetscInt       v, vx, vy;
200   PetscErrorCode ierr;
201 
202   PetscFunctionBegin;
203   ierr = PetscOptionsGetBool(((PetscObject) dm)->prefix, "-dm_plex_separate_marker", &markerSeparate, NULL);CHKERRQ(ierr);
204   if (markerSeparate) {
205     markerTop    = 1;
206     markerBottom = 0;
207     markerRight  = 0;
208     markerLeft   = 0;
209   }
210   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank);CHKERRQ(ierr);
211   if (!rank) {
212     PetscInt e, ex, ey;
213 
214     ierr = DMPlexSetChart(dm, 0, numEdges+numVertices);CHKERRQ(ierr);
215     for (e = 0; e < numEdges; ++e) {
216       ierr = DMPlexSetConeSize(dm, e, 2);CHKERRQ(ierr);
217     }
218     ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
219     for (vx = 0; vx <= edges[0]; vx++) {
220       for (ey = 0; ey < edges[1]; ey++) {
221         PetscInt edge   = vx*edges[1] + ey + edges[0]*(edges[1]+1);
222         PetscInt vertex = ey*(edges[0]+1) + vx + numEdges;
223         PetscInt cone[2];
224 
225         cone[0] = vertex; cone[1] = vertex+edges[0]+1;
226         ierr    = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
227         if (vx == edges[0]) {
228           ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerRight);CHKERRQ(ierr);
229           ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerRight);CHKERRQ(ierr);
230           if (ey == edges[1]-1) {
231             ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerRight);CHKERRQ(ierr);
232           }
233         } else if (vx == 0) {
234           ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerLeft);CHKERRQ(ierr);
235           ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerLeft);CHKERRQ(ierr);
236           if (ey == edges[1]-1) {
237             ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerLeft);CHKERRQ(ierr);
238           }
239         }
240       }
241     }
242     for (vy = 0; vy <= edges[1]; vy++) {
243       for (ex = 0; ex < edges[0]; ex++) {
244         PetscInt edge   = vy*edges[0]     + ex;
245         PetscInt vertex = vy*(edges[0]+1) + ex + numEdges;
246         PetscInt cone[2];
247 
248         cone[0] = vertex; cone[1] = vertex+1;
249         ierr    = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
250         if (vy == edges[1]) {
251           ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerTop);CHKERRQ(ierr);
252           ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerTop);CHKERRQ(ierr);
253           if (ex == edges[0]-1) {
254             ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerTop);CHKERRQ(ierr);
255           }
256         } else if (vy == 0) {
257           ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerBottom);CHKERRQ(ierr);
258           ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerBottom);CHKERRQ(ierr);
259           if (ex == edges[0]-1) {
260             ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerBottom);CHKERRQ(ierr);
261           }
262         }
263       }
264     }
265   }
266   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
267   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
268   /* Build coordinates */
269   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
270   ierr = PetscSectionSetChart(coordSection, numEdges, numEdges + numVertices);CHKERRQ(ierr);
271   for (v = numEdges; v < numEdges+numVertices; ++v) {
272     ierr = PetscSectionSetDof(coordSection, v, 2);CHKERRQ(ierr);
273   }
274   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
275   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
276   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
277   ierr = VecSetBlockSize(coordinates, 2);CHKERRQ(ierr);
278   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
279   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
280   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
281   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
282   for (vy = 0; vy <= edges[1]; ++vy) {
283     for (vx = 0; vx <= edges[0]; ++vx) {
284       coords[(vy*(edges[0]+1)+vx)*2+0] = lower[0] + ((upper[0] - lower[0])/edges[0])*vx;
285       coords[(vy*(edges[0]+1)+vx)*2+1] = lower[1] + ((upper[1] - lower[1])/edges[1])*vy;
286     }
287   }
288   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
289   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
290   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
291   PetscFunctionReturn(0);
292 }
293 
294 #undef __FUNCT__
295 #define __FUNCT__ "DMPlexCreateCubeBoundary"
296 /*@
297   DMPlexCreateCubeBoundary - Creates a 2D mesh the is the boundary of a cubic lattice.
298 
299   Collective on MPI_Comm
300 
301   Input Parameters:
302 + comm  - The communicator for the DM object
303 . lower - The lower left front corner coordinates
304 . upper - The upper right back corner coordinates
305 - edges - The number of cells in each direction
306 
307   Output Parameter:
308 . dm  - The DM object
309 
310   Level: beginner
311 
312 .keywords: DM, create
313 .seealso: DMPlexCreateBoxMesh(), DMPlexCreateSquareBoundary(), DMSetType(), DMCreate()
314 @*/
315 PetscErrorCode DMPlexCreateCubeBoundary(DM dm, const PetscReal lower[], const PetscReal upper[], const PetscInt faces[])
316 {
317   PetscInt       vertices[3], numVertices;
318   PetscInt       numFaces    = 2*faces[0]*faces[1] + 2*faces[1]*faces[2] + 2*faces[0]*faces[2];
319   Vec            coordinates;
320   PetscSection   coordSection;
321   PetscScalar    *coords;
322   PetscInt       coordSize;
323   PetscMPIInt    rank;
324   PetscInt       v, vx, vy, vz;
325   PetscInt       voffset, iface=0, cone[4];
326   PetscErrorCode ierr;
327 
328   PetscFunctionBegin;
329   if ((faces[0] < 1) || (faces[1] < 1) || (faces[2] < 1)) SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_SUP, "Must have at least 1 face per side");
330   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank);CHKERRQ(ierr);
331   vertices[0] = faces[0]+1; vertices[1] = faces[1]+1; vertices[2] = faces[2]+1;
332   numVertices = vertices[0]*vertices[1]*vertices[2];
333   if (!rank) {
334     PetscInt f;
335 
336     ierr = DMPlexSetChart(dm, 0, numFaces+numVertices);CHKERRQ(ierr);
337     for (f = 0; f < numFaces; ++f) {
338       ierr = DMPlexSetConeSize(dm, f, 4);CHKERRQ(ierr);
339     }
340     ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
341     for (v = 0; v < numFaces+numVertices; ++v) {
342       ierr = DMPlexSetLabelValue(dm, "marker", v, 1);CHKERRQ(ierr);
343     }
344 
345     /* Side 0 (Top) */
346     for (vy = 0; vy < faces[1]; vy++) {
347       for (vx = 0; vx < faces[0]; vx++) {
348         voffset = numFaces + vertices[0]*vertices[1]*(vertices[2]-1) + vy*vertices[0] + vx;
349         cone[0] = voffset; cone[1] = voffset+1; cone[2] = voffset+vertices[0]+1; cone[3] = voffset+vertices[0];
350         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
351         iface++;
352       }
353     }
354 
355     /* Side 1 (Bottom) */
356     for (vy = 0; vy < faces[1]; vy++) {
357       for (vx = 0; vx < faces[0]; vx++) {
358         voffset = numFaces + vy*(faces[0]+1) + vx;
359         cone[0] = voffset+1; cone[1] = voffset; cone[2] = voffset+vertices[0]; cone[3] = voffset+vertices[0]+1;
360         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
361         iface++;
362       }
363     }
364 
365     /* Side 2 (Front) */
366     for (vz = 0; vz < faces[2]; vz++) {
367       for (vx = 0; vx < faces[0]; vx++) {
368         voffset = numFaces + vz*vertices[0]*vertices[1] + vx;
369         cone[0] = voffset; cone[1] = voffset+1; cone[2] = voffset+vertices[0]*vertices[1]+1; cone[3] = voffset+vertices[0]*vertices[1];
370         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
371         iface++;
372       }
373     }
374 
375     /* Side 3 (Back) */
376     for (vz = 0; vz < faces[2]; vz++) {
377       for (vx = 0; vx < faces[0]; vx++) {
378         voffset = numFaces + vz*vertices[0]*vertices[1] + vertices[0]*(vertices[1]-1) + vx;
379         cone[0] = voffset+vertices[0]*vertices[1]; cone[1] = voffset+vertices[0]*vertices[1]+1;
380         cone[2] = voffset+1; cone[3] = voffset;
381         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
382         iface++;
383       }
384     }
385 
386     /* Side 4 (Left) */
387     for (vz = 0; vz < faces[2]; vz++) {
388       for (vy = 0; vy < faces[1]; vy++) {
389         voffset = numFaces + vz*vertices[0]*vertices[1] + vy*vertices[0];
390         cone[0] = voffset; cone[1] = voffset+vertices[0]*vertices[1];
391         cone[2] = voffset+vertices[0]*vertices[1]+vertices[0]; cone[3] = voffset+vertices[0];
392         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
393         iface++;
394       }
395     }
396 
397     /* Side 5 (Right) */
398     for (vz = 0; vz < faces[2]; vz++) {
399       for (vy = 0; vy < faces[1]; vy++) {
400         voffset = numFaces + vz*vertices[0]*vertices[1] + vy*vertices[0] + vx;
401         cone[0] = voffset+vertices[0]*vertices[1]; cone[1] = voffset;
402         cone[2] = voffset+vertices[0]; cone[3] = voffset+vertices[0]*vertices[1]+vertices[0];
403         ierr    = DMPlexSetCone(dm, iface, cone);CHKERRQ(ierr);
404         iface++;
405       }
406     }
407   }
408   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
409   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
410   /* Build coordinates */
411   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
412   ierr = PetscSectionSetChart(coordSection, numFaces, numFaces + numVertices);CHKERRQ(ierr);
413   for (v = numFaces; v < numFaces+numVertices; ++v) {
414     ierr = PetscSectionSetDof(coordSection, v, 3);CHKERRQ(ierr);
415   }
416   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
417   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
418   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
419   ierr = VecSetBlockSize(coordinates, 3);CHKERRQ(ierr);
420   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
421   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
422   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
423   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
424   for (vz = 0; vz <= faces[2]; ++vz) {
425     for (vy = 0; vy <= faces[1]; ++vy) {
426       for (vx = 0; vx <= faces[0]; ++vx) {
427         coords[((vz*(faces[1]+1)+vy)*(faces[0]+1)+vx)*3+0] = lower[0] + ((upper[0] - lower[0])/faces[0])*vx;
428         coords[((vz*(faces[1]+1)+vy)*(faces[0]+1)+vx)*3+1] = lower[1] + ((upper[1] - lower[1])/faces[1])*vy;
429         coords[((vz*(faces[1]+1)+vy)*(faces[0]+1)+vx)*3+2] = lower[2] + ((upper[2] - lower[2])/faces[2])*vz;
430       }
431     }
432   }
433   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
434   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
435   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
436   PetscFunctionReturn(0);
437 }
438 
439 #undef __FUNCT__
440 #define __FUNCT__ "DMPlexCreateCubeMesh_Internal"
441 static PetscErrorCode DMPlexCreateCubeMesh_Internal(DM dm, const PetscReal lower[], const PetscReal upper[], const PetscInt edges[], DMBoundaryType bdX, DMBoundaryType bdY, DMBoundaryType bdZ)
442 {
443   PetscInt       markerTop      = 1, faceMarkerTop      = 1;
444   PetscInt       markerBottom   = 1, faceMarkerBottom   = 1;
445   PetscInt       markerFront    = 1, faceMarkerFront    = 1;
446   PetscInt       markerBack     = 1, faceMarkerBack     = 1;
447   PetscInt       markerRight    = 1, faceMarkerRight    = 1;
448   PetscInt       markerLeft     = 1, faceMarkerLeft     = 1;
449   PetscInt       dim;
450   PetscBool      markerSeparate = PETSC_FALSE;
451   PetscMPIInt    rank;
452   PetscErrorCode ierr;
453 
454   PetscFunctionBegin;
455   ierr = DMGetDimension(dm,&dim);CHKERRQ(ierr);
456   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)dm), &rank);CHKERRQ(ierr);
457   switch (dim) {
458   case 2:
459     faceMarkerTop    = 3;
460     faceMarkerBottom = 1;
461     faceMarkerRight  = 2;
462     faceMarkerLeft   = 4;
463     break;
464   case 3:
465     faceMarkerBottom = 1;
466     faceMarkerTop    = 2;
467     faceMarkerFront  = 3;
468     faceMarkerBack   = 4;
469     faceMarkerRight  = 5;
470     faceMarkerLeft   = 6;
471     break;
472   default:
473     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Dimension %d not supported",dim);
474     break;
475   }
476   ierr = PetscOptionsGetBool(((PetscObject) dm)->prefix, "-dm_plex_separate_marker", &markerSeparate, NULL);CHKERRQ(ierr);
477   if (markerSeparate) {
478     markerBottom = faceMarkerBottom;
479     markerTop    = faceMarkerTop;
480     markerFront  = faceMarkerFront;
481     markerBack   = faceMarkerBack;
482     markerRight  = faceMarkerRight;
483     markerLeft   = faceMarkerLeft;
484   }
485   {
486     const PetscInt numXEdges    = !rank ? edges[0]   : 0;
487     const PetscInt numYEdges    = !rank ? edges[1]   : 0;
488     const PetscInt numZEdges    = !rank ? edges[2]   : 0;
489     const PetscInt numXVertices = !rank ? (bdX == DM_BOUNDARY_PERIODIC || bdX == DM_BOUNDARY_TWIST ? edges[0] : edges[0]+1) : 0;
490     const PetscInt numYVertices = !rank ? (bdY == DM_BOUNDARY_PERIODIC || bdY == DM_BOUNDARY_TWIST ? edges[1] : edges[1]+1) : 0;
491     const PetscInt numZVertices = !rank ? (bdZ == DM_BOUNDARY_PERIODIC || bdY == DM_BOUNDARY_TWIST ? edges[2] : edges[2]+1) : 0;
492     const PetscInt numCells     = numXEdges*numYEdges*numZEdges;
493     const PetscInt numXFaces    = numYEdges*numZEdges;
494     const PetscInt numYFaces    = numXEdges*numZEdges;
495     const PetscInt numZFaces    = numXEdges*numYEdges;
496     const PetscInt numTotXFaces = numXVertices*numXFaces;
497     const PetscInt numTotYFaces = numYVertices*numYFaces;
498     const PetscInt numTotZFaces = numZVertices*numZFaces;
499     const PetscInt numFaces     = numTotXFaces + numTotYFaces + numTotZFaces;
500     const PetscInt numTotXEdges = numXEdges*numYVertices*numZVertices;
501     const PetscInt numTotYEdges = numYEdges*numXVertices*numZVertices;
502     const PetscInt numTotZEdges = numZEdges*numXVertices*numYVertices;
503     const PetscInt numVertices  = numXVertices*numYVertices*numZVertices;
504     const PetscInt numEdges     = numTotXEdges + numTotYEdges + numTotZEdges;
505     const PetscInt firstVertex  = (dim == 2) ? numFaces : numCells;
506     const PetscInt firstXFace   = (dim == 2) ? 0 : numCells + numVertices;
507     const PetscInt firstYFace   = firstXFace + numTotXFaces;
508     const PetscInt firstZFace   = firstYFace + numTotYFaces;
509     const PetscInt firstXEdge   = numCells + numFaces + numVertices;
510     const PetscInt firstYEdge   = firstXEdge + numTotXEdges;
511     const PetscInt firstZEdge   = firstYEdge + numTotYEdges;
512     Vec            coordinates;
513     PetscSection   coordSection;
514     PetscScalar   *coords;
515     PetscInt       coordSize;
516     PetscInt       v, vx, vy, vz;
517     PetscInt       c, f, fx, fy, fz, e, ex, ey, ez;
518 
519     ierr = DMPlexSetChart(dm, 0, numCells+numFaces+numEdges+numVertices);CHKERRQ(ierr);
520     for (c = 0; c < numCells; c++) {
521       ierr = DMPlexSetConeSize(dm, c, 6);CHKERRQ(ierr);
522     }
523     for (f = firstXFace; f < firstXFace+numFaces; ++f) {
524       ierr = DMPlexSetConeSize(dm, f, 4);CHKERRQ(ierr);
525     }
526     for (e = firstXEdge; e < firstXEdge+numEdges; ++e) {
527       ierr = DMPlexSetConeSize(dm, e, 2);CHKERRQ(ierr);
528     }
529     ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
530     /* Build cells */
531     for (fz = 0; fz < numZEdges; ++fz) {
532       for (fy = 0; fy < numYEdges; ++fy) {
533         for (fx = 0; fx < numXEdges; ++fx) {
534           PetscInt cell    = (fz*numYEdges + fy)*numXEdges + fx;
535           PetscInt faceB   = firstZFace + (fy*numXEdges+fx)*numZVertices +   fz;
536           PetscInt faceT   = firstZFace + (fy*numXEdges+fx)*numZVertices + ((fz+1)%numZVertices);
537           PetscInt faceF   = firstYFace + (fz*numXEdges+fx)*numYVertices +   fy;
538           PetscInt faceK   = firstYFace + (fz*numXEdges+fx)*numYVertices + ((fy+1)%numYVertices);
539           PetscInt faceL   = firstXFace + (fz*numYEdges+fy)*numXVertices +   fx;
540           PetscInt faceR   = firstXFace + (fz*numYEdges+fy)*numXVertices + ((fx+1)%numXVertices);
541                             /* B,  T,  F,  K,  R,  L */
542           PetscInt ornt[8] = {-4,  0,  0, -1,  0, -4}; /* ??? */
543           PetscInt cone[8];
544 
545           /* no boundary twisting in 3D */
546           cone[0] = faceB; cone[1] = faceT; cone[2] = faceF; cone[3] = faceK; cone[4] = faceR; cone[5] = faceL;
547           ierr    = DMPlexSetCone(dm, cell, cone);CHKERRQ(ierr);
548           ierr    = DMPlexSetConeOrientation(dm, cell, ornt);CHKERRQ(ierr);
549         }
550       }
551     }
552     /* Build x faces */
553     for (fz = 0; fz < numZEdges; ++fz) {
554       for (fy = 0; fy < numYEdges; ++fy) {
555         for (fx = 0; fx < numXVertices; ++fx) {
556           PetscInt face    = firstXFace + (fz*numYEdges+fy)*numXVertices + fx;
557           PetscInt edgeL   = firstZEdge + (  fy*                 numXVertices+fx)*numZEdges + fz;
558           PetscInt edgeR   = firstZEdge + (((fy+1)%numYVertices)*numXVertices+fx)*numZEdges + fz;
559           PetscInt edgeB   = firstYEdge + (  fz*                 numXVertices+fx)*numYEdges + fy;
560           PetscInt edgeT   = firstYEdge + (((fz+1)%numZVertices)*numXVertices+fx)*numYEdges + fy;
561           PetscInt ornt[4] = {0, 0, -2, -2};
562           PetscInt cone[4];
563 
564           if (dim == 3) {
565             /* markers */
566             if (bdX != DM_BOUNDARY_PERIODIC) {
567               if (fx == numXVertices-1) {
568                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerRight);CHKERRQ(ierr);
569                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerRight);CHKERRQ(ierr);
570               }
571               else if (fx == 0) {
572                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerLeft);CHKERRQ(ierr);
573                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerLeft);CHKERRQ(ierr);
574               }
575             }
576           }
577           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
578           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
579           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
580         }
581       }
582     }
583     /* Build y faces */
584     for (fz = 0; fz < numZEdges; ++fz) {
585       for (fx = 0; fx < numYEdges; ++fx) {
586         for (fy = 0; fy < numYVertices; ++fy) {
587           PetscInt face    = firstYFace + (fz*numXEdges+fx)*numYVertices + fy;
588           PetscInt edgeL   = firstZEdge + (fy*numXVertices+  fx                 )*numZEdges + fz;
589           PetscInt edgeR   = firstZEdge + (fy*numXVertices+((fx+1)%numXVertices))*numZEdges + fz;
590           PetscInt edgeB   = firstXEdge + (  fz                 *numYVertices+fy)*numXEdges + fx;
591           PetscInt edgeT   = firstXEdge + (((fz+1)%numZVertices)*numYVertices+fy)*numXEdges + fx;
592           PetscInt ornt[4] = {0, 0, -2, -2};
593           PetscInt cone[4];
594 
595           if (dim == 3) {
596             /* markers */
597             if (bdY != DM_BOUNDARY_PERIODIC) {
598               if (fy == numYVertices-1) {
599                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerBack);CHKERRQ(ierr);
600                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerBack);CHKERRQ(ierr);
601               }
602               else if (fy == 0) {
603                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerFront);CHKERRQ(ierr);
604                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerFront);CHKERRQ(ierr);
605               }
606             }
607           }
608           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
609           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
610           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
611         }
612       }
613     }
614     /* Build z faces */
615     for (fy = 0; fy < numYEdges; ++fy) {
616       for (fx = 0; fx < numXEdges; ++fx) {
617         for (fz = 0; fz < numZVertices; fz++) {
618           PetscInt face    = firstZFace + (fy*numXEdges+fx)*numZVertices + fz;
619           PetscInt edgeL   = firstYEdge + (fz*numXVertices+  fx                 )*numYEdges + fy;
620           PetscInt edgeR   = firstYEdge + (fz*numXVertices+((fx+1)%numXVertices))*numYEdges + fy;
621           PetscInt edgeB   = firstXEdge + (fz*numYVertices+  fy                 )*numXEdges + fx;
622           PetscInt edgeT   = firstXEdge + (fz*numYVertices+((fy+1)%numYVertices))*numXEdges + fx;
623           PetscInt ornt[4] = {0, 0, -2, -2};
624           PetscInt cone[4];
625 
626           if (dim == 2) {
627             if (bdX == DM_BOUNDARY_TWIST && fx == numXEdges-1) {edgeR += numYEdges-1-2*fy; ornt[1] = -2;}
628             if (bdY == DM_BOUNDARY_TWIST && fy == numYEdges-1) {edgeT += numXEdges-1-2*fx; ornt[2] =  0;}
629           }
630           else {
631             /* markers */
632             if (bdZ != DM_BOUNDARY_PERIODIC) {
633               if (fz == numZVertices-1) {
634                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerTop);CHKERRQ(ierr);
635                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerTop);CHKERRQ(ierr);
636               }
637               else if (fz == 0) {
638                 ierr = DMPlexSetLabelValue(dm, "Face Sets", face, faceMarkerBottom);CHKERRQ(ierr);
639                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerBottom);CHKERRQ(ierr);
640               }
641             }
642           }
643           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
644           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
645           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
646         }
647       }
648     }
649     /* Build Z edges*/
650     for (vy = 0; vy < numYVertices; vy++) {
651       for (vx = 0; vx < numXVertices; vx++) {
652         for (ez = 0; ez < numZEdges; ez++) {
653           const PetscInt edge    = firstZEdge  + (vy*numXVertices+vx)*numZEdges + ez;
654           const PetscInt vertexB = firstVertex + (  ez                 *numYVertices+vy)*numXVertices + vx;
655           const PetscInt vertexT = firstVertex + (((ez+1)%numZVertices)*numYVertices+vy)*numXVertices + vx;
656           PetscInt       cone[2];
657 
658           if (dim == 3) {
659             if (bdX != DM_BOUNDARY_PERIODIC) {
660               if (vx == numXVertices-1) {
661                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerRight);CHKERRQ(ierr);
662               }
663               else if (vx == 0) {
664                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerLeft);CHKERRQ(ierr);
665               }
666             }
667             if (bdY != DM_BOUNDARY_PERIODIC) {
668               if (vy == numYVertices-1) {
669                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBack);CHKERRQ(ierr);
670               }
671               else if (vy == 0) {
672                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerFront);CHKERRQ(ierr);
673               }
674             }
675           }
676           cone[0] = vertexB; cone[1] = vertexT;
677           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
678         }
679       }
680     }
681     /* Build Y edges*/
682     for (vz = 0; vz < numZVertices; vz++) {
683       for (vx = 0; vx < numXVertices; vx++) {
684         for (ey = 0; ey < numYEdges; ey++) {
685           const PetscInt nextv   = (dim == 2 && bdY == DM_BOUNDARY_TWIST && ey == numYEdges-1) ? (numXVertices-vx-1) : (vz*numYVertices+((ey+1)%numYVertices))*numXVertices + vx;
686           const PetscInt edge    = firstYEdge  + (vz*numXVertices+vx)*numYEdges + ey;
687           const PetscInt vertexF = firstVertex + (vz*numYVertices+ey)*numXVertices + vx;
688           const PetscInt vertexK = firstVertex + nextv;
689           PetscInt       cone[2];
690 
691           cone[0] = vertexF; cone[1] = vertexK;
692           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
693           if (dim == 2) {
694             if ((bdX != DM_BOUNDARY_PERIODIC) && (bdX != DM_BOUNDARY_TWIST)) {
695               if (vx == numXVertices-1) {
696                 ierr = DMPlexSetLabelValue(dm, "Face Sets", edge, faceMarkerRight);CHKERRQ(ierr);
697                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerRight);CHKERRQ(ierr);
698                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerRight);CHKERRQ(ierr);
699                 if (ey == numYEdges-1) {
700                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerRight);CHKERRQ(ierr);
701                 }
702               }
703               else if (vx == 0) {
704                 ierr = DMPlexSetLabelValue(dm, "Face Sets", edge, faceMarkerLeft);CHKERRQ(ierr);
705                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerLeft);CHKERRQ(ierr);
706                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerLeft);CHKERRQ(ierr);
707                 if (ey == numYEdges-1) {
708                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerLeft);CHKERRQ(ierr);
709                 }
710               }
711             }
712           }
713           else {
714             if (bdX != DM_BOUNDARY_PERIODIC) {
715               if (vx == numXVertices-1) {
716                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerRight);CHKERRQ(ierr);
717               }
718               else if (vx == 0) {
719                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerLeft);CHKERRQ(ierr);
720               }
721             }
722             if (bdZ != DM_BOUNDARY_PERIODIC) {
723               if (vz == numZVertices-1) {
724                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerTop);CHKERRQ(ierr);
725               }
726               else if (vz == 0) {
727                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBottom);CHKERRQ(ierr);
728               }
729             }
730           }
731         }
732       }
733     }
734     /* Build X edges*/
735     for (vz = 0; vz < numZVertices; vz++) {
736       for (vy = 0; vy < numYVertices; vy++) {
737         for (ex = 0; ex < numXEdges; ex++) {
738           const PetscInt nextv   = (dim == 2 && bdX == DM_BOUNDARY_TWIST && ex == numXEdges-1) ? (numYVertices-vy-1)*numXVertices : (vz*numYVertices+vy)*numXVertices + (ex+1)%numXVertices;
739           const PetscInt edge    = firstXEdge  + (vz*numYVertices+vy)*numXEdges + ex;
740           const PetscInt vertexL = firstVertex + (vz*numYVertices+vy)*numXVertices + ex;
741           const PetscInt vertexR = firstVertex + nextv;
742           PetscInt       cone[2];
743 
744           cone[0] = vertexL; cone[1] = vertexR;
745           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
746           if (dim == 2) {
747             if ((bdY != DM_BOUNDARY_PERIODIC) && (bdY != DM_BOUNDARY_TWIST)) {
748               if (vy == numYVertices-1) {
749                 ierr = DMPlexSetLabelValue(dm, "Face Sets", edge, faceMarkerTop);CHKERRQ(ierr);
750                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerTop);CHKERRQ(ierr);
751                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerTop);CHKERRQ(ierr);
752                 if (ex == numXEdges-1) {
753                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerTop);CHKERRQ(ierr);
754                 }
755               }
756               else if (vy == 0) {
757                 ierr = DMPlexSetLabelValue(dm, "Face Sets", edge, faceMarkerBottom);CHKERRQ(ierr);
758                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerBottom);CHKERRQ(ierr);
759                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerBottom);CHKERRQ(ierr);
760                 if (ex == numXEdges-1) {
761                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerBottom);CHKERRQ(ierr);
762                 }
763               }
764             }
765           }
766           else {
767             if (bdY != DM_BOUNDARY_PERIODIC) {
768               if (vy == numYVertices-1) {
769                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBack);CHKERRQ(ierr);
770               }
771               else if (vy == 0) {
772                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerFront);CHKERRQ(ierr);
773               }
774             }
775             if (bdZ != DM_BOUNDARY_PERIODIC) {
776               if (vz == numZVertices-1) {
777                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerTop);CHKERRQ(ierr);
778               }
779               else if (vz == 0) {
780                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBottom);CHKERRQ(ierr);
781               }
782             }
783           }
784         }
785       }
786     }
787     ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
788     ierr = DMPlexStratify(dm);CHKERRQ(ierr);
789     /* Build coordinates */
790     ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
791     ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
792     ierr = PetscSectionSetFieldComponents(coordSection, 0, dim);CHKERRQ(ierr);
793     ierr = PetscSectionSetChart(coordSection, firstVertex, firstVertex+numVertices);CHKERRQ(ierr);
794     for (v = firstVertex; v < firstVertex+numVertices; ++v) {
795       ierr = PetscSectionSetDof(coordSection, v, dim);CHKERRQ(ierr);
796       ierr = PetscSectionSetFieldDof(coordSection, v, 0, dim);CHKERRQ(ierr);
797     }
798     ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
799     ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
800     ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
801     ierr = VecSetBlockSize(coordinates, dim);CHKERRQ(ierr);
802     ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
803     ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
804     ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
805     ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
806     for (vz = 0; vz < numZVertices; ++vz) {
807       for (vy = 0; vy < numYVertices; ++vy) {
808         for (vx = 0; vx < numXVertices; ++vx) {
809           coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+0] = lower[0] + ((upper[0] - lower[0])/numXEdges)*vx;
810           coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+1] = lower[1] + ((upper[1] - lower[1])/numYEdges)*vy;
811           if (dim == 3) {
812             coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+2] = lower[2] + ((upper[2] - lower[2])/numZEdges)*vz;
813           }
814         }
815       }
816     }
817     ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
818     ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
819     ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
820   }
821   PetscFunctionReturn(0);
822 }
823 
824 #undef __FUNCT__
825 #define __FUNCT__ "DMPlexCreateSquareMesh"
826 /*@
827   DMPlexCreateSquareMesh - Creates a 2D mesh for a square lattice.
828 
829   Collective on MPI_Comm
830 
831   Input Parameters:
832 + comm  - The communicator for the DM object
833 . lower - The lower left corner coordinates
834 . upper - The upper right corner coordinates
835 . edges - The number of cells in each direction
836 . bdX   - The boundary type for the X direction
837 - bdY   - The boundary type for the Y direction
838 
839   Output Parameter:
840 . dm  - The DM object
841 
842   Note: Here is the numbering returned for 2 cells in each direction:
843 $ 22--8-23--9--24
844 $  |     |     |
845 $ 13  2 14  3  15
846 $  |     |     |
847 $ 19--6-20--7--21
848 $  |     |     |
849 $ 10  0 11  1 12
850 $  |     |     |
851 $ 16--4-17--5--18
852 
853   Level: beginner
854 
855 .keywords: DM, create
856 .seealso: DMPlexCreateBoxMesh(), DMPlexCreateSquareBoundary(), DMPlexCreateCubeBoundary(), DMSetType(), DMCreate()
857 @*/
858 PetscErrorCode DMPlexCreateSquareMesh(DM dm, const PetscReal lower[], const PetscReal upper[], const PetscInt edges[], DMBoundaryType bdX, DMBoundaryType bdY)
859 {
860   PetscReal      lower3[3], upper3[3];
861   PetscInt       edges3[3];
862   PetscErrorCode ierr;
863 
864   PetscFunctionBegin;
865   lower3[0] = lower[0]; lower3[1] = lower[1]; lower3[2] = 0.;
866   upper3[0] = upper[0]; upper3[1] = upper[1]; upper3[2] = 0.;
867   edges3[0] = edges[0]; edges3[1] = edges[1]; edges3[2] = 0;
868   ierr = DMPlexCreateCubeMesh_Internal(dm, lower3, upper3, edges3, bdX, bdY, DM_BOUNDARY_NONE);CHKERRQ(ierr);
869   PetscFunctionReturn(0);
870 }
871 
872 #undef __FUNCT__
873 #define __FUNCT__ "DMPlexCreateBoxMesh"
874 /*@
875   DMPlexCreateBoxMesh - Creates a mesh on the tensor product of unit intervals (box) using simplices.
876 
877   Collective on MPI_Comm
878 
879   Input Parameters:
880 + comm - The communicator for the DM object
881 . dim - The spatial dimension
882 - interpolate - Flag to create intermediate mesh pieces (edges, faces)
883 
884   Output Parameter:
885 . dm  - The DM object
886 
887   Level: beginner
888 
889 .keywords: DM, create
890 .seealso: DMPlexCreateHexBoxMesh(), DMSetType(), DMCreate()
891 @*/
892 PetscErrorCode DMPlexCreateBoxMesh(MPI_Comm comm, PetscInt dim, PetscBool interpolate, DM *dm)
893 {
894   DM             boundary;
895   PetscErrorCode ierr;
896 
897   PetscFunctionBegin;
898   PetscValidPointer(dm, 4);
899   ierr = DMCreate(comm, &boundary);CHKERRQ(ierr);
900   PetscValidLogicalCollectiveInt(boundary,dim,2);
901   ierr = DMSetType(boundary, DMPLEX);CHKERRQ(ierr);
902   ierr = DMSetDimension(boundary, dim-1);CHKERRQ(ierr);
903   switch (dim) {
904   case 2:
905   {
906     PetscReal lower[2] = {0.0, 0.0};
907     PetscReal upper[2] = {1.0, 1.0};
908     PetscInt  edges[2] = {2, 2};
909 
910     ierr = DMPlexCreateSquareBoundary(boundary, lower, upper, edges);CHKERRQ(ierr);
911     break;
912   }
913   case 3:
914   {
915     PetscReal lower[3] = {0.0, 0.0, 0.0};
916     PetscReal upper[3] = {1.0, 1.0, 1.0};
917     PetscInt  faces[3] = {1, 1, 1};
918 
919     ierr = DMPlexCreateCubeBoundary(boundary, lower, upper, faces);CHKERRQ(ierr);
920     break;
921   }
922   default:
923     SETERRQ1(comm, PETSC_ERR_SUP, "Dimension not supported: %d", dim);
924   }
925   ierr = DMPlexGenerate(boundary, NULL, interpolate, dm);CHKERRQ(ierr);
926   ierr = DMDestroy(&boundary);CHKERRQ(ierr);
927   PetscFunctionReturn(0);
928 }
929 
930 #undef __FUNCT__
931 #define __FUNCT__ "DMPlexCreateHexBoxMesh"
932 /*@
933   DMPlexCreateHexBoxMesh - Creates a mesh on the tensor product of unit intervals (box) using hexahedra.
934 
935   Collective on MPI_Comm
936 
937   Input Parameters:
938 + comm  - The communicator for the DM object
939 . dim   - The spatial dimension
940 . periodicX - The boundary type for the X direction
941 . periodicY - The boundary type for the Y direction
942 . periodicZ - The boundary type for the Z direction
943 - cells - The number of cells in each direction
944 
945   Output Parameter:
946 . dm  - The DM object
947 
948   Level: beginner
949 
950 .keywords: DM, create
951 .seealso: DMPlexCreateBoxMesh(), DMSetType(), DMCreate()
952 @*/
953 PetscErrorCode DMPlexCreateHexBoxMesh(MPI_Comm comm, PetscInt dim, const PetscInt cells[], DMBoundaryType periodicX, DMBoundaryType periodicY, DMBoundaryType periodicZ, DM *dm)
954 {
955   PetscErrorCode ierr;
956 
957   PetscFunctionBegin;
958   PetscValidPointer(dm, 4);
959   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
960   PetscValidLogicalCollectiveInt(*dm,dim,2);
961   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
962   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
963   switch (dim) {
964   case 2:
965   {
966     PetscReal lower[2] = {0.0, 0.0};
967     PetscReal upper[2] = {1.0, 1.0};
968 
969     ierr = DMPlexCreateSquareMesh(*dm, lower, upper, cells, periodicX, periodicY);CHKERRQ(ierr);
970     break;
971   }
972   case 3:
973   {
974     PetscReal lower[3] = {0.0, 0.0, 0.0};
975     PetscReal upper[3] = {1.0, 1.0, 1.0};
976 
977     ierr = DMPlexCreateCubeMesh_Internal(*dm, lower, upper, cells, periodicX, periodicY, periodicZ);CHKERRQ(ierr);
978     break;
979   }
980   default:
981     SETERRQ1(comm, PETSC_ERR_SUP, "Dimension not supported: %d", dim);
982   }
983   PetscFunctionReturn(0);
984 }
985 
986 /* External function declarations here */
987 extern PetscErrorCode DMCreateInterpolation_Plex(DM dmCoarse, DM dmFine, Mat *interpolation, Vec *scaling);
988 extern PetscErrorCode DMCreateInjection_Plex(DM dmCoarse, DM dmFine, Mat *mat);
989 extern PetscErrorCode DMCreateDefaultSection_Plex(DM dm);
990 extern PetscErrorCode DMCreateDefaultConstraints_Plex(DM dm);
991 extern PetscErrorCode DMCreateMatrix_Plex(DM dm,  Mat *J);
992 extern PetscErrorCode DMCreateCoordinateDM_Plex(DM dm, DM *cdm);
993 extern PetscErrorCode DMRefine_Plex(DM dm, MPI_Comm comm, DM *dmRefined);
994 extern PetscErrorCode DMCoarsen_Plex(DM dm, MPI_Comm comm, DM *dmCoarsened);
995 extern PetscErrorCode DMRefineHierarchy_Plex(DM dm, PetscInt nlevels, DM dmRefined[]);
996 extern PetscErrorCode DMClone_Plex(DM dm, DM *newdm);
997 extern PetscErrorCode DMSetUp_Plex(DM dm);
998 extern PetscErrorCode DMDestroy_Plex(DM dm);
999 extern PetscErrorCode DMView_Plex(DM dm, PetscViewer viewer);
1000 extern PetscErrorCode DMLoad_Plex(DM dm, PetscViewer viewer);
1001 extern PetscErrorCode DMCreateSubDM_Plex(DM dm, PetscInt numFields, PetscInt fields[], IS *is, DM *subdm);
1002 extern PetscErrorCode DMLocatePoints_Plex(DM dm, Vec v, IS *cellIS);
1003 
1004 #undef __FUNCT__
1005 #define __FUNCT__ "DMPlexReplace_Static"
1006 /* Replace dm with the contents of dmNew
1007    - Share the DM_Plex structure
1008    - Share the coordinates
1009    - Share the SF
1010 */
1011 static PetscErrorCode DMPlexReplace_Static(DM dm, DM dmNew)
1012 {
1013   PetscSF          sf;
1014   DM               coordDM;
1015   Vec              coords;
1016   const PetscReal *maxCell, *L;
1017   const DMBoundaryType *bd;
1018   PetscErrorCode   ierr;
1019 
1020   PetscFunctionBegin;
1021   ierr = DMGetPointSF(dmNew, &sf);CHKERRQ(ierr);
1022   ierr = DMSetPointSF(dm, sf);CHKERRQ(ierr);
1023   ierr = DMGetCoordinateDM(dmNew, &coordDM);CHKERRQ(ierr);
1024   ierr = DMGetCoordinatesLocal(dmNew, &coords);CHKERRQ(ierr);
1025   ierr = DMSetCoordinateDM(dm, coordDM);CHKERRQ(ierr);
1026   ierr = DMSetCoordinatesLocal(dm, coords);CHKERRQ(ierr);
1027   ierr = DMGetPeriodicity(dm, &maxCell, &L, &bd);CHKERRQ(ierr);
1028   if (L) {ierr = DMSetPeriodicity(dmNew, maxCell, L, bd);CHKERRQ(ierr);}
1029   ierr = DMDestroy_Plex(dm);CHKERRQ(ierr);
1030   dm->data = dmNew->data;
1031   ((DM_Plex *) dmNew->data)->refct++;
1032   PetscFunctionReturn(0);
1033 }
1034 
1035 #undef __FUNCT__
1036 #define __FUNCT__ "DMPlexSwap_Static"
1037 /* Swap dm with the contents of dmNew
1038    - Swap the DM_Plex structure
1039    - Swap the coordinates
1040 */
1041 static PetscErrorCode DMPlexSwap_Static(DM dmA, DM dmB)
1042 {
1043   DM             coordDMA, coordDMB;
1044   Vec            coordsA,  coordsB;
1045   void          *tmp;
1046   PetscErrorCode ierr;
1047 
1048   PetscFunctionBegin;
1049   ierr = DMGetCoordinateDM(dmA, &coordDMA);CHKERRQ(ierr);
1050   ierr = DMGetCoordinateDM(dmB, &coordDMB);CHKERRQ(ierr);
1051   ierr = PetscObjectReference((PetscObject) coordDMA);CHKERRQ(ierr);
1052   ierr = DMSetCoordinateDM(dmA, coordDMB);CHKERRQ(ierr);
1053   ierr = DMSetCoordinateDM(dmB, coordDMA);CHKERRQ(ierr);
1054   ierr = PetscObjectDereference((PetscObject) coordDMA);CHKERRQ(ierr);
1055 
1056   ierr = DMGetCoordinatesLocal(dmA, &coordsA);CHKERRQ(ierr);
1057   ierr = DMGetCoordinatesLocal(dmB, &coordsB);CHKERRQ(ierr);
1058   ierr = PetscObjectReference((PetscObject) coordsA);CHKERRQ(ierr);
1059   ierr = DMSetCoordinatesLocal(dmA, coordsB);CHKERRQ(ierr);
1060   ierr = DMSetCoordinatesLocal(dmB, coordsA);CHKERRQ(ierr);
1061   ierr = PetscObjectDereference((PetscObject) coordsA);CHKERRQ(ierr);
1062   tmp       = dmA->data;
1063   dmA->data = dmB->data;
1064   dmB->data = tmp;
1065   PetscFunctionReturn(0);
1066 }
1067 
1068 #undef __FUNCT__
1069 #define __FUNCT__ "DMSetFromOptions_NonRefinement_Plex"
1070 PetscErrorCode  DMSetFromOptions_NonRefinement_Plex(PetscOptions *PetscOptionsObject,DM dm)
1071 {
1072   DM_Plex       *mesh = (DM_Plex*) dm->data;
1073   DMBoundary     b;
1074   PetscErrorCode ierr;
1075 
1076   PetscFunctionBegin;
1077   /* Handle boundary conditions */
1078   ierr = PetscOptionsBegin(PetscObjectComm((PetscObject) dm), NULL, "Boundary condition options", "");CHKERRQ(ierr);
1079   for (b = mesh->boundary; b; b = b->next) {
1080     char      optname[1024];
1081     PetscInt  ids[1024], len = 1024, i;
1082     PetscBool flg;
1083 
1084     ierr = PetscSNPrintf(optname, sizeof(optname), "-bc_%s", b->name);CHKERRQ(ierr);
1085     ierr = PetscMemzero(ids, sizeof(ids));CHKERRQ(ierr);
1086     ierr = PetscOptionsIntArray(optname, "List of boundary IDs", "", ids, &len, &flg);CHKERRQ(ierr);
1087     if (flg) {
1088       DMLabel label;
1089 
1090       ierr = DMPlexGetLabel(dm, b->labelname, &label);CHKERRQ(ierr);
1091       for (i = 0; i < len; ++i) {
1092         PetscBool has;
1093 
1094         ierr = DMLabelHasValue(label, ids[i], &has);CHKERRQ(ierr);
1095         if (!has) SETERRQ2(PetscObjectComm((PetscObject) dm), PETSC_ERR_ARG_WRONG, "Boundary id %D is not present in the label %s", ids[i], b->name);
1096       }
1097       b->numids = len;
1098       ierr = PetscFree(b->ids);CHKERRQ(ierr);
1099       ierr = PetscMalloc1(len, &b->ids);CHKERRQ(ierr);
1100       ierr = PetscMemcpy(b->ids, ids, len*sizeof(PetscInt));CHKERRQ(ierr);
1101     }
1102   }
1103   ierr = PetscOptionsEnd();CHKERRQ(ierr);
1104   /* Handle viewing */
1105   ierr = PetscOptionsBool("-dm_plex_print_set_values", "Output all set values info", "DMView", PETSC_FALSE, &mesh->printSetValues, NULL);CHKERRQ(ierr);
1106   ierr = PetscOptionsInt("-dm_plex_print_fem", "Debug output level all fem computations", "DMView", 0, &mesh->printFEM, NULL);CHKERRQ(ierr);
1107   ierr = PetscOptionsReal("-dm_plex_print_tol", "Tolerance for FEM output", "DMView", mesh->printTol, &mesh->printTol, NULL);CHKERRQ(ierr);
1108   /* Projection behavior */
1109   ierr = PetscOptionsInt("-dm_plex_max_projection_height", "Maxmimum mesh point height used to project locally", "DMPlexSetMaxProjectionHeight", 0, &mesh->maxProjectionHeight, NULL);CHKERRQ(ierr);
1110   PetscFunctionReturn(0);
1111 }
1112 
1113 #undef __FUNCT__
1114 #define __FUNCT__ "DMSetFromOptions_Plex"
1115 PetscErrorCode  DMSetFromOptions_Plex(PetscOptions *PetscOptionsObject,DM dm)
1116 {
1117   PetscInt       refine = 0, r;
1118   PetscBool      isHierarchy;
1119   PetscErrorCode ierr;
1120 
1121   PetscFunctionBegin;
1122   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1123   ierr = PetscOptionsHead(PetscOptionsObject,"DMPlex Options");CHKERRQ(ierr);
1124   /* Handle DMPlex refinement */
1125   ierr = PetscOptionsInt("-dm_refine", "The number of uniform refinements", "DMCreate", refine, &refine, NULL);CHKERRQ(ierr);
1126   ierr = PetscOptionsInt("-dm_refine_hierarchy", "The number of uniform refinements", "DMCreate", refine, &refine, &isHierarchy);CHKERRQ(ierr);
1127   if (refine) {ierr = DMPlexSetRefinementUniform(dm, PETSC_TRUE);CHKERRQ(ierr);}
1128   if (refine && isHierarchy) {
1129     DM *dms;
1130 
1131     ierr = PetscMalloc1(refine,&dms);CHKERRQ(ierr);
1132     ierr = DMRefineHierarchy(dm, refine, dms);CHKERRQ(ierr);
1133     /* Total hack since we do not pass in a pointer */
1134     ierr = DMPlexSwap_Static(dm, dms[refine-1]);CHKERRQ(ierr);
1135     if (refine == 1) {
1136       ierr = DMPlexSetCoarseDM(dm, dms[0]);CHKERRQ(ierr);
1137     } else {
1138       ierr = DMPlexSetCoarseDM(dm, dms[refine-2]);CHKERRQ(ierr);
1139       ierr = DMPlexSetCoarseDM(dms[0], dms[refine-1]);CHKERRQ(ierr);
1140     }
1141     /* Free DMs */
1142     for (r = 0; r < refine; ++r) {
1143       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject,dm);CHKERRQ(ierr);
1144       ierr = DMDestroy(&dms[r]);CHKERRQ(ierr);
1145     }
1146     ierr = PetscFree(dms);CHKERRQ(ierr);
1147   } else {
1148     for (r = 0; r < refine; ++r) {
1149       DM refinedMesh;
1150 
1151       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject,dm);CHKERRQ(ierr);
1152       ierr = DMRefine(dm, PetscObjectComm((PetscObject) dm), &refinedMesh);CHKERRQ(ierr);
1153       /* Total hack since we do not pass in a pointer */
1154       ierr = DMPlexReplace_Static(dm, refinedMesh);CHKERRQ(ierr);
1155       ierr = DMDestroy(&refinedMesh);CHKERRQ(ierr);
1156     }
1157   }
1158   ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject,dm);CHKERRQ(ierr);
1159   ierr = PetscOptionsTail();CHKERRQ(ierr);
1160   PetscFunctionReturn(0);
1161 }
1162 
1163 #undef __FUNCT__
1164 #define __FUNCT__ "DMCreateGlobalVector_Plex"
1165 static PetscErrorCode DMCreateGlobalVector_Plex(DM dm,Vec *vec)
1166 {
1167   PetscErrorCode ierr;
1168 
1169   PetscFunctionBegin;
1170   ierr = DMCreateGlobalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1171   /* ierr = VecSetOperation(*vec, VECOP_DUPLICATE, (void(*)(void)) VecDuplicate_MPI_DM);CHKERRQ(ierr); */
1172   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex);CHKERRQ(ierr);
1173   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex);CHKERRQ(ierr);
1174   PetscFunctionReturn(0);
1175 }
1176 
1177 #undef __FUNCT__
1178 #define __FUNCT__ "DMCreateLocalVector_Plex"
1179 static PetscErrorCode DMCreateLocalVector_Plex(DM dm,Vec *vec)
1180 {
1181   PetscErrorCode ierr;
1182 
1183   PetscFunctionBegin;
1184   ierr = DMCreateLocalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1185   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex_Local);CHKERRQ(ierr);
1186   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex_Local);CHKERRQ(ierr);
1187   PetscFunctionReturn(0);
1188 }
1189 
1190 #undef __FUNCT__
1191 #define __FUNCT__ "DMGetDimPoints_Plex"
1192 static PetscErrorCode DMGetDimPoints_Plex(DM dm, PetscInt dim, PetscInt *pStart, PetscInt *pEnd)
1193 {
1194   PetscInt       depth, d;
1195   PetscErrorCode ierr;
1196 
1197   PetscFunctionBegin;
1198   ierr = DMPlexGetDepth(dm, &depth);CHKERRQ(ierr);
1199   if (depth == 1) {
1200     ierr = DMGetDimension(dm, &d);CHKERRQ(ierr);
1201     if (dim == 0)      {ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);}
1202     else if (dim == d) {ierr = DMPlexGetDepthStratum(dm, 1, pStart, pEnd);CHKERRQ(ierr);}
1203     else               {*pStart = 0; *pEnd = 0;}
1204   } else {
1205     ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);
1206   }
1207   PetscFunctionReturn(0);
1208 }
1209 
1210 #undef __FUNCT__
1211 #define __FUNCT__ "DMInitialize_Plex"
1212 PetscErrorCode DMInitialize_Plex(DM dm)
1213 {
1214   PetscFunctionBegin;
1215   dm->ops->view                            = DMView_Plex;
1216   dm->ops->load                            = DMLoad_Plex;
1217   dm->ops->setfromoptions                  = DMSetFromOptions_Plex;
1218   dm->ops->clone                           = DMClone_Plex;
1219   dm->ops->setup                           = DMSetUp_Plex;
1220   dm->ops->createdefaultsection            = DMCreateDefaultSection_Plex;
1221   dm->ops->createdefaultconstraints        = DMCreateDefaultConstraints_Plex;
1222   dm->ops->createglobalvector              = DMCreateGlobalVector_Plex;
1223   dm->ops->createlocalvector               = DMCreateLocalVector_Plex;
1224   dm->ops->getlocaltoglobalmapping         = NULL;
1225   dm->ops->createfieldis                   = NULL;
1226   dm->ops->createcoordinatedm              = DMCreateCoordinateDM_Plex;
1227   dm->ops->getcoloring                     = NULL;
1228   dm->ops->creatematrix                    = DMCreateMatrix_Plex;
1229   dm->ops->createinterpolation             = DMCreateInterpolation_Plex;
1230   dm->ops->getaggregates                   = NULL;
1231   dm->ops->getinjection                    = DMCreateInjection_Plex;
1232   dm->ops->refine                          = DMRefine_Plex;
1233   dm->ops->coarsen                         = DMCoarsen_Plex;
1234   dm->ops->refinehierarchy                 = DMRefineHierarchy_Plex;
1235   dm->ops->coarsenhierarchy                = NULL;
1236   dm->ops->globaltolocalbegin              = NULL;
1237   dm->ops->globaltolocalend                = NULL;
1238   dm->ops->localtoglobalbegin              = NULL;
1239   dm->ops->localtoglobalend                = NULL;
1240   dm->ops->destroy                         = DMDestroy_Plex;
1241   dm->ops->createsubdm                     = DMCreateSubDM_Plex;
1242   dm->ops->getdimpoints                    = DMGetDimPoints_Plex;
1243   dm->ops->locatepoints                    = DMLocatePoints_Plex;
1244   PetscFunctionReturn(0);
1245 }
1246 
1247 #undef __FUNCT__
1248 #define __FUNCT__ "DMClone_Plex"
1249 PetscErrorCode DMClone_Plex(DM dm, DM *newdm)
1250 {
1251   DM_Plex        *mesh = (DM_Plex *) dm->data;
1252   PetscErrorCode ierr;
1253 
1254   PetscFunctionBegin;
1255   mesh->refct++;
1256   (*newdm)->data = mesh;
1257   ierr = PetscObjectChangeTypeName((PetscObject) *newdm, DMPLEX);CHKERRQ(ierr);
1258   ierr = DMInitialize_Plex(*newdm);CHKERRQ(ierr);
1259   PetscFunctionReturn(0);
1260 }
1261 
1262 /*MC
1263   DMPLEX = "plex" - A DM object that encapsulates an unstructured mesh, or CW Complex, which can be expressed using a Hasse Diagram.
1264                     In the local representation, Vecs contain all unknowns in the interior and shared boundary. This is
1265                     specified by a PetscSection object. Ownership in the global representation is determined by
1266                     ownership of the underlying DMPlex points. This is specified by another PetscSection object.
1267 
1268   Level: intermediate
1269 
1270 .seealso: DMType, DMPlexCreate(), DMCreate(), DMSetType()
1271 M*/
1272 
1273 #undef __FUNCT__
1274 #define __FUNCT__ "DMCreate_Plex"
1275 PETSC_EXTERN PetscErrorCode DMCreate_Plex(DM dm)
1276 {
1277   DM_Plex        *mesh;
1278   PetscInt       unit, d;
1279   PetscErrorCode ierr;
1280 
1281   PetscFunctionBegin;
1282   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1283   ierr     = PetscNewLog(dm,&mesh);CHKERRQ(ierr);
1284   dm->dim  = 0;
1285   dm->data = mesh;
1286 
1287   mesh->refct             = 1;
1288   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->coneSection);CHKERRQ(ierr);
1289   mesh->maxConeSize       = 0;
1290   mesh->cones             = NULL;
1291   mesh->coneOrientations  = NULL;
1292   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->supportSection);CHKERRQ(ierr);
1293   mesh->maxSupportSize    = 0;
1294   mesh->supports          = NULL;
1295   mesh->refinementUniform = PETSC_TRUE;
1296   mesh->refinementLimit   = -1.0;
1297 
1298   mesh->facesTmp = NULL;
1299 
1300   mesh->tetgenOpts   = NULL;
1301   mesh->triangleOpts = NULL;
1302   ierr = PetscPartitionerCreate(PetscObjectComm((PetscObject)dm), &mesh->partitioner);CHKERRQ(ierr);
1303   ierr = PetscPartitionerSetTypeFromOptions_Internal(mesh->partitioner);CHKERRQ(ierr);
1304 
1305   mesh->subpointMap = NULL;
1306 
1307   for (unit = 0; unit < NUM_PETSC_UNITS; ++unit) mesh->scale[unit] = 1.0;
1308 
1309   mesh->labels              = NULL;
1310   mesh->depthLabel          = NULL;
1311   mesh->globalVertexNumbers = NULL;
1312   mesh->globalCellNumbers   = NULL;
1313   mesh->anchorSection       = NULL;
1314   mesh->anchorIS            = NULL;
1315   mesh->createanchors       = NULL;
1316   mesh->computeanchormatrix = NULL;
1317   mesh->parentSection       = NULL;
1318   mesh->parents             = NULL;
1319   mesh->childIDs            = NULL;
1320   mesh->childSection        = NULL;
1321   mesh->children            = NULL;
1322   mesh->referenceTree       = NULL;
1323   mesh->getchildsymmetry    = NULL;
1324   for (d = 0; d < 8; ++d) mesh->hybridPointMax[d] = PETSC_DETERMINE;
1325   mesh->vtkCellHeight       = 0;
1326   mesh->useCone             = PETSC_FALSE;
1327   mesh->useClosure          = PETSC_TRUE;
1328   mesh->useAnchors          = PETSC_FALSE;
1329 
1330   mesh->maxProjectionHeight = 0;
1331 
1332   mesh->printSetValues = PETSC_FALSE;
1333   mesh->printFEM       = 0;
1334   mesh->printTol       = 1.0e-10;
1335 
1336   ierr = DMInitialize_Plex(dm);CHKERRQ(ierr);
1337   PetscFunctionReturn(0);
1338 }
1339 
1340 #undef __FUNCT__
1341 #define __FUNCT__ "DMPlexCreate"
1342 /*@
1343   DMPlexCreate - Creates a DMPlex object, which encapsulates an unstructured mesh, or CW complex, which can be expressed using a Hasse Diagram.
1344 
1345   Collective on MPI_Comm
1346 
1347   Input Parameter:
1348 . comm - The communicator for the DMPlex object
1349 
1350   Output Parameter:
1351 . mesh  - The DMPlex object
1352 
1353   Level: beginner
1354 
1355 .keywords: DMPlex, create
1356 @*/
1357 PetscErrorCode DMPlexCreate(MPI_Comm comm, DM *mesh)
1358 {
1359   PetscErrorCode ierr;
1360 
1361   PetscFunctionBegin;
1362   PetscValidPointer(mesh,2);
1363   ierr = DMCreate(comm, mesh);CHKERRQ(ierr);
1364   ierr = DMSetType(*mesh, DMPLEX);CHKERRQ(ierr);
1365   PetscFunctionReturn(0);
1366 }
1367 
1368 #undef __FUNCT__
1369 #define __FUNCT__ "DMPlexBuildFromCellList_Private"
1370 /*
1371   This takes as input the common mesh generator output, a list of the vertices for each cell
1372 */
1373 PetscErrorCode DMPlexBuildFromCellList_Private(DM dm, PetscInt numCells, PetscInt numVertices, PetscInt numCorners, const int cells[])
1374 {
1375   PetscInt      *cone, c, p;
1376   PetscErrorCode ierr;
1377 
1378   PetscFunctionBegin;
1379   ierr = DMPlexSetChart(dm, 0, numCells+numVertices);CHKERRQ(ierr);
1380   for (c = 0; c < numCells; ++c) {
1381     ierr = DMPlexSetConeSize(dm, c, numCorners);CHKERRQ(ierr);
1382   }
1383   ierr = DMSetUp(dm);CHKERRQ(ierr);
1384   ierr = DMGetWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1385   for (c = 0; c < numCells; ++c) {
1386     for (p = 0; p < numCorners; ++p) {
1387       cone[p] = cells[c*numCorners+p]+numCells;
1388     }
1389     ierr = DMPlexSetCone(dm, c, cone);CHKERRQ(ierr);
1390   }
1391   ierr = DMRestoreWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1392   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1393   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1394   PetscFunctionReturn(0);
1395 }
1396 
1397 #undef __FUNCT__
1398 #define __FUNCT__ "DMPlexBuildCoordinates_Private"
1399 /*
1400   This takes as input the coordinates for each vertex
1401 */
1402 PetscErrorCode DMPlexBuildCoordinates_Private(DM dm, PetscInt spaceDim, PetscInt numCells, PetscInt numVertices, const double vertexCoords[])
1403 {
1404   PetscSection   coordSection;
1405   Vec            coordinates;
1406   PetscScalar   *coords;
1407   PetscInt       coordSize, v, d;
1408   PetscErrorCode ierr;
1409 
1410   PetscFunctionBegin;
1411   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1412   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1413   ierr = PetscSectionSetFieldComponents(coordSection, 0, spaceDim);CHKERRQ(ierr);
1414   ierr = PetscSectionSetChart(coordSection, numCells, numCells + numVertices);CHKERRQ(ierr);
1415   for (v = numCells; v < numCells+numVertices; ++v) {
1416     ierr = PetscSectionSetDof(coordSection, v, spaceDim);CHKERRQ(ierr);
1417     ierr = PetscSectionSetFieldDof(coordSection, v, 0, spaceDim);CHKERRQ(ierr);
1418   }
1419   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1420   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1421   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1422   ierr = VecSetBlockSize(coordinates, spaceDim);CHKERRQ(ierr);
1423   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1424   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1425   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1426   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1427   for (v = 0; v < numVertices; ++v) {
1428     for (d = 0; d < spaceDim; ++d) {
1429       coords[v*spaceDim+d] = vertexCoords[v*spaceDim+d];
1430     }
1431   }
1432   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1433   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1434   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1435   PetscFunctionReturn(0);
1436 }
1437 
1438 #undef __FUNCT__
1439 #define __FUNCT__ "DMPlexCreateFromCellList"
1440 /*@C
1441   DMPlexCreateFromCellList - This takes as input common mesh generator output, a list of the vertices for each cell, and produces a DM
1442 
1443   Input Parameters:
1444 + comm - The communicator
1445 . dim - The topological dimension of the mesh
1446 . numCells - The number of cells
1447 . numVertices - The number of vertices
1448 . numCorners - The number of vertices for each cell
1449 . interpolate - Flag indicating that intermediate mesh entities (faces, edges) should be created automatically
1450 . cells - An array of numCells*numCorners numbers, the vertices for each cell
1451 . spaceDim - The spatial dimension used for coordinates
1452 - vertexCoords - An array of numVertices*spaceDim numbers, the coordinates of each vertex
1453 
1454   Output Parameter:
1455 . dm - The DM
1456 
1457   Note: Two triangles sharing a face
1458 $
1459 $        2
1460 $      / | \
1461 $     /  |  \
1462 $    /   |   \
1463 $   0  0 | 1  3
1464 $    \   |   /
1465 $     \  |  /
1466 $      \ | /
1467 $        1
1468 would have input
1469 $  numCells = 2, numVertices = 4
1470 $  cells = [0 1 2  1 3 2]
1471 $
1472 which would result in the DMPlex
1473 $
1474 $        4
1475 $      / | \
1476 $     /  |  \
1477 $    /   |   \
1478 $   2  0 | 1  5
1479 $    \   |   /
1480 $     \  |  /
1481 $      \ | /
1482 $        3
1483 
1484   Level: beginner
1485 
1486 .seealso: DMPlexCreateFromDAG(), DMPlexCreate()
1487 @*/
1488 PetscErrorCode DMPlexCreateFromCellList(MPI_Comm comm, PetscInt dim, PetscInt numCells, PetscInt numVertices, PetscInt numCorners, PetscBool interpolate, const int cells[], PetscInt spaceDim, const double vertexCoords[], DM *dm)
1489 {
1490   PetscErrorCode ierr;
1491 
1492   PetscFunctionBegin;
1493   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
1494   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
1495   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
1496   ierr = DMPlexBuildFromCellList_Private(*dm, numCells, numVertices, numCorners, cells);CHKERRQ(ierr);
1497   if (interpolate) {
1498     DM idm = NULL;
1499 
1500     ierr = DMPlexInterpolate(*dm, &idm);CHKERRQ(ierr);
1501     ierr = DMDestroy(dm);CHKERRQ(ierr);
1502     *dm  = idm;
1503   }
1504   ierr = DMPlexBuildCoordinates_Private(*dm, spaceDim, numCells, numVertices, vertexCoords);CHKERRQ(ierr);
1505   PetscFunctionReturn(0);
1506 }
1507 
1508 #undef __FUNCT__
1509 #define __FUNCT__ "DMPlexCreateFromDAG"
1510 /*@
1511   DMPlexCreateFromDAG - This takes as input the adjacency-list representation of the Directed Acyclic Graph (Hasse Diagram) encoding a mesh, and produces a DM
1512 
1513   Input Parameters:
1514 + dm - The empty DM object, usually from DMCreate() and DMSetDimension()
1515 . depth - The depth of the DAG
1516 . numPoints - The number of points at each depth
1517 . coneSize - The cone size of each point
1518 . cones - The concatenation of the cone points for each point, the cone list must be oriented correctly for each point
1519 . coneOrientations - The orientation of each cone point
1520 - vertexCoords - An array of numVertices*dim numbers, the coordinates of each vertex
1521 
1522   Output Parameter:
1523 . dm - The DM
1524 
1525   Note: Two triangles sharing a face would have input
1526 $  depth = 1, numPoints = [4 2], coneSize = [3 3 0 0 0 0]
1527 $  cones = [2 3 4  3 5 4], coneOrientations = [0 0 0  0 0 0]
1528 $ vertexCoords = [-1.0 0.0  0.0 -1.0  0.0 1.0  1.0 0.0]
1529 $
1530 which would result in the DMPlex
1531 $
1532 $        4
1533 $      / | \
1534 $     /  |  \
1535 $    /   |   \
1536 $   2  0 | 1  5
1537 $    \   |   /
1538 $     \  |  /
1539 $      \ | /
1540 $        3
1541 $
1542 $ Notice that all points are numbered consecutively, unlikely DMPlexCreateFromCellList()
1543 
1544   Level: advanced
1545 
1546 .seealso: DMPlexCreateFromCellList(), DMPlexCreate()
1547 @*/
1548 PetscErrorCode DMPlexCreateFromDAG(DM dm, PetscInt depth, const PetscInt numPoints[], const PetscInt coneSize[], const PetscInt cones[], const PetscInt coneOrientations[], const PetscScalar vertexCoords[])
1549 {
1550   Vec            coordinates;
1551   PetscSection   coordSection;
1552   PetscScalar    *coords;
1553   PetscInt       coordSize, firstVertex = -1, pStart = 0, pEnd = 0, p, v, dim, dimEmbed, d, off;
1554   PetscErrorCode ierr;
1555 
1556   PetscFunctionBegin;
1557   ierr = DMGetDimension(dm, &dim);CHKERRQ(ierr);
1558   ierr = DMGetCoordinateDim(dm, &dimEmbed);CHKERRQ(ierr);
1559   if (dimEmbed < dim) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Embedding dimension %d cannot be less than intrinsic dimension %d",dimEmbed,dim);
1560   for (d = 0; d <= depth; ++d) pEnd += numPoints[d];
1561   ierr = DMPlexSetChart(dm, pStart, pEnd);CHKERRQ(ierr);
1562   for (p = pStart; p < pEnd; ++p) {
1563     ierr = DMPlexSetConeSize(dm, p, coneSize[p-pStart]);CHKERRQ(ierr);
1564     if (firstVertex < 0 && !coneSize[p - pStart]) {
1565       firstVertex = p - pStart;
1566     }
1567   }
1568   if (firstVertex < 0 && numPoints[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Expected %d vertices but could not find any", numPoints[0]);
1569   ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
1570   for (p = pStart, off = 0; p < pEnd; off += coneSize[p-pStart], ++p) {
1571     ierr = DMPlexSetCone(dm, p, &cones[off]);CHKERRQ(ierr);
1572     ierr = DMPlexSetConeOrientation(dm, p, &coneOrientations[off]);CHKERRQ(ierr);
1573   }
1574   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1575   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1576   /* Build coordinates */
1577   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1578   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1579   ierr = PetscSectionSetFieldComponents(coordSection, 0, dimEmbed);CHKERRQ(ierr);
1580   ierr = PetscSectionSetChart(coordSection, firstVertex, firstVertex+numPoints[0]);CHKERRQ(ierr);
1581   for (v = firstVertex; v < firstVertex+numPoints[0]; ++v) {
1582     ierr = PetscSectionSetDof(coordSection, v, dimEmbed);CHKERRQ(ierr);
1583     ierr = PetscSectionSetFieldDof(coordSection, v, 0, dimEmbed);CHKERRQ(ierr);
1584   }
1585   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1586   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1587   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1588   ierr = VecSetBlockSize(coordinates, dimEmbed);CHKERRQ(ierr);
1589   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1590   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1591   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1592   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1593   for (v = 0; v < numPoints[0]; ++v) {
1594     PetscInt off;
1595 
1596     ierr = PetscSectionGetOffset(coordSection, v+firstVertex, &off);CHKERRQ(ierr);
1597     for (d = 0; d < dimEmbed; ++d) {
1598       coords[off+d] = vertexCoords[v*dimEmbed+d];
1599     }
1600   }
1601   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1602   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1603   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1604   PetscFunctionReturn(0);
1605 }
1606 
1607 #undef __FUNCT__
1608 #define __FUNCT__ "DMPlexCreateFromFile"
1609 /*@C
1610   DMPlexCreateFromFile - This takes a filename and produces a DM
1611 
1612   Input Parameters:
1613 + comm - The communicator
1614 . filename - A file name
1615 - interpolate - Flag to create intermediate mesh pieces (edges, faces)
1616 
1617   Output Parameter:
1618 . dm - The DM
1619 
1620   Level: beginner
1621 
1622 .seealso: DMPlexCreateFromDAG(), DMPlexCreateFromCellList(), DMPlexCreate()
1623 @*/
1624 PetscErrorCode DMPlexCreateFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
1625 {
1626   const char    *extGmsh   = ".msh";
1627   const char    *extCGNS   = ".cgns";
1628   const char    *extExodus = ".exo";
1629   const char    *extFluent = ".cas";
1630   size_t         len;
1631   PetscBool      isGmsh, isCGNS, isExodus, isFluent;
1632   PetscMPIInt    rank;
1633   PetscErrorCode ierr;
1634 
1635   PetscFunctionBegin;
1636   PetscValidPointer(filename, 2);
1637   PetscValidPointer(dm, 4);
1638   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
1639   ierr = PetscStrlen(filename, &len);CHKERRQ(ierr);
1640   if (!len) SETERRQ(comm, PETSC_ERR_ARG_WRONG, "Filename must be a valid path");
1641   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extGmsh,   4, &isGmsh);CHKERRQ(ierr);
1642   ierr = PetscStrncmp(&filename[PetscMax(0,len-5)], extCGNS,   5, &isCGNS);CHKERRQ(ierr);
1643   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extExodus, 4, &isExodus);CHKERRQ(ierr);
1644   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extFluent, 4, &isFluent);CHKERRQ(ierr);
1645   if (isGmsh) {
1646     ierr = DMPlexCreateGmshFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1647   } else if (isCGNS) {
1648     ierr = DMPlexCreateCGNSFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1649   } else if (isExodus) {
1650     ierr = DMPlexCreateExodusFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1651   } else if (isFluent) {
1652     ierr = DMPlexCreateFluentFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1653   } else SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Cannot load file %s: unrecognized extension", filename);
1654   PetscFunctionReturn(0);
1655 }
1656 
1657 #undef __FUNCT__
1658 #define __FUNCT__ "DMPlexCreateReferenceCell"
1659 /*@
1660   DMPlexCreateReferenceCell - Create a DMPLEX with the appropriate FEM reference cell
1661 
1662   Collective on comm
1663 
1664   Input Parameters:
1665 + comm    - The communicator
1666 . dim     - The spatial dimension
1667 - simplex - Flag for simplex, otherwise use a tensor-product cell
1668 
1669   Output Parameter:
1670 . refdm - The reference cell
1671 
1672   Level: intermediate
1673 
1674 .keywords: reference cell
1675 .seealso:
1676 @*/
1677 PetscErrorCode DMPlexCreateReferenceCell(MPI_Comm comm, PetscInt dim, PetscBool simplex, DM *refdm)
1678 {
1679   DM             rdm;
1680   PetscErrorCode ierr;
1681 
1682   PetscFunctionBeginUser;
1683   ierr = DMCreate(comm, &rdm);CHKERRQ(ierr);
1684   ierr = DMSetType(rdm, DMPLEX);CHKERRQ(ierr);
1685   ierr = DMSetDimension(rdm, dim);CHKERRQ(ierr);
1686   switch (dim) {
1687   case 0:
1688   {
1689     PetscInt    numPoints[1]        = {1};
1690     PetscInt    coneSize[1]         = {0};
1691     PetscInt    cones[1]            = {0};
1692     PetscInt    coneOrientations[1] = {0};
1693     PetscScalar vertexCoords[1]     = {0.0};
1694 
1695     ierr = DMPlexCreateFromDAG(rdm, 0, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1696   }
1697   break;
1698   case 1:
1699   {
1700     PetscInt    numPoints[2]        = {2, 1};
1701     PetscInt    coneSize[3]         = {2, 0, 0};
1702     PetscInt    cones[2]            = {1, 2};
1703     PetscInt    coneOrientations[2] = {0, 0};
1704     PetscScalar vertexCoords[2]     = {-1.0,  1.0};
1705 
1706     ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1707   }
1708   break;
1709   case 2:
1710     if (simplex) {
1711       PetscInt    numPoints[2]        = {3, 1};
1712       PetscInt    coneSize[4]         = {3, 0, 0, 0};
1713       PetscInt    cones[3]            = {1, 2, 3};
1714       PetscInt    coneOrientations[3] = {0, 0, 0};
1715       PetscScalar vertexCoords[6]     = {-1.0, -1.0,  1.0, -1.0,  -1.0, 1.0};
1716 
1717       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1718     } else {
1719       PetscInt    numPoints[2]        = {4, 1};
1720       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1721       PetscInt    cones[4]            = {1, 2, 3, 4};
1722       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1723       PetscScalar vertexCoords[8]     = {-1.0, -1.0,  1.0, -1.0,  1.0, 1.0,  -1.0, 1.0};
1724 
1725       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1726     }
1727   break;
1728   case 3:
1729     if (simplex) {
1730       PetscInt    numPoints[2]        = {4, 1};
1731       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1732       PetscInt    cones[4]            = {1, 3, 2, 4};
1733       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1734       PetscScalar vertexCoords[12]    = {-1.0, -1.0, -1.0,  1.0, -1.0, -1.0,  -1.0, 1.0, -1.0,  -1.0, -1.0, 1.0};
1735 
1736       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1737     } else {
1738       PetscInt    numPoints[2]        = {8, 1};
1739       PetscInt    coneSize[9]         = {8, 0, 0, 0, 0, 0, 0, 0, 0};
1740       PetscInt    cones[8]            = {1, 4, 3, 2, 5, 6, 7, 8};
1741       PetscInt    coneOrientations[8] = {0, 0, 0, 0, 0, 0, 0, 0};
1742       PetscScalar vertexCoords[24]    = {-1.0, -1.0, -1.0,  1.0, -1.0, -1.0,  1.0, 1.0, -1.0,  -1.0, 1.0, -1.0,
1743                                          -1.0, -1.0,  1.0,  1.0, -1.0,  1.0,  1.0, 1.0,  1.0,  -1.0, 1.0,  1.0};
1744 
1745       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1746     }
1747   break;
1748   default:
1749     SETERRQ1(comm, PETSC_ERR_ARG_WRONG, "Cannot create reference cell for dimension %d", dim);
1750   }
1751   *refdm = NULL;
1752   ierr = DMPlexInterpolate(rdm, refdm);CHKERRQ(ierr);
1753   ierr = DMPlexCopyCoordinates(rdm, *refdm);CHKERRQ(ierr);
1754   ierr = DMDestroy(&rdm);CHKERRQ(ierr);
1755   PetscFunctionReturn(0);
1756 }
1757