xref: /petsc/src/dm/impls/plex/plexcreate.c (revision f66eea085cceefc5191b4b3d61f096e7c3d8e689)
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;
444   PetscInt       markerBottom   = 1;
445   PetscInt       markerFront    = 1;
446   PetscInt       markerBack     = 1;
447   PetscInt       markerRight    = 1;
448   PetscInt       markerLeft     = 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   ierr = PetscOptionsGetBool(((PetscObject) dm)->prefix, "-dm_plex_separate_marker", &markerSeparate, NULL);CHKERRQ(ierr);
458   if (markerSeparate) {
459     switch (dim) {
460     case 2:
461       markerTop    = 3;
462       markerBottom = 1;
463       markerRight  = 2;
464       markerLeft   = 4;
465       break;
466     case 3:
467       markerBottom = 1;
468       markerTop    = 2;
469       markerFront  = 3;
470       markerBack   = 4;
471       markerRight  = 5;
472       markerLeft   = 6;
473       break;
474     default:
475       SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Dimension %d not supported",dim);
476       break;
477     }
478   }
479   {
480     const PetscInt numXEdges    = !rank ? edges[0]   : 0;
481     const PetscInt numYEdges    = !rank ? edges[1]   : 0;
482     const PetscInt numZEdges    = !rank ? edges[2]   : 0;
483     const PetscInt numXVertices = !rank ? (bdX == DM_BOUNDARY_PERIODIC || bdX == DM_BOUNDARY_TWIST ? edges[0] : edges[0]+1) : 0;
484     const PetscInt numYVertices = !rank ? (bdY == DM_BOUNDARY_PERIODIC || bdY == DM_BOUNDARY_TWIST ? edges[1] : edges[1]+1) : 0;
485     const PetscInt numZVertices = !rank ? (bdZ == DM_BOUNDARY_PERIODIC || bdY == DM_BOUNDARY_TWIST ? edges[2] : edges[2]+1) : 0;
486     const PetscInt numCells     = numXEdges*numYEdges*numZEdges;
487     const PetscInt numXFaces    = numYEdges*numZEdges;
488     const PetscInt numYFaces    = numXEdges*numZEdges;
489     const PetscInt numZFaces    = numXEdges*numYEdges;
490     const PetscInt numTotXFaces = numXVertices*numXFaces;
491     const PetscInt numTotYFaces = numYVertices*numYFaces;
492     const PetscInt numTotZFaces = numZVertices*numZFaces;
493     const PetscInt numFaces     = numTotXFaces + numTotYFaces + numTotZFaces;
494     const PetscInt numTotXEdges = numXEdges*numYVertices*numZVertices;
495     const PetscInt numTotYEdges = numYEdges*numXVertices*numZVertices;
496     const PetscInt numTotZEdges = numZEdges*numXVertices*numYVertices;
497     const PetscInt numVertices  = numXVertices*numYVertices*numZVertices;
498     const PetscInt numEdges     = numTotXEdges + numTotYEdges + numTotZEdges;
499     const PetscInt firstVertex  = (dim == 2) ? numFaces : numCells;
500     const PetscInt firstXFace   = (dim == 2) ? 0 : numCells + numVertices;
501     const PetscInt firstYFace   = firstXFace + numTotXFaces;
502     const PetscInt firstZFace   = firstYFace + numTotYFaces;
503     const PetscInt firstXEdge   = numCells + numFaces + numVertices;
504     const PetscInt firstYEdge   = firstXEdge + numTotXEdges;
505     const PetscInt firstZEdge   = firstYEdge + numTotYEdges;
506     Vec            coordinates;
507     PetscSection   coordSection;
508     PetscScalar   *coords;
509     PetscInt       coordSize;
510     PetscInt       v, vx, vy, vz;
511     PetscInt       c, f, fx, fy, fz, e, ex, ey, ez;
512 
513     ierr = DMPlexSetChart(dm, 0, numCells+numFaces+numEdges+numVertices);CHKERRQ(ierr);
514     for (c = 0; c < numCells; c++) {
515       ierr = DMPlexSetConeSize(dm, c, 6);CHKERRQ(ierr);
516     }
517     for (f = firstXFace; f < firstXFace+numFaces; ++f) {
518       ierr = DMPlexSetConeSize(dm, f, 4);CHKERRQ(ierr);
519     }
520     for (e = firstXEdge; e < firstXEdge+numEdges; ++e) {
521       ierr = DMPlexSetConeSize(dm, e, 2);CHKERRQ(ierr);
522     }
523     ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
524     /* Build cells */
525     for (fz = 0; fz < numZEdges; ++fz) {
526       for (fy = 0; fy < numYEdges; ++fy) {
527         for (fx = 0; fx < numXEdges; ++fx) {
528           PetscInt cell    = (fz*numYEdges + fy)*numXEdges + fx;
529           PetscInt faceB   = firstZFace + (fy*numXEdges+fx)*numZVertices +   fz;
530           PetscInt faceT   = firstZFace + (fy*numXEdges+fx)*numZVertices + ((fz+1)%numZVertices);
531           PetscInt faceF   = firstYFace + (fz*numXEdges+fx)*numYVertices +   fy;
532           PetscInt faceK   = firstYFace + (fz*numXEdges+fx)*numYVertices + ((fy+1)%numYVertices);
533           PetscInt faceL   = firstXFace + (fz*numYEdges+fy)*numXVertices +   fx;
534           PetscInt faceR   = firstXFace + (fz*numYEdges+fy)*numXVertices + ((fx+1)%numXVertices);
535                             /* B,  T,  F,  K,  R,  L */
536           PetscInt ornt[8] = {-4,  0,  0, -1,  0, -4}; /* ??? */
537           PetscInt cone[8];
538 
539           /* no boundary twisting in 3D */
540           cone[0] = faceB; cone[1] = faceT; cone[2] = faceF; cone[3] = faceK; cone[4] = faceR; cone[5] = faceL;
541           ierr    = DMPlexSetCone(dm, cell, cone);CHKERRQ(ierr);
542           ierr    = DMPlexSetConeOrientation(dm, cell, ornt);CHKERRQ(ierr);
543         }
544       }
545     }
546     /* Build x faces */
547     for (fz = 0; fz < numZEdges; ++fz) {
548       for (fy = 0; fy < numYEdges; ++fy) {
549         for (fx = 0; fx < numXVertices; ++fx) {
550           PetscInt face    = firstXFace + (fz*numYEdges+fy)*numXVertices + fx;
551           PetscInt edgeL   = firstZEdge + (  fy*                 numXVertices+fx)*numZEdges + fz;
552           PetscInt edgeR   = firstZEdge + (((fy+1)%numYVertices)*numXVertices+fx)*numZEdges + fz;
553           PetscInt edgeB   = firstYEdge + (  fz*                 numXVertices+fx)*numYEdges + fy;
554           PetscInt edgeT   = firstYEdge + (((fz+1)%numZVertices)*numXVertices+fx)*numYEdges + fy;
555           PetscInt ornt[4] = {0, 0, -2, -2};
556           PetscInt cone[4];
557 
558           if (dim == 3) {
559             /* markers */
560             if (bdX != DM_BOUNDARY_PERIODIC) {
561               if (fx == numXVertices-1) {
562                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerRight);CHKERRQ(ierr);
563               }
564               else if (fx == 0) {
565                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerLeft);CHKERRQ(ierr);
566               }
567             }
568           }
569           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
570           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
571           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
572         }
573       }
574     }
575     /* Build y faces */
576     for (fz = 0; fz < numZEdges; ++fz) {
577       for (fx = 0; fx < numYEdges; ++fx) {
578         for (fy = 0; fy < numYVertices; ++fy) {
579           PetscInt face    = firstYFace + (fz*numXEdges+fx)*numYVertices + fy;
580           PetscInt edgeL   = firstZEdge + (fy*numXVertices+  fx                 )*numZEdges + fz;
581           PetscInt edgeR   = firstZEdge + (fy*numXVertices+((fx+1)%numXVertices))*numZEdges + fz;
582           PetscInt edgeB   = firstXEdge + (  fz                 *numYVertices+fy)*numXEdges + fx;
583           PetscInt edgeT   = firstXEdge + (((fz+1)%numZVertices)*numYVertices+fy)*numXEdges + fx;
584           PetscInt ornt[4] = {0, 0, -2, -2};
585           PetscInt cone[4];
586 
587           if (dim == 3) {
588             /* markers */
589             if (bdY != DM_BOUNDARY_PERIODIC) {
590               if (fy == numYVertices-1) {
591                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerBack);CHKERRQ(ierr);
592               }
593               else if (fy == 0) {
594                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerFront);CHKERRQ(ierr);
595               }
596             }
597           }
598           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
599           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
600           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
601         }
602       }
603     }
604     /* Build z faces */
605     for (fy = 0; fy < numYEdges; ++fy) {
606       for (fx = 0; fx < numXEdges; ++fx) {
607         for (fz = 0; fz < numZVertices; fz++) {
608           PetscInt face    = firstZFace + (fy*numXEdges+fx)*numZVertices + fz;
609           PetscInt edgeL   = firstYEdge + (fz*numXVertices+  fx                 )*numYEdges + fy;
610           PetscInt edgeR   = firstYEdge + (fz*numXVertices+((fx+1)%numXVertices))*numYEdges + fy;
611           PetscInt edgeB   = firstXEdge + (fz*numYVertices+  fy                 )*numXEdges + fx;
612           PetscInt edgeT   = firstXEdge + (fz*numYVertices+((fy+1)%numYVertices))*numXEdges + fx;
613           PetscInt ornt[4] = {0, 0, -2, -2};
614           PetscInt cone[4];
615 
616           if (dim == 2) {
617             if (bdX == DM_BOUNDARY_TWIST && fx == numXEdges-1) {edgeR += numYEdges-1-2*fy; ornt[1] = -2;}
618             if (bdY == DM_BOUNDARY_TWIST && fy == numYEdges-1) {edgeT += numXEdges-1-2*fx; ornt[2] =  0;}
619           }
620           else {
621             /* markers */
622             if (bdZ != DM_BOUNDARY_PERIODIC) {
623               if (fz == numZVertices-1) {
624                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerTop);CHKERRQ(ierr);
625               }
626               else if (fz == 0) {
627                 ierr = DMPlexSetLabelValue(dm, "marker", face, markerBottom);CHKERRQ(ierr);
628               }
629             }
630           }
631           cone[0] = edgeB; cone[1] = edgeR; cone[2] = edgeT; cone[3] = edgeL;
632           ierr    = DMPlexSetCone(dm, face, cone);CHKERRQ(ierr);
633           ierr    = DMPlexSetConeOrientation(dm, face, ornt);CHKERRQ(ierr);
634         }
635       }
636     }
637     /* Build Z edges*/
638     for (vy = 0; vy < numYVertices; vy++) {
639       for (vx = 0; vx < numXVertices; vx++) {
640         for (ez = 0; ez < numZEdges; ez++) {
641           const PetscInt edge    = firstZEdge  + (vy*numXVertices+vx)*numZEdges + ez;
642           const PetscInt vertexB = firstVertex + (  ez                 *numYVertices+vy)*numXVertices + vx;
643           const PetscInt vertexT = firstVertex + (((ez+1)%numZVertices)*numYVertices+vy)*numXVertices + vx;
644           PetscInt       cone[2];
645 
646           if (dim == 3) {
647             if (bdX != DM_BOUNDARY_PERIODIC) {
648               if (vx == numXVertices-1) {
649                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerRight);CHKERRQ(ierr);
650               }
651               else if (vx == 0) {
652                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerLeft);CHKERRQ(ierr);
653               }
654             }
655             if (bdY != DM_BOUNDARY_PERIODIC) {
656               if (vy == numYVertices-1) {
657                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBack);CHKERRQ(ierr);
658               }
659               else if (vy == 0) {
660                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerFront);CHKERRQ(ierr);
661               }
662             }
663           }
664           cone[0] = vertexB; cone[1] = vertexT;
665           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
666         }
667       }
668     }
669     /* Build Y edges*/
670     for (vz = 0; vz < numZVertices; vz++) {
671       for (vx = 0; vx < numXVertices; vx++) {
672         for (ey = 0; ey < numYEdges; ey++) {
673           const PetscInt nextv   = (dim == 2 && bdY == DM_BOUNDARY_TWIST && ey == numYEdges-1) ? (numXVertices-vx-1) : (vz*numYVertices+((ey+1)%numYVertices))*numXVertices + vx;
674           const PetscInt edge    = firstYEdge  + (vz*numXVertices+vx)*numYEdges + ey;
675           const PetscInt vertexF = firstVertex + (vz*numYVertices+ey)*numXVertices + vx;
676           const PetscInt vertexK = firstVertex + nextv;
677           PetscInt       cone[2];
678 
679           cone[0] = vertexF; cone[1] = vertexK;
680           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
681           if (dim == 2) {
682             if ((bdX != DM_BOUNDARY_PERIODIC) && (bdX != DM_BOUNDARY_TWIST)) {
683               if (vx == numXVertices-1) {
684                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerRight);CHKERRQ(ierr);
685                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerRight);CHKERRQ(ierr);
686                 if (ey == numYEdges-1) {
687                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerRight);CHKERRQ(ierr);
688                 }
689               }
690               else if (vx == 0) {
691                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerLeft);CHKERRQ(ierr);
692                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerLeft);CHKERRQ(ierr);
693                 if (ey == numYEdges-1) {
694                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerLeft);CHKERRQ(ierr);
695                 }
696               }
697             }
698           }
699           else {
700             if (bdX != DM_BOUNDARY_PERIODIC) {
701               if (vx == numXVertices-1) {
702                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerRight);CHKERRQ(ierr);
703               }
704               else if (vx == 0) {
705                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerLeft);CHKERRQ(ierr);
706               }
707             }
708             if (bdZ != DM_BOUNDARY_PERIODIC) {
709               if (vz == numZVertices-1) {
710                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerTop);CHKERRQ(ierr);
711               }
712               else if (vz == 0) {
713                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBottom);CHKERRQ(ierr);
714               }
715             }
716           }
717         }
718       }
719     }
720     /* Build X edges*/
721     for (vz = 0; vz < numZVertices; vz++) {
722       for (vy = 0; vy < numYVertices; vy++) {
723         for (ex = 0; ex < numXEdges; ex++) {
724           const PetscInt nextv   = (dim == 2 && bdX == DM_BOUNDARY_TWIST && ex == numXEdges-1) ? (numYVertices-vy-1)*numXVertices : (vz*numYVertices+vy)*numXVertices + (ex+1)%numXVertices;
725           const PetscInt edge    = firstXEdge  + (vz*numYVertices+vy)*numXEdges + ex;
726           const PetscInt vertexL = firstVertex + (vz*numYVertices+vy)*numXVertices + ex;
727           const PetscInt vertexR = firstVertex + nextv;
728           PetscInt       cone[2];
729 
730           cone[0] = vertexL; cone[1] = vertexR;
731           ierr = DMPlexSetCone(dm, edge, cone);CHKERRQ(ierr);
732           if (dim == 2) {
733             if ((bdY != DM_BOUNDARY_PERIODIC) && (bdY != DM_BOUNDARY_TWIST)) {
734               if (vy == numYVertices-1) {
735                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerTop);CHKERRQ(ierr);
736                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerTop);CHKERRQ(ierr);
737                 if (ex == numXEdges-1) {
738                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerTop);CHKERRQ(ierr);
739                 }
740               }
741               else if (vy == 0) {
742                 ierr = DMPlexSetLabelValue(dm, "marker", edge,    markerBottom);CHKERRQ(ierr);
743                 ierr = DMPlexSetLabelValue(dm, "marker", cone[0], markerBottom);CHKERRQ(ierr);
744                 if (ex == numXEdges-1) {
745                   ierr = DMPlexSetLabelValue(dm, "marker", cone[1], markerBottom);CHKERRQ(ierr);
746                 }
747               }
748             }
749           }
750           else {
751             if (bdY != DM_BOUNDARY_PERIODIC) {
752               if (vy == numYVertices-1) {
753                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBack);CHKERRQ(ierr);
754               }
755               else if (vy == 0) {
756                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerFront);CHKERRQ(ierr);
757               }
758             }
759             if (bdZ != DM_BOUNDARY_PERIODIC) {
760               if (vz == numZVertices-1) {
761                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerTop);CHKERRQ(ierr);
762               }
763               else if (vz == 0) {
764                 ierr = DMPlexSetLabelValue(dm, "marker", edge, markerBottom);CHKERRQ(ierr);
765               }
766             }
767           }
768         }
769       }
770     }
771     ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
772     ierr = DMPlexStratify(dm);CHKERRQ(ierr);
773     /* Build coordinates */
774     ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
775     ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
776     ierr = PetscSectionSetFieldComponents(coordSection, 0, dim);CHKERRQ(ierr);
777     ierr = PetscSectionSetChart(coordSection, firstVertex, firstVertex+numVertices);CHKERRQ(ierr);
778     for (v = firstVertex; v < firstVertex+numVertices; ++v) {
779       ierr = PetscSectionSetDof(coordSection, v, dim);CHKERRQ(ierr);
780       ierr = PetscSectionSetFieldDof(coordSection, v, 0, dim);CHKERRQ(ierr);
781     }
782     ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
783     ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
784     ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
785     ierr = VecSetBlockSize(coordinates, dim);CHKERRQ(ierr);
786     ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
787     ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
788     ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
789     ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
790     for (vz = 0; vz < numZVertices; ++vz) {
791       for (vy = 0; vy < numYVertices; ++vy) {
792         for (vx = 0; vx < numXVertices; ++vx) {
793           coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+0] = lower[0] + ((upper[0] - lower[0])/numXEdges)*vx;
794           coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+1] = lower[1] + ((upper[1] - lower[1])/numYEdges)*vy;
795           if (dim == 3) {
796             coords[((vz*numYVertices+vy)*numXVertices+vx)*dim+2] = lower[2] + ((upper[2] - lower[2])/numZEdges)*vz;
797           }
798         }
799       }
800     }
801     ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
802     ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
803     ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
804   }
805   PetscFunctionReturn(0);
806 }
807 
808 #undef __FUNCT__
809 #define __FUNCT__ "DMPlexCreateSquareMesh"
810 /*@
811   DMPlexCreateSquareMesh - Creates a 2D mesh for a square lattice.
812 
813   Collective on MPI_Comm
814 
815   Input Parameters:
816 + comm  - The communicator for the DM object
817 . lower - The lower left corner coordinates
818 . upper - The upper right corner coordinates
819 . edges - The number of cells in each direction
820 . bdX   - The boundary type for the X direction
821 - bdY   - The boundary type for the Y direction
822 
823   Output Parameter:
824 . dm  - The DM object
825 
826   Note: Here is the numbering returned for 2 cells in each direction:
827 $ 22--8-23--9--24
828 $  |     |     |
829 $ 13  2 14  3  15
830 $  |     |     |
831 $ 19--6-20--7--21
832 $  |     |     |
833 $ 10  0 11  1 12
834 $  |     |     |
835 $ 16--4-17--5--18
836 
837   Level: beginner
838 
839 .keywords: DM, create
840 .seealso: DMPlexCreateBoxMesh(), DMPlexCreateSquareBoundary(), DMPlexCreateCubeBoundary(), DMSetType(), DMCreate()
841 @*/
842 PetscErrorCode DMPlexCreateSquareMesh(DM dm, const PetscReal lower[], const PetscReal upper[], const PetscInt edges[], DMBoundaryType bdX, DMBoundaryType bdY)
843 {
844   PetscReal      lower3[3], upper3[3];
845   PetscInt       edges3[3];
846   PetscErrorCode ierr;
847 
848   PetscFunctionBegin;
849   lower3[0] = lower[0]; lower3[1] = lower[1]; lower3[2] = 0.;
850   upper3[0] = upper[0]; upper3[1] = upper[1]; upper3[2] = 0.;
851   edges3[0] = edges[0]; edges3[1] = edges[1]; edges3[2] = 0;
852   ierr = DMPlexCreateCubeMesh_Internal(dm, lower3, upper3, edges3, bdX, bdY, DM_BOUNDARY_NONE);CHKERRQ(ierr);
853   PetscFunctionReturn(0);
854 }
855 
856 #undef __FUNCT__
857 #define __FUNCT__ "DMPlexCreateBoxMesh"
858 /*@
859   DMPlexCreateBoxMesh - Creates a mesh on the tensor product of unit intervals (box) using simplices.
860 
861   Collective on MPI_Comm
862 
863   Input Parameters:
864 + comm - The communicator for the DM object
865 . dim - The spatial dimension
866 - interpolate - Flag to create intermediate mesh pieces (edges, faces)
867 
868   Output Parameter:
869 . dm  - The DM object
870 
871   Level: beginner
872 
873 .keywords: DM, create
874 .seealso: DMPlexCreateHexBoxMesh(), DMSetType(), DMCreate()
875 @*/
876 PetscErrorCode DMPlexCreateBoxMesh(MPI_Comm comm, PetscInt dim, PetscBool interpolate, DM *dm)
877 {
878   DM             boundary;
879   PetscErrorCode ierr;
880 
881   PetscFunctionBegin;
882   PetscValidPointer(dm, 4);
883   ierr = DMCreate(comm, &boundary);CHKERRQ(ierr);
884   PetscValidLogicalCollectiveInt(boundary,dim,2);
885   ierr = DMSetType(boundary, DMPLEX);CHKERRQ(ierr);
886   ierr = DMSetDimension(boundary, dim-1);CHKERRQ(ierr);
887   switch (dim) {
888   case 2:
889   {
890     PetscReal lower[2] = {0.0, 0.0};
891     PetscReal upper[2] = {1.0, 1.0};
892     PetscInt  edges[2] = {2, 2};
893 
894     ierr = DMPlexCreateSquareBoundary(boundary, lower, upper, edges);CHKERRQ(ierr);
895     break;
896   }
897   case 3:
898   {
899     PetscReal lower[3] = {0.0, 0.0, 0.0};
900     PetscReal upper[3] = {1.0, 1.0, 1.0};
901     PetscInt  faces[3] = {1, 1, 1};
902 
903     ierr = DMPlexCreateCubeBoundary(boundary, lower, upper, faces);CHKERRQ(ierr);
904     break;
905   }
906   default:
907     SETERRQ1(comm, PETSC_ERR_SUP, "Dimension not supported: %d", dim);
908   }
909   ierr = DMPlexGenerate(boundary, NULL, interpolate, dm);CHKERRQ(ierr);
910   ierr = DMDestroy(&boundary);CHKERRQ(ierr);
911   PetscFunctionReturn(0);
912 }
913 
914 #undef __FUNCT__
915 #define __FUNCT__ "DMPlexCreateHexBoxMesh"
916 /*@
917   DMPlexCreateHexBoxMesh - Creates a mesh on the tensor product of unit intervals (box) using hexahedra.
918 
919   Collective on MPI_Comm
920 
921   Input Parameters:
922 + comm  - The communicator for the DM object
923 . dim   - The spatial dimension
924 . periodicX - The boundary type for the X direction
925 . periodicY - The boundary type for the Y direction
926 . periodicZ - The boundary type for the Z direction
927 - cells - The number of cells in each direction
928 
929   Output Parameter:
930 . dm  - The DM object
931 
932   Level: beginner
933 
934 .keywords: DM, create
935 .seealso: DMPlexCreateBoxMesh(), DMSetType(), DMCreate()
936 @*/
937 PetscErrorCode DMPlexCreateHexBoxMesh(MPI_Comm comm, PetscInt dim, const PetscInt cells[], DMBoundaryType periodicX, DMBoundaryType periodicY, DMBoundaryType periodicZ, DM *dm)
938 {
939   PetscErrorCode ierr;
940 
941   PetscFunctionBegin;
942   PetscValidPointer(dm, 4);
943   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
944   PetscValidLogicalCollectiveInt(*dm,dim,2);
945   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
946   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
947   switch (dim) {
948   case 2:
949   {
950     PetscReal lower[2] = {0.0, 0.0};
951     PetscReal upper[2] = {1.0, 1.0};
952 
953     ierr = DMPlexCreateSquareMesh(*dm, lower, upper, cells, periodicX, periodicY);CHKERRQ(ierr);
954     break;
955   }
956   case 3:
957   {
958     PetscReal lower[3] = {0.0, 0.0, 0.0};
959     PetscReal upper[3] = {1.0, 1.0, 1.0};
960 
961     ierr = DMPlexCreateCubeMesh_Internal(*dm, lower, upper, cells, periodicX, periodicY, periodicZ);CHKERRQ(ierr);
962     break;
963   }
964   default:
965     SETERRQ1(comm, PETSC_ERR_SUP, "Dimension not supported: %d", dim);
966   }
967   PetscFunctionReturn(0);
968 }
969 
970 /* External function declarations here */
971 extern PetscErrorCode DMCreateInterpolation_Plex(DM dmCoarse, DM dmFine, Mat *interpolation, Vec *scaling);
972 extern PetscErrorCode DMCreateInjection_Plex(DM dmCoarse, DM dmFine, VecScatter *ctx);
973 extern PetscErrorCode DMCreateDefaultSection_Plex(DM dm);
974 extern PetscErrorCode DMCreateDefaultConstraints_Plex(DM dm);
975 extern PetscErrorCode DMCreateMatrix_Plex(DM dm,  Mat *J);
976 extern PetscErrorCode DMCreateCoordinateDM_Plex(DM dm, DM *cdm);
977 extern PetscErrorCode DMRefine_Plex(DM dm, MPI_Comm comm, DM *dmRefined);
978 extern PetscErrorCode DMCoarsen_Plex(DM dm, MPI_Comm comm, DM *dmCoarsened);
979 extern PetscErrorCode DMRefineHierarchy_Plex(DM dm, PetscInt nlevels, DM dmRefined[]);
980 extern PetscErrorCode DMClone_Plex(DM dm, DM *newdm);
981 extern PetscErrorCode DMSetUp_Plex(DM dm);
982 extern PetscErrorCode DMDestroy_Plex(DM dm);
983 extern PetscErrorCode DMView_Plex(DM dm, PetscViewer viewer);
984 extern PetscErrorCode DMLoad_Plex(DM dm, PetscViewer viewer);
985 extern PetscErrorCode DMCreateSubDM_Plex(DM dm, PetscInt numFields, PetscInt fields[], IS *is, DM *subdm);
986 extern PetscErrorCode DMLocatePoints_Plex(DM dm, Vec v, IS *cellIS);
987 
988 #undef __FUNCT__
989 #define __FUNCT__ "DMPlexReplace_Static"
990 /* Replace dm with the contents of dmNew
991    - Share the DM_Plex structure
992    - Share the coordinates
993    - Share the SF
994 */
995 static PetscErrorCode DMPlexReplace_Static(DM dm, DM dmNew)
996 {
997   PetscSF          sf;
998   DM               coordDM;
999   Vec              coords;
1000   const PetscReal *maxCell, *L;
1001   PetscErrorCode   ierr;
1002 
1003   PetscFunctionBegin;
1004   ierr = DMGetPointSF(dmNew, &sf);CHKERRQ(ierr);
1005   ierr = DMSetPointSF(dm, sf);CHKERRQ(ierr);
1006   ierr = DMGetCoordinateDM(dmNew, &coordDM);CHKERRQ(ierr);
1007   ierr = DMGetCoordinatesLocal(dmNew, &coords);CHKERRQ(ierr);
1008   ierr = DMSetCoordinateDM(dm, coordDM);CHKERRQ(ierr);
1009   ierr = DMSetCoordinatesLocal(dm, coords);CHKERRQ(ierr);
1010   ierr = DMGetPeriodicity(dm, &maxCell, &L);CHKERRQ(ierr);
1011   if (L) {ierr = DMSetPeriodicity(dmNew, maxCell, L);CHKERRQ(ierr);}
1012   ierr = DMDestroy_Plex(dm);CHKERRQ(ierr);
1013   dm->data = dmNew->data;
1014   ((DM_Plex *) dmNew->data)->refct++;
1015   PetscFunctionReturn(0);
1016 }
1017 
1018 #undef __FUNCT__
1019 #define __FUNCT__ "DMPlexSwap_Static"
1020 /* Swap dm with the contents of dmNew
1021    - Swap the DM_Plex structure
1022    - Swap the coordinates
1023 */
1024 static PetscErrorCode DMPlexSwap_Static(DM dmA, DM dmB)
1025 {
1026   DM             coordDMA, coordDMB;
1027   Vec            coordsA,  coordsB;
1028   void          *tmp;
1029   PetscErrorCode ierr;
1030 
1031   PetscFunctionBegin;
1032   ierr = DMGetCoordinateDM(dmA, &coordDMA);CHKERRQ(ierr);
1033   ierr = DMGetCoordinateDM(dmB, &coordDMB);CHKERRQ(ierr);
1034   ierr = PetscObjectReference((PetscObject) coordDMA);CHKERRQ(ierr);
1035   ierr = DMSetCoordinateDM(dmA, coordDMB);CHKERRQ(ierr);
1036   ierr = DMSetCoordinateDM(dmB, coordDMA);CHKERRQ(ierr);
1037   ierr = PetscObjectDereference((PetscObject) coordDMA);CHKERRQ(ierr);
1038 
1039   ierr = DMGetCoordinatesLocal(dmA, &coordsA);CHKERRQ(ierr);
1040   ierr = DMGetCoordinatesLocal(dmB, &coordsB);CHKERRQ(ierr);
1041   ierr = PetscObjectReference((PetscObject) coordsA);CHKERRQ(ierr);
1042   ierr = DMSetCoordinatesLocal(dmA, coordsB);CHKERRQ(ierr);
1043   ierr = DMSetCoordinatesLocal(dmB, coordsA);CHKERRQ(ierr);
1044   ierr = PetscObjectDereference((PetscObject) coordsA);CHKERRQ(ierr);
1045   tmp       = dmA->data;
1046   dmA->data = dmB->data;
1047   dmB->data = tmp;
1048   PetscFunctionReturn(0);
1049 }
1050 
1051 #undef __FUNCT__
1052 #define __FUNCT__ "DMSetFromOptions_NonRefinement_Plex"
1053 PetscErrorCode  DMSetFromOptions_NonRefinement_Plex(DM dm)
1054 {
1055   DM_Plex       *mesh = (DM_Plex*) dm->data;
1056   DMBoundary     b;
1057   PetscErrorCode ierr;
1058 
1059   PetscFunctionBegin;
1060   /* Handle boundary conditions */
1061   ierr = PetscOptionsBegin(PetscObjectComm((PetscObject) dm), NULL, "Boundary condition options", "");CHKERRQ(ierr);
1062   for (b = mesh->boundary; b; b = b->next) {
1063     char      optname[1024];
1064     PetscInt  ids[1024], len = 1024, i;
1065     PetscBool flg;
1066 
1067     ierr = PetscSNPrintf(optname, sizeof(optname), "-bc_%s", b->name);CHKERRQ(ierr);
1068     ierr = PetscMemzero(ids, sizeof(ids));CHKERRQ(ierr);
1069     ierr = PetscOptionsIntArray(optname, "List of boundary IDs", "", ids, &len, &flg);CHKERRQ(ierr);
1070     if (flg) {
1071       DMLabel label;
1072 
1073       ierr = DMPlexGetLabel(dm, b->labelname, &label);CHKERRQ(ierr);
1074       for (i = 0; i < len; ++i) {
1075         PetscBool has;
1076 
1077         ierr = DMLabelHasValue(label, ids[i], &has);CHKERRQ(ierr);
1078         if (!has) SETERRQ2(PetscObjectComm((PetscObject) dm), PETSC_ERR_ARG_WRONG, "Boundary id %D is not present in the label %s", ids[i], b->name);
1079       }
1080       b->numids = len;
1081       ierr = PetscFree(b->ids);CHKERRQ(ierr);
1082       ierr = PetscMalloc1(len, &b->ids);CHKERRQ(ierr);
1083       ierr = PetscMemcpy(b->ids, ids, len*sizeof(PetscInt));CHKERRQ(ierr);
1084     }
1085   }
1086   ierr = PetscOptionsEnd();CHKERRQ(ierr);
1087   /* Handle viewing */
1088   ierr = PetscOptionsBool("-dm_plex_print_set_values", "Output all set values info", "DMView", PETSC_FALSE, &mesh->printSetValues, NULL);CHKERRQ(ierr);
1089   ierr = PetscOptionsInt("-dm_plex_print_fem", "Debug output level all fem computations", "DMView", 0, &mesh->printFEM, NULL);CHKERRQ(ierr);
1090   ierr = PetscOptionsReal("-dm_plex_print_tol", "Tolerance for FEM output", "DMView", mesh->printTol, &mesh->printTol, NULL);CHKERRQ(ierr);
1091   /* Projection behavior */
1092   ierr = PetscOptionsInt("-dm_plex_max_projection_height", "Maxmimum mesh point height used to project locally", "DMPlexSetMaxProjectionHeight", 0, &mesh->maxProjectionHeight, NULL);CHKERRQ(ierr);
1093   PetscFunctionReturn(0);
1094 }
1095 
1096 #undef __FUNCT__
1097 #define __FUNCT__ "DMSetFromOptions_Plex"
1098 PetscErrorCode  DMSetFromOptions_Plex(DM dm)
1099 {
1100   PetscInt       refine = 0, r;
1101   PetscBool      isHierarchy;
1102   PetscErrorCode ierr;
1103 
1104   PetscFunctionBegin;
1105   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1106   ierr = PetscOptionsHead("DMPlex Options");CHKERRQ(ierr);
1107   /* Handle DMPlex refinement */
1108   ierr = PetscOptionsInt("-dm_refine", "The number of uniform refinements", "DMCreate", refine, &refine, NULL);CHKERRQ(ierr);
1109   ierr = PetscOptionsInt("-dm_refine_hierarchy", "The number of uniform refinements", "DMCreate", refine, &refine, &isHierarchy);CHKERRQ(ierr);
1110   if (refine) {ierr = DMPlexSetRefinementUniform(dm, PETSC_TRUE);CHKERRQ(ierr);}
1111   if (refine && isHierarchy) {
1112     DM *dms;
1113 
1114     ierr = PetscMalloc1(refine,&dms);CHKERRQ(ierr);
1115     ierr = DMRefineHierarchy(dm, refine, dms);CHKERRQ(ierr);
1116     /* Total hack since we do not pass in a pointer */
1117     ierr = DMPlexSwap_Static(dm, dms[refine-1]);CHKERRQ(ierr);
1118     if (refine == 1) {
1119       ierr = DMPlexSetCoarseDM(dm, dms[0]);CHKERRQ(ierr);
1120     } else {
1121       ierr = DMPlexSetCoarseDM(dm, dms[refine-2]);CHKERRQ(ierr);
1122       ierr = DMPlexSetCoarseDM(dms[0], dms[refine-1]);CHKERRQ(ierr);
1123     }
1124     /* Free DMs */
1125     for (r = 0; r < refine; ++r) {
1126       ierr = DMSetFromOptions_NonRefinement_Plex(dm);CHKERRQ(ierr);
1127       ierr = DMDestroy(&dms[r]);CHKERRQ(ierr);
1128     }
1129     ierr = PetscFree(dms);CHKERRQ(ierr);
1130   } else {
1131     for (r = 0; r < refine; ++r) {
1132       DM refinedMesh;
1133 
1134       ierr = DMSetFromOptions_NonRefinement_Plex(dm);CHKERRQ(ierr);
1135       ierr = DMRefine(dm, PetscObjectComm((PetscObject) dm), &refinedMesh);CHKERRQ(ierr);
1136       /* Total hack since we do not pass in a pointer */
1137       ierr = DMPlexReplace_Static(dm, refinedMesh);CHKERRQ(ierr);
1138       ierr = DMDestroy(&refinedMesh);CHKERRQ(ierr);
1139     }
1140   }
1141   ierr = DMSetFromOptions_NonRefinement_Plex(dm);CHKERRQ(ierr);
1142   ierr = PetscOptionsTail();CHKERRQ(ierr);
1143   PetscFunctionReturn(0);
1144 }
1145 
1146 #undef __FUNCT__
1147 #define __FUNCT__ "DMCreateGlobalVector_Plex"
1148 static PetscErrorCode DMCreateGlobalVector_Plex(DM dm,Vec *vec)
1149 {
1150   PetscErrorCode ierr;
1151 
1152   PetscFunctionBegin;
1153   ierr = DMCreateGlobalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1154   /* ierr = VecSetOperation(*vec, VECOP_DUPLICATE, (void(*)(void)) VecDuplicate_MPI_DM);CHKERRQ(ierr); */
1155   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex);CHKERRQ(ierr);
1156   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex);CHKERRQ(ierr);
1157   PetscFunctionReturn(0);
1158 }
1159 
1160 #undef __FUNCT__
1161 #define __FUNCT__ "DMCreateLocalVector_Plex"
1162 static PetscErrorCode DMCreateLocalVector_Plex(DM dm,Vec *vec)
1163 {
1164   PetscErrorCode ierr;
1165 
1166   PetscFunctionBegin;
1167   ierr = DMCreateLocalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1168   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex_Local);CHKERRQ(ierr);
1169   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex_Local);CHKERRQ(ierr);
1170   PetscFunctionReturn(0);
1171 }
1172 
1173 #undef __FUNCT__
1174 #define __FUNCT__ "DMGetDimPoints_Plex"
1175 static PetscErrorCode DMGetDimPoints_Plex(DM dm, PetscInt dim, PetscInt *pStart, PetscInt *pEnd)
1176 {
1177   PetscInt       depth, d;
1178   PetscErrorCode ierr;
1179 
1180   PetscFunctionBegin;
1181   ierr = DMPlexGetDepth(dm, &depth);CHKERRQ(ierr);
1182   if (depth == 1) {
1183     ierr = DMGetDimension(dm, &d);CHKERRQ(ierr);
1184     if (dim == 0)      {ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);}
1185     else if (dim == d) {ierr = DMPlexGetDepthStratum(dm, 1, pStart, pEnd);CHKERRQ(ierr);}
1186     else               {*pStart = 0; *pEnd = 0;}
1187   } else {
1188     ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);
1189   }
1190   PetscFunctionReturn(0);
1191 }
1192 
1193 #undef __FUNCT__
1194 #define __FUNCT__ "DMInitialize_Plex"
1195 PetscErrorCode DMInitialize_Plex(DM dm)
1196 {
1197   PetscFunctionBegin;
1198   dm->ops->view                            = DMView_Plex;
1199   dm->ops->load                            = DMLoad_Plex;
1200   dm->ops->setfromoptions                  = DMSetFromOptions_Plex;
1201   dm->ops->clone                           = DMClone_Plex;
1202   dm->ops->setup                           = DMSetUp_Plex;
1203   dm->ops->createdefaultsection            = DMCreateDefaultSection_Plex;
1204   dm->ops->createdefaultconstraints        = DMCreateDefaultConstraints_Plex;
1205   dm->ops->createglobalvector              = DMCreateGlobalVector_Plex;
1206   dm->ops->createlocalvector               = DMCreateLocalVector_Plex;
1207   dm->ops->getlocaltoglobalmapping         = NULL;
1208   dm->ops->createfieldis                   = NULL;
1209   dm->ops->createcoordinatedm              = DMCreateCoordinateDM_Plex;
1210   dm->ops->getcoloring                     = NULL;
1211   dm->ops->creatematrix                    = DMCreateMatrix_Plex;
1212   dm->ops->createinterpolation             = DMCreateInterpolation_Plex;
1213   dm->ops->getaggregates                   = NULL;
1214   dm->ops->getinjection                    = DMCreateInjection_Plex;
1215   dm->ops->refine                          = DMRefine_Plex;
1216   dm->ops->coarsen                         = DMCoarsen_Plex;
1217   dm->ops->refinehierarchy                 = DMRefineHierarchy_Plex;
1218   dm->ops->coarsenhierarchy                = NULL;
1219   dm->ops->globaltolocalbegin              = NULL;
1220   dm->ops->globaltolocalend                = NULL;
1221   dm->ops->localtoglobalbegin              = NULL;
1222   dm->ops->localtoglobalend                = NULL;
1223   dm->ops->destroy                         = DMDestroy_Plex;
1224   dm->ops->createsubdm                     = DMCreateSubDM_Plex;
1225   dm->ops->getdimpoints                    = DMGetDimPoints_Plex;
1226   dm->ops->locatepoints                    = DMLocatePoints_Plex;
1227   PetscFunctionReturn(0);
1228 }
1229 
1230 #undef __FUNCT__
1231 #define __FUNCT__ "DMClone_Plex"
1232 PetscErrorCode DMClone_Plex(DM dm, DM *newdm)
1233 {
1234   DM_Plex        *mesh = (DM_Plex *) dm->data;
1235   PetscErrorCode ierr;
1236 
1237   PetscFunctionBegin;
1238   mesh->refct++;
1239   (*newdm)->data = mesh;
1240   ierr = PetscObjectChangeTypeName((PetscObject) *newdm, DMPLEX);CHKERRQ(ierr);
1241   ierr = DMInitialize_Plex(*newdm);CHKERRQ(ierr);
1242   PetscFunctionReturn(0);
1243 }
1244 
1245 /*MC
1246   DMPLEX = "plex" - A DM object that encapsulates an unstructured mesh, or CW Complex, which can be expressed using a Hasse Diagram.
1247                     In the local representation, Vecs contain all unknowns in the interior and shared boundary. This is
1248                     specified by a PetscSection object. Ownership in the global representation is determined by
1249                     ownership of the underlying DMPlex points. This is specified by another PetscSection object.
1250 
1251   Level: intermediate
1252 
1253 .seealso: DMType, DMPlexCreate(), DMCreate(), DMSetType()
1254 M*/
1255 
1256 #undef __FUNCT__
1257 #define __FUNCT__ "DMCreate_Plex"
1258 PETSC_EXTERN PetscErrorCode DMCreate_Plex(DM dm)
1259 {
1260   DM_Plex        *mesh;
1261   PetscInt       unit, d;
1262   PetscErrorCode ierr;
1263 
1264   PetscFunctionBegin;
1265   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1266   ierr     = PetscNewLog(dm,&mesh);CHKERRQ(ierr);
1267   dm->dim  = 0;
1268   dm->data = mesh;
1269 
1270   mesh->refct             = 1;
1271   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->coneSection);CHKERRQ(ierr);
1272   mesh->maxConeSize       = 0;
1273   mesh->cones             = NULL;
1274   mesh->coneOrientations  = NULL;
1275   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->supportSection);CHKERRQ(ierr);
1276   mesh->maxSupportSize    = 0;
1277   mesh->supports          = NULL;
1278   mesh->refinementUniform = PETSC_TRUE;
1279   mesh->refinementLimit   = -1.0;
1280 
1281   mesh->facesTmp = NULL;
1282 
1283   mesh->tetgenOpts   = NULL;
1284   mesh->triangleOpts = NULL;
1285   ierr = PetscPartitionerCreate(PetscObjectComm((PetscObject)dm), &mesh->partitioner);CHKERRQ(ierr);
1286   ierr = PetscPartitionerSetTypeFromOptions_Internal(mesh->partitioner);CHKERRQ(ierr);
1287 
1288   mesh->subpointMap = NULL;
1289 
1290   for (unit = 0; unit < NUM_PETSC_UNITS; ++unit) mesh->scale[unit] = 1.0;
1291 
1292   mesh->labels              = NULL;
1293   mesh->depthLabel          = NULL;
1294   mesh->globalVertexNumbers = NULL;
1295   mesh->globalCellNumbers   = NULL;
1296   mesh->anchorSection       = NULL;
1297   mesh->anchorIS            = NULL;
1298   mesh->createanchors       = NULL;
1299   mesh->computeanchormatrix = NULL;
1300   mesh->parentSection       = NULL;
1301   mesh->parents             = NULL;
1302   mesh->childIDs            = NULL;
1303   mesh->childSection        = NULL;
1304   mesh->children            = NULL;
1305   mesh->referenceTree       = NULL;
1306   mesh->getchildsymmetry    = NULL;
1307   for (d = 0; d < 8; ++d) mesh->hybridPointMax[d] = PETSC_DETERMINE;
1308   mesh->vtkCellHeight       = 0;
1309   mesh->useCone             = PETSC_FALSE;
1310   mesh->useClosure          = PETSC_TRUE;
1311   mesh->useAnchors          = PETSC_FALSE;
1312 
1313   mesh->maxProjectionHeight = 0;
1314 
1315   mesh->printSetValues = PETSC_FALSE;
1316   mesh->printFEM       = 0;
1317   mesh->printTol       = 1.0e-10;
1318 
1319   ierr = DMInitialize_Plex(dm);CHKERRQ(ierr);
1320   PetscFunctionReturn(0);
1321 }
1322 
1323 #undef __FUNCT__
1324 #define __FUNCT__ "DMPlexCreate"
1325 /*@
1326   DMPlexCreate - Creates a DMPlex object, which encapsulates an unstructured mesh, or CW complex, which can be expressed using a Hasse Diagram.
1327 
1328   Collective on MPI_Comm
1329 
1330   Input Parameter:
1331 . comm - The communicator for the DMPlex object
1332 
1333   Output Parameter:
1334 . mesh  - The DMPlex object
1335 
1336   Level: beginner
1337 
1338 .keywords: DMPlex, create
1339 @*/
1340 PetscErrorCode DMPlexCreate(MPI_Comm comm, DM *mesh)
1341 {
1342   PetscErrorCode ierr;
1343 
1344   PetscFunctionBegin;
1345   PetscValidPointer(mesh,2);
1346   ierr = DMCreate(comm, mesh);CHKERRQ(ierr);
1347   ierr = DMSetType(*mesh, DMPLEX);CHKERRQ(ierr);
1348   PetscFunctionReturn(0);
1349 }
1350 
1351 #undef __FUNCT__
1352 #define __FUNCT__ "DMPlexBuildFromCellList_Private"
1353 /*
1354   This takes as input the common mesh generator output, a list of the vertices for each cell
1355 */
1356 PetscErrorCode DMPlexBuildFromCellList_Private(DM dm, PetscInt numCells, PetscInt numVertices, PetscInt numCorners, const int cells[])
1357 {
1358   PetscInt      *cone, c, p;
1359   PetscErrorCode ierr;
1360 
1361   PetscFunctionBegin;
1362   ierr = DMPlexSetChart(dm, 0, numCells+numVertices);CHKERRQ(ierr);
1363   for (c = 0; c < numCells; ++c) {
1364     ierr = DMPlexSetConeSize(dm, c, numCorners);CHKERRQ(ierr);
1365   }
1366   ierr = DMSetUp(dm);CHKERRQ(ierr);
1367   ierr = DMGetWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1368   for (c = 0; c < numCells; ++c) {
1369     for (p = 0; p < numCorners; ++p) {
1370       cone[p] = cells[c*numCorners+p]+numCells;
1371     }
1372     ierr = DMPlexSetCone(dm, c, cone);CHKERRQ(ierr);
1373   }
1374   ierr = DMRestoreWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1375   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1376   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1377   PetscFunctionReturn(0);
1378 }
1379 
1380 #undef __FUNCT__
1381 #define __FUNCT__ "DMPlexBuildCoordinates_Private"
1382 /*
1383   This takes as input the coordinates for each vertex
1384 */
1385 PetscErrorCode DMPlexBuildCoordinates_Private(DM dm, PetscInt spaceDim, PetscInt numCells, PetscInt numVertices, const double vertexCoords[])
1386 {
1387   PetscSection   coordSection;
1388   Vec            coordinates;
1389   PetscScalar   *coords;
1390   PetscInt       coordSize, v, d;
1391   PetscErrorCode ierr;
1392 
1393   PetscFunctionBegin;
1394   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1395   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1396   ierr = PetscSectionSetFieldComponents(coordSection, 0, spaceDim);CHKERRQ(ierr);
1397   ierr = PetscSectionSetChart(coordSection, numCells, numCells + numVertices);CHKERRQ(ierr);
1398   for (v = numCells; v < numCells+numVertices; ++v) {
1399     ierr = PetscSectionSetDof(coordSection, v, spaceDim);CHKERRQ(ierr);
1400     ierr = PetscSectionSetFieldDof(coordSection, v, 0, spaceDim);CHKERRQ(ierr);
1401   }
1402   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1403   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1404   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1405   ierr = VecSetBlockSize(coordinates, spaceDim);CHKERRQ(ierr);
1406   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1407   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1408   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1409   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1410   for (v = 0; v < numVertices; ++v) {
1411     for (d = 0; d < spaceDim; ++d) {
1412       coords[v*spaceDim+d] = vertexCoords[v*spaceDim+d];
1413     }
1414   }
1415   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1416   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1417   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1418   PetscFunctionReturn(0);
1419 }
1420 
1421 #undef __FUNCT__
1422 #define __FUNCT__ "DMPlexCreateFromCellList"
1423 /*@C
1424   DMPlexCreateFromCellList - This takes as input common mesh generator output, a list of the vertices for each cell, and produces a DM
1425 
1426   Input Parameters:
1427 + comm - The communicator
1428 . dim - The topological dimension of the mesh
1429 . numCells - The number of cells
1430 . numVertices - The number of vertices
1431 . numCorners - The number of vertices for each cell
1432 . interpolate - Flag indicating that intermediate mesh entities (faces, edges) should be created automatically
1433 . cells - An array of numCells*numCorners numbers, the vertices for each cell
1434 . spaceDim - The spatial dimension used for coordinates
1435 - vertexCoords - An array of numVertices*spaceDim numbers, the coordinates of each vertex
1436 
1437   Output Parameter:
1438 . dm - The DM
1439 
1440   Note: Two triangles sharing a face
1441 $
1442 $        2
1443 $      / | \
1444 $     /  |  \
1445 $    /   |   \
1446 $   0  0 | 1  3
1447 $    \   |   /
1448 $     \  |  /
1449 $      \ | /
1450 $        1
1451 would have input
1452 $  numCells = 2, numVertices = 4
1453 $  cells = [0 1 2  1 3 2]
1454 $
1455 which would result in the DMPlex
1456 $
1457 $        4
1458 $      / | \
1459 $     /  |  \
1460 $    /   |   \
1461 $   2  0 | 1  5
1462 $    \   |   /
1463 $     \  |  /
1464 $      \ | /
1465 $        3
1466 
1467   Level: beginner
1468 
1469 .seealso: DMPlexCreateFromDAG(), DMPlexCreate()
1470 @*/
1471 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)
1472 {
1473   PetscErrorCode ierr;
1474 
1475   PetscFunctionBegin;
1476   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
1477   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
1478   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
1479   ierr = DMPlexBuildFromCellList_Private(*dm, numCells, numVertices, numCorners, cells);CHKERRQ(ierr);
1480   if (interpolate) {
1481     DM idm = NULL;
1482 
1483     ierr = DMPlexInterpolate(*dm, &idm);CHKERRQ(ierr);
1484     ierr = DMDestroy(dm);CHKERRQ(ierr);
1485     *dm  = idm;
1486   }
1487   ierr = DMPlexBuildCoordinates_Private(*dm, spaceDim, numCells, numVertices, vertexCoords);CHKERRQ(ierr);
1488   PetscFunctionReturn(0);
1489 }
1490 
1491 #undef __FUNCT__
1492 #define __FUNCT__ "DMPlexCreateFromDAG"
1493 /*@
1494   DMPlexCreateFromDAG - This takes as input the adjacency-list representation of the Directed Acyclic Graph (Hasse Diagram) encoding a mesh, and produces a DM
1495 
1496   Input Parameters:
1497 + dm - The empty DM object, usually from DMCreate() and DMSetDimension()
1498 . depth - The depth of the DAG
1499 . numPoints - The number of points at each depth
1500 . coneSize - The cone size of each point
1501 . cones - The concatenation of the cone points for each point, the cone list must be oriented correctly for each point
1502 . coneOrientations - The orientation of each cone point
1503 - vertexCoords - An array of numVertices*dim numbers, the coordinates of each vertex
1504 
1505   Output Parameter:
1506 . dm - The DM
1507 
1508   Note: Two triangles sharing a face would have input
1509 $  depth = 1, numPoints = [4 2], coneSize = [3 3 0 0 0 0]
1510 $  cones = [2 3 4  3 5 4], coneOrientations = [0 0 0  0 0 0]
1511 $ vertexCoords = [-1.0 0.0  0.0 -1.0  0.0 1.0  1.0 0.0]
1512 $
1513 which would result in the DMPlex
1514 $
1515 $        4
1516 $      / | \
1517 $     /  |  \
1518 $    /   |   \
1519 $   2  0 | 1  5
1520 $    \   |   /
1521 $     \  |  /
1522 $      \ | /
1523 $        3
1524 $
1525 $ Notice that all points are numbered consecutively, unlikely DMPlexCreateFromCellList()
1526 
1527   Level: advanced
1528 
1529 .seealso: DMPlexCreateFromCellList(), DMPlexCreate()
1530 @*/
1531 PetscErrorCode DMPlexCreateFromDAG(DM dm, PetscInt depth, const PetscInt numPoints[], const PetscInt coneSize[], const PetscInt cones[], const PetscInt coneOrientations[], const PetscScalar vertexCoords[])
1532 {
1533   Vec            coordinates;
1534   PetscSection   coordSection;
1535   PetscScalar    *coords;
1536   PetscInt       coordSize, firstVertex = -1, pStart = 0, pEnd = 0, p, v, dim, dimEmbed, d, off;
1537   PetscErrorCode ierr;
1538 
1539   PetscFunctionBegin;
1540   ierr = DMGetDimension(dm, &dim);CHKERRQ(ierr);
1541   ierr = DMGetCoordinateDim(dm, &dimEmbed);CHKERRQ(ierr);
1542   if (dimEmbed < dim) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Embedding dimension %d cannot be less than intrinsic dimension %d",dimEmbed,dim);
1543   for (d = 0; d <= depth; ++d) pEnd += numPoints[d];
1544   ierr = DMPlexSetChart(dm, pStart, pEnd);CHKERRQ(ierr);
1545   for (p = pStart; p < pEnd; ++p) {
1546     ierr = DMPlexSetConeSize(dm, p, coneSize[p-pStart]);CHKERRQ(ierr);
1547     if (firstVertex < 0 && !coneSize[p - pStart]) {
1548       firstVertex = p - pStart;
1549     }
1550   }
1551   if (firstVertex < 0 && numPoints[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Expected %d vertices but could not find any", numPoints[0]);
1552   ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
1553   for (p = pStart, off = 0; p < pEnd; off += coneSize[p-pStart], ++p) {
1554     ierr = DMPlexSetCone(dm, p, &cones[off]);CHKERRQ(ierr);
1555     ierr = DMPlexSetConeOrientation(dm, p, &coneOrientations[off]);CHKERRQ(ierr);
1556   }
1557   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1558   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1559   /* Build coordinates */
1560   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1561   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1562   ierr = PetscSectionSetFieldComponents(coordSection, 0, dimEmbed);CHKERRQ(ierr);
1563   ierr = PetscSectionSetChart(coordSection, firstVertex, firstVertex+numPoints[0]);CHKERRQ(ierr);
1564   for (v = firstVertex; v < firstVertex+numPoints[0]; ++v) {
1565     ierr = PetscSectionSetDof(coordSection, v, dimEmbed);CHKERRQ(ierr);
1566     ierr = PetscSectionSetFieldDof(coordSection, v, 0, dimEmbed);CHKERRQ(ierr);
1567   }
1568   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1569   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1570   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1571   ierr = VecSetBlockSize(coordinates, dimEmbed);CHKERRQ(ierr);
1572   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1573   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1574   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1575   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1576   for (v = 0; v < numPoints[0]; ++v) {
1577     PetscInt off;
1578 
1579     ierr = PetscSectionGetOffset(coordSection, v+firstVertex, &off);CHKERRQ(ierr);
1580     for (d = 0; d < dimEmbed; ++d) {
1581       coords[off+d] = vertexCoords[v*dimEmbed+d];
1582     }
1583   }
1584   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1585   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1586   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1587   PetscFunctionReturn(0);
1588 }
1589 
1590 #undef __FUNCT__
1591 #define __FUNCT__ "DMPlexCreateFromFile"
1592 /*@C
1593   DMPlexCreateFromFile - This takes a filename and produces a DM
1594 
1595   Input Parameters:
1596 + comm - The communicator
1597 . filename - A file name
1598 - interpolate - Flag to create intermediate mesh pieces (edges, faces)
1599 
1600   Output Parameter:
1601 . dm - The DM
1602 
1603   Level: beginner
1604 
1605 .seealso: DMPlexCreateFromDAG(), DMPlexCreateFromCellList(), DMPlexCreate()
1606 @*/
1607 PetscErrorCode DMPlexCreateFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
1608 {
1609   const char    *extGmsh   = ".msh";
1610   const char    *extCGNS   = ".cgns";
1611   const char    *extExodus = ".exo";
1612   size_t         len;
1613   PetscBool      isGmsh, isCGNS, isExodus;
1614   PetscMPIInt    rank;
1615   PetscErrorCode ierr;
1616 
1617   PetscFunctionBegin;
1618   PetscValidPointer(filename, 2);
1619   PetscValidPointer(dm, 4);
1620   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
1621   ierr = PetscStrlen(filename, &len);CHKERRQ(ierr);
1622   if (!len) SETERRQ(comm, PETSC_ERR_ARG_WRONG, "Filename must be a valid path");
1623   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extGmsh,   4, &isGmsh);CHKERRQ(ierr);
1624   ierr = PetscStrncmp(&filename[PetscMax(0,len-5)], extCGNS,   5, &isCGNS);CHKERRQ(ierr);
1625   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extExodus, 4, &isExodus);CHKERRQ(ierr);
1626   if (isGmsh) {
1627     PetscViewer viewer;
1628 
1629     ierr = PetscViewerCreate(comm, &viewer);CHKERRQ(ierr);
1630     ierr = PetscViewerSetType(viewer, PETSCVIEWERASCII);CHKERRQ(ierr);
1631     ierr = PetscViewerFileSetMode(viewer, FILE_MODE_READ);CHKERRQ(ierr);
1632     ierr = PetscViewerFileSetName(viewer, filename);CHKERRQ(ierr);
1633     ierr = DMPlexCreateGmsh(comm, viewer, interpolate, dm);CHKERRQ(ierr);
1634     ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
1635   } else if (isCGNS) {
1636     ierr = DMPlexCreateCGNSFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1637   } else if (isExodus) {
1638     ierr = DMPlexCreateExodusFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1639   } else SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Cannot load file %s: unrecognized extension", filename);
1640   PetscFunctionReturn(0);
1641 }
1642 
1643 #undef __FUNCT__
1644 #define __FUNCT__ "DMPlexCreateReferenceCell"
1645 /*@
1646   DMPlexCreateReferenceCell - Create a DMPLEX with the appropriate FEM reference cell
1647 
1648   Collective on comm
1649 
1650   Input Parameters:
1651 + comm    - The communicator
1652 . dim     - The spatial dimension
1653 - simplex - Flag for simplex, otherwise use a tensor-product cell
1654 
1655   Output Parameter:
1656 . refdm - The reference cell
1657 
1658   Level: intermediate
1659 
1660 .keywords: reference cell
1661 .seealso:
1662 @*/
1663 PetscErrorCode DMPlexCreateReferenceCell(MPI_Comm comm, PetscInt dim, PetscBool simplex, DM *refdm)
1664 {
1665   DM             rdm;
1666   PetscErrorCode ierr;
1667 
1668   PetscFunctionBeginUser;
1669   ierr = DMCreate(comm, &rdm);CHKERRQ(ierr);
1670   ierr = DMSetType(rdm, DMPLEX);CHKERRQ(ierr);
1671   ierr = DMSetDimension(rdm, dim);CHKERRQ(ierr);
1672   switch (dim) {
1673   case 0:
1674   {
1675     PetscInt    numPoints[1]        = {1};
1676     PetscInt    coneSize[1]         = {0};
1677     PetscInt    cones[1]            = {0};
1678     PetscInt    coneOrientations[1] = {0};
1679     PetscScalar vertexCoords[1]     = {0.0};
1680 
1681     ierr = DMPlexCreateFromDAG(rdm, 0, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1682   }
1683   break;
1684   case 1:
1685   {
1686     PetscInt    numPoints[2]        = {2, 1};
1687     PetscInt    coneSize[3]         = {2, 0, 0};
1688     PetscInt    cones[2]            = {1, 2};
1689     PetscInt    coneOrientations[2] = {0, 0};
1690     PetscScalar vertexCoords[2]     = {-1.0,  1.0};
1691 
1692     ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1693   }
1694   break;
1695   case 2:
1696     if (simplex) {
1697       PetscInt    numPoints[2]        = {3, 1};
1698       PetscInt    coneSize[4]         = {3, 0, 0, 0};
1699       PetscInt    cones[3]            = {1, 2, 3};
1700       PetscInt    coneOrientations[3] = {0, 0, 0};
1701       PetscScalar vertexCoords[6]     = {-1.0, -1.0,  1.0, -1.0,  -1.0, 1.0};
1702 
1703       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1704     } else {
1705       PetscInt    numPoints[2]        = {4, 1};
1706       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1707       PetscInt    cones[4]            = {1, 2, 3, 4};
1708       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1709       PetscScalar vertexCoords[8]     = {-1.0, -1.0,  1.0, -1.0,  1.0, 1.0,  -1.0, 1.0};
1710 
1711       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1712     }
1713   break;
1714   case 3:
1715     if (simplex) {
1716       PetscInt    numPoints[2]        = {4, 1};
1717       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1718       PetscInt    cones[4]            = {1, 3, 2, 4};
1719       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1720       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};
1721 
1722       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1723     } else {
1724       PetscInt    numPoints[2]        = {8, 1};
1725       PetscInt    coneSize[9]         = {8, 0, 0, 0, 0, 0, 0, 0, 0};
1726       PetscInt    cones[8]            = {1, 4, 3, 2, 5, 6, 7, 8};
1727       PetscInt    coneOrientations[8] = {0, 0, 0, 0, 0, 0, 0, 0};
1728       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,
1729                                          -1.0, -1.0,  1.0,  1.0, -1.0,  1.0,  1.0, 1.0,  1.0,  -1.0, 1.0,  1.0};
1730 
1731       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1732     }
1733   break;
1734   default:
1735     SETERRQ1(comm, PETSC_ERR_ARG_WRONG, "Cannot create reference cell for dimension %d", dim);
1736   }
1737   *refdm = NULL;
1738   ierr = DMPlexInterpolate(rdm, refdm);CHKERRQ(ierr);
1739   ierr = DMPlexCopyCoordinates(rdm, *refdm);CHKERRQ(ierr);
1740   ierr = DMDestroy(&rdm);CHKERRQ(ierr);
1741   PetscFunctionReturn(0);
1742 }
1743