xref: /petsc/src/dm/impls/plex/plexcreate.c (revision a6404fbfb1cfbf30d2bac9856cef3bf7411483d5)
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   const PetscInt numVertices    = (edges[0]+1)*(edges[1]+1);
188   const 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    = 3;
206     markerBottom = 1;
207     markerRight  = 2;
208     markerLeft   = 4;
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 DMCoarsenHierarchy_Plex(DM dm, PetscInt nlevels, DM dmCoarsened[]);
997 extern PetscErrorCode DMClone_Plex(DM dm, DM *newdm);
998 extern PetscErrorCode DMSetUp_Plex(DM dm);
999 extern PetscErrorCode DMDestroy_Plex(DM dm);
1000 extern PetscErrorCode DMView_Plex(DM dm, PetscViewer viewer);
1001 extern PetscErrorCode DMLoad_Plex(DM dm, PetscViewer viewer);
1002 extern PetscErrorCode DMCreateSubDM_Plex(DM dm, PetscInt numFields, PetscInt fields[], IS *is, DM *subdm);
1003 extern PetscErrorCode DMLocatePoints_Plex(DM dm, Vec v, IS *cellIS);
1004 
1005 #undef __FUNCT__
1006 #define __FUNCT__ "DMPlexReplace_Static"
1007 /* Replace dm with the contents of dmNew
1008    - Share the DM_Plex structure
1009    - Share the coordinates
1010    - Share the SF
1011 */
1012 static PetscErrorCode DMPlexReplace_Static(DM dm, DM dmNew)
1013 {
1014   PetscSF          sf;
1015   DM               coordDM;
1016   Vec              coords;
1017   const PetscReal *maxCell, *L;
1018   const DMBoundaryType *bd;
1019   PetscErrorCode   ierr;
1020 
1021   PetscFunctionBegin;
1022   ierr = DMGetPointSF(dmNew, &sf);CHKERRQ(ierr);
1023   ierr = DMSetPointSF(dm, sf);CHKERRQ(ierr);
1024   ierr = DMGetCoordinateDM(dmNew, &coordDM);CHKERRQ(ierr);
1025   ierr = DMGetCoordinatesLocal(dmNew, &coords);CHKERRQ(ierr);
1026   ierr = DMSetCoordinateDM(dm, coordDM);CHKERRQ(ierr);
1027   ierr = DMSetCoordinatesLocal(dm, coords);CHKERRQ(ierr);
1028   ierr = DMGetPeriodicity(dm, &maxCell, &L, &bd);CHKERRQ(ierr);
1029   if (L) {ierr = DMSetPeriodicity(dmNew, maxCell, L, bd);CHKERRQ(ierr);}
1030   ierr = DMDestroy_Plex(dm);CHKERRQ(ierr);
1031   dm->data = dmNew->data;
1032   ((DM_Plex *) dmNew->data)->refct++;
1033   PetscFunctionReturn(0);
1034 }
1035 
1036 #undef __FUNCT__
1037 #define __FUNCT__ "DMPlexSwap_Static"
1038 /* Swap dm with the contents of dmNew
1039    - Swap the DM_Plex structure
1040    - Swap the coordinates
1041 */
1042 static PetscErrorCode DMPlexSwap_Static(DM dmA, DM dmB)
1043 {
1044   DM             coordDMA, coordDMB;
1045   Vec            coordsA,  coordsB;
1046   void          *tmp;
1047   PetscErrorCode ierr;
1048 
1049   PetscFunctionBegin;
1050   ierr = DMGetCoordinateDM(dmA, &coordDMA);CHKERRQ(ierr);
1051   ierr = DMGetCoordinateDM(dmB, &coordDMB);CHKERRQ(ierr);
1052   ierr = PetscObjectReference((PetscObject) coordDMA);CHKERRQ(ierr);
1053   ierr = DMSetCoordinateDM(dmA, coordDMB);CHKERRQ(ierr);
1054   ierr = DMSetCoordinateDM(dmB, coordDMA);CHKERRQ(ierr);
1055   ierr = PetscObjectDereference((PetscObject) coordDMA);CHKERRQ(ierr);
1056 
1057   ierr = DMGetCoordinatesLocal(dmA, &coordsA);CHKERRQ(ierr);
1058   ierr = DMGetCoordinatesLocal(dmB, &coordsB);CHKERRQ(ierr);
1059   ierr = PetscObjectReference((PetscObject) coordsA);CHKERRQ(ierr);
1060   ierr = DMSetCoordinatesLocal(dmA, coordsB);CHKERRQ(ierr);
1061   ierr = DMSetCoordinatesLocal(dmB, coordsA);CHKERRQ(ierr);
1062   ierr = PetscObjectDereference((PetscObject) coordsA);CHKERRQ(ierr);
1063   tmp       = dmA->data;
1064   dmA->data = dmB->data;
1065   dmB->data = tmp;
1066   PetscFunctionReturn(0);
1067 }
1068 
1069 #undef __FUNCT__
1070 #define __FUNCT__ "DMSetFromOptions_NonRefinement_Plex"
1071 PetscErrorCode  DMSetFromOptions_NonRefinement_Plex(PetscOptions *PetscOptionsObject,DM dm)
1072 {
1073   DM_Plex       *mesh = (DM_Plex*) dm->data;
1074   DMBoundary     b;
1075   PetscErrorCode ierr;
1076 
1077   PetscFunctionBegin;
1078   /* Handle boundary conditions */
1079   ierr = PetscOptionsBegin(PetscObjectComm((PetscObject) dm), NULL, "Boundary condition options", "");CHKERRQ(ierr);
1080   for (b = mesh->boundary; b; b = b->next) {
1081     char      optname[1024];
1082     PetscInt  ids[1024], len = 1024, i;
1083     PetscBool flg;
1084 
1085     ierr = PetscSNPrintf(optname, sizeof(optname), "-bc_%s", b->name);CHKERRQ(ierr);
1086     ierr = PetscMemzero(ids, sizeof(ids));CHKERRQ(ierr);
1087     ierr = PetscOptionsIntArray(optname, "List of boundary IDs", "", ids, &len, &flg);CHKERRQ(ierr);
1088     if (flg) {
1089       DMLabel label;
1090 
1091       ierr = DMPlexGetLabel(dm, b->labelname, &label);CHKERRQ(ierr);
1092       for (i = 0; i < len; ++i) {
1093         PetscBool has;
1094 
1095         ierr = DMLabelHasValue(label, ids[i], &has);CHKERRQ(ierr);
1096         if (!has) SETERRQ2(PetscObjectComm((PetscObject) dm), PETSC_ERR_ARG_WRONG, "Boundary id %D is not present in the label %s", ids[i], b->name);
1097       }
1098       b->numids = len;
1099       ierr = PetscFree(b->ids);CHKERRQ(ierr);
1100       ierr = PetscMalloc1(len, &b->ids);CHKERRQ(ierr);
1101       ierr = PetscMemcpy(b->ids, ids, len*sizeof(PetscInt));CHKERRQ(ierr);
1102     }
1103     ierr = PetscSNPrintf(optname, sizeof(optname), "-bc_%s_comp", b->name);CHKERRQ(ierr);
1104     ierr = PetscMemzero(ids, sizeof(ids));CHKERRQ(ierr);
1105     ierr = PetscOptionsIntArray(optname, "List of boundary field components", "", ids, &len, &flg);CHKERRQ(ierr);
1106     if (flg) {
1107       b->numcomps = len;
1108       ierr = PetscFree(b->comps);CHKERRQ(ierr);
1109       ierr = PetscMalloc1(len, &b->comps);CHKERRQ(ierr);
1110       ierr = PetscMemcpy(b->comps, ids, len*sizeof(PetscInt));CHKERRQ(ierr);
1111     }
1112   }
1113   ierr = PetscOptionsEnd();CHKERRQ(ierr);
1114   /* Handle viewing */
1115   ierr = PetscOptionsBool("-dm_plex_print_set_values", "Output all set values info", "DMView", PETSC_FALSE, &mesh->printSetValues, NULL);CHKERRQ(ierr);
1116   ierr = PetscOptionsInt("-dm_plex_print_fem", "Debug output level all fem computations", "DMView", 0, &mesh->printFEM, NULL);CHKERRQ(ierr);
1117   ierr = PetscOptionsReal("-dm_plex_print_tol", "Tolerance for FEM output", "DMView", mesh->printTol, &mesh->printTol, NULL);CHKERRQ(ierr);
1118   /* Projection behavior */
1119   ierr = PetscOptionsInt("-dm_plex_max_projection_height", "Maxmimum mesh point height used to project locally", "DMPlexSetMaxProjectionHeight", 0, &mesh->maxProjectionHeight, NULL);CHKERRQ(ierr);
1120   PetscFunctionReturn(0);
1121 }
1122 
1123 #undef __FUNCT__
1124 #define __FUNCT__ "DMSetFromOptions_Plex"
1125 PetscErrorCode  DMSetFromOptions_Plex(PetscOptions *PetscOptionsObject,DM dm)
1126 {
1127   PetscInt       refine = 0, coarsen = 0, r;
1128   PetscBool      isHierarchy;
1129   PetscErrorCode ierr;
1130 
1131   PetscFunctionBegin;
1132   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1133   ierr = PetscOptionsHead(PetscOptionsObject,"DMPlex Options");CHKERRQ(ierr);
1134   /* Handle DMPlex refinement */
1135   ierr = PetscOptionsInt("-dm_refine", "The number of uniform refinements", "DMCreate", refine, &refine, NULL);CHKERRQ(ierr);
1136   ierr = PetscOptionsInt("-dm_refine_hierarchy", "The number of uniform refinements", "DMCreate", refine, &refine, &isHierarchy);CHKERRQ(ierr);
1137   if (refine) {ierr = DMPlexSetRefinementUniform(dm, PETSC_TRUE);CHKERRQ(ierr);}
1138   if (refine && isHierarchy) {
1139     DM *dms;
1140 
1141     ierr = PetscMalloc1(refine,&dms);CHKERRQ(ierr);
1142     ierr = DMRefineHierarchy(dm, refine, dms);CHKERRQ(ierr);
1143     /* Total hack since we do not pass in a pointer */
1144     ierr = DMPlexSwap_Static(dm, dms[refine-1]);CHKERRQ(ierr);
1145     if (refine == 1) {
1146       ierr = DMPlexSetCoarseDM(dm, dms[0]);CHKERRQ(ierr);
1147       ierr = DMPlexSetRegularRefinement(dm, PETSC_TRUE);CHKERRQ(ierr);
1148     } else {
1149       ierr = DMPlexSetCoarseDM(dm, dms[refine-2]);CHKERRQ(ierr);
1150       ierr = DMPlexSetRegularRefinement(dm, PETSC_TRUE);CHKERRQ(ierr);
1151       ierr = DMPlexSetCoarseDM(dms[0], dms[refine-1]);CHKERRQ(ierr);
1152       ierr = DMPlexSetRegularRefinement(dms[0], PETSC_TRUE);CHKERRQ(ierr);
1153     }
1154     /* Free DMs */
1155     for (r = 0; r < refine; ++r) {
1156       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject, dm);CHKERRQ(ierr);
1157       ierr = DMDestroy(&dms[r]);CHKERRQ(ierr);
1158     }
1159     ierr = PetscFree(dms);CHKERRQ(ierr);
1160   } else {
1161     for (r = 0; r < refine; ++r) {
1162       DM refinedMesh;
1163 
1164       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject, dm);CHKERRQ(ierr);
1165       ierr = DMRefine(dm, PetscObjectComm((PetscObject) dm), &refinedMesh);CHKERRQ(ierr);
1166       /* Total hack since we do not pass in a pointer */
1167       ierr = DMPlexReplace_Static(dm, refinedMesh);CHKERRQ(ierr);
1168       ierr = DMDestroy(&refinedMesh);CHKERRQ(ierr);
1169     }
1170   }
1171   /* Handle DMPlex coarsening */
1172   ierr = PetscOptionsInt("-dm_coarsen", "Coarsen the mesh", "DMCreate", coarsen, &coarsen, NULL);CHKERRQ(ierr);
1173   ierr = PetscOptionsInt("-dm_coarsen_hierarchy", "The number of coarsenings", "DMCreate", coarsen, &coarsen, &isHierarchy);CHKERRQ(ierr);
1174   if (coarsen && isHierarchy) {
1175     DM *dms;
1176 
1177     ierr = PetscMalloc1(coarsen, &dms);CHKERRQ(ierr);
1178     ierr = DMCoarsenHierarchy(dm, coarsen, dms);CHKERRQ(ierr);
1179     /* Free DMs */
1180     for (r = 0; r < coarsen; ++r) {
1181       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject, dm);CHKERRQ(ierr);
1182       ierr = DMDestroy(&dms[r]);CHKERRQ(ierr);
1183     }
1184     ierr = PetscFree(dms);CHKERRQ(ierr);
1185   } else {
1186     for (r = 0; r < coarsen; ++r) {
1187       DM coarseMesh;
1188 
1189       ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject, dm);CHKERRQ(ierr);
1190       ierr = DMCoarsen(dm, PetscObjectComm((PetscObject) dm), &coarseMesh);CHKERRQ(ierr);
1191       /* Total hack since we do not pass in a pointer */
1192       ierr = DMPlexReplace_Static(dm, coarseMesh);CHKERRQ(ierr);
1193       ierr = DMDestroy(&coarseMesh);CHKERRQ(ierr);
1194     }
1195   }
1196   /* Handle */
1197   ierr = DMSetFromOptions_NonRefinement_Plex(PetscOptionsObject, dm);CHKERRQ(ierr);
1198   ierr = PetscOptionsTail();CHKERRQ(ierr);
1199   PetscFunctionReturn(0);
1200 }
1201 
1202 #undef __FUNCT__
1203 #define __FUNCT__ "DMCreateGlobalVector_Plex"
1204 static PetscErrorCode DMCreateGlobalVector_Plex(DM dm,Vec *vec)
1205 {
1206   PetscErrorCode ierr;
1207 
1208   PetscFunctionBegin;
1209   ierr = DMCreateGlobalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1210   /* ierr = VecSetOperation(*vec, VECOP_DUPLICATE, (void(*)(void)) VecDuplicate_MPI_DM);CHKERRQ(ierr); */
1211   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex);CHKERRQ(ierr);
1212   ierr = VecSetOperation(*vec, VECOP_VIEWNATIVE, (void (*)(void)) VecView_Plex_Native);CHKERRQ(ierr);
1213   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex);CHKERRQ(ierr);
1214   ierr = VecSetOperation(*vec, VECOP_LOADNATIVE, (void (*)(void)) VecLoad_Plex_Native);CHKERRQ(ierr);
1215   PetscFunctionReturn(0);
1216 }
1217 
1218 #undef __FUNCT__
1219 #define __FUNCT__ "DMCreateLocalVector_Plex"
1220 static PetscErrorCode DMCreateLocalVector_Plex(DM dm,Vec *vec)
1221 {
1222   PetscErrorCode ierr;
1223 
1224   PetscFunctionBegin;
1225   ierr = DMCreateLocalVector_Section_Private(dm,vec);CHKERRQ(ierr);
1226   ierr = VecSetOperation(*vec, VECOP_VIEW, (void (*)(void)) VecView_Plex_Local);CHKERRQ(ierr);
1227   ierr = VecSetOperation(*vec, VECOP_LOAD, (void (*)(void)) VecLoad_Plex_Local);CHKERRQ(ierr);
1228   PetscFunctionReturn(0);
1229 }
1230 
1231 #undef __FUNCT__
1232 #define __FUNCT__ "DMGetDimPoints_Plex"
1233 static PetscErrorCode DMGetDimPoints_Plex(DM dm, PetscInt dim, PetscInt *pStart, PetscInt *pEnd)
1234 {
1235   PetscInt       depth, d;
1236   PetscErrorCode ierr;
1237 
1238   PetscFunctionBegin;
1239   ierr = DMPlexGetDepth(dm, &depth);CHKERRQ(ierr);
1240   if (depth == 1) {
1241     ierr = DMGetDimension(dm, &d);CHKERRQ(ierr);
1242     if (dim == 0)      {ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);}
1243     else if (dim == d) {ierr = DMPlexGetDepthStratum(dm, 1, pStart, pEnd);CHKERRQ(ierr);}
1244     else               {*pStart = 0; *pEnd = 0;}
1245   } else {
1246     ierr = DMPlexGetDepthStratum(dm, dim, pStart, pEnd);CHKERRQ(ierr);
1247   }
1248   PetscFunctionReturn(0);
1249 }
1250 
1251 #undef __FUNCT__
1252 #define __FUNCT__ "DMInitialize_Plex"
1253 PetscErrorCode DMInitialize_Plex(DM dm)
1254 {
1255   PetscFunctionBegin;
1256   dm->ops->view                            = DMView_Plex;
1257   dm->ops->load                            = DMLoad_Plex;
1258   dm->ops->setfromoptions                  = DMSetFromOptions_Plex;
1259   dm->ops->clone                           = DMClone_Plex;
1260   dm->ops->setup                           = DMSetUp_Plex;
1261   dm->ops->createdefaultsection            = DMCreateDefaultSection_Plex;
1262   dm->ops->createdefaultconstraints        = DMCreateDefaultConstraints_Plex;
1263   dm->ops->createglobalvector              = DMCreateGlobalVector_Plex;
1264   dm->ops->createlocalvector               = DMCreateLocalVector_Plex;
1265   dm->ops->getlocaltoglobalmapping         = NULL;
1266   dm->ops->createfieldis                   = NULL;
1267   dm->ops->createcoordinatedm              = DMCreateCoordinateDM_Plex;
1268   dm->ops->getcoloring                     = NULL;
1269   dm->ops->creatematrix                    = DMCreateMatrix_Plex;
1270   dm->ops->createinterpolation             = DMCreateInterpolation_Plex;
1271   dm->ops->getaggregates                   = NULL;
1272   dm->ops->getinjection                    = DMCreateInjection_Plex;
1273   dm->ops->refine                          = DMRefine_Plex;
1274   dm->ops->coarsen                         = DMCoarsen_Plex;
1275   dm->ops->refinehierarchy                 = DMRefineHierarchy_Plex;
1276   dm->ops->coarsenhierarchy                = DMCoarsenHierarchy_Plex;
1277   dm->ops->globaltolocalbegin              = NULL;
1278   dm->ops->globaltolocalend                = NULL;
1279   dm->ops->localtoglobalbegin              = NULL;
1280   dm->ops->localtoglobalend                = NULL;
1281   dm->ops->destroy                         = DMDestroy_Plex;
1282   dm->ops->createsubdm                     = DMCreateSubDM_Plex;
1283   dm->ops->getdimpoints                    = DMGetDimPoints_Plex;
1284   dm->ops->locatepoints                    = DMLocatePoints_Plex;
1285   PetscFunctionReturn(0);
1286 }
1287 
1288 #undef __FUNCT__
1289 #define __FUNCT__ "DMClone_Plex"
1290 PetscErrorCode DMClone_Plex(DM dm, DM *newdm)
1291 {
1292   DM_Plex        *mesh = (DM_Plex *) dm->data;
1293   PetscErrorCode ierr;
1294 
1295   PetscFunctionBegin;
1296   mesh->refct++;
1297   (*newdm)->data = mesh;
1298   ierr = PetscObjectChangeTypeName((PetscObject) *newdm, DMPLEX);CHKERRQ(ierr);
1299   ierr = DMInitialize_Plex(*newdm);CHKERRQ(ierr);
1300   PetscFunctionReturn(0);
1301 }
1302 
1303 /*MC
1304   DMPLEX = "plex" - A DM object that encapsulates an unstructured mesh, or CW Complex, which can be expressed using a Hasse Diagram.
1305                     In the local representation, Vecs contain all unknowns in the interior and shared boundary. This is
1306                     specified by a PetscSection object. Ownership in the global representation is determined by
1307                     ownership of the underlying DMPlex points. This is specified by another PetscSection object.
1308 
1309   Level: intermediate
1310 
1311 .seealso: DMType, DMPlexCreate(), DMCreate(), DMSetType()
1312 M*/
1313 
1314 #undef __FUNCT__
1315 #define __FUNCT__ "DMCreate_Plex"
1316 PETSC_EXTERN PetscErrorCode DMCreate_Plex(DM dm)
1317 {
1318   DM_Plex        *mesh;
1319   PetscInt       unit, d;
1320   PetscErrorCode ierr;
1321 
1322   PetscFunctionBegin;
1323   PetscValidHeaderSpecific(dm, DM_CLASSID, 1);
1324   ierr     = PetscNewLog(dm,&mesh);CHKERRQ(ierr);
1325   dm->dim  = 0;
1326   dm->data = mesh;
1327 
1328   mesh->refct             = 1;
1329   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->coneSection);CHKERRQ(ierr);
1330   mesh->maxConeSize       = 0;
1331   mesh->cones             = NULL;
1332   mesh->coneOrientations  = NULL;
1333   ierr                    = PetscSectionCreate(PetscObjectComm((PetscObject)dm), &mesh->supportSection);CHKERRQ(ierr);
1334   mesh->maxSupportSize    = 0;
1335   mesh->supports          = NULL;
1336   mesh->refinementUniform = PETSC_TRUE;
1337   mesh->refinementLimit   = -1.0;
1338 
1339   mesh->facesTmp = NULL;
1340 
1341   mesh->tetgenOpts   = NULL;
1342   mesh->triangleOpts = NULL;
1343   ierr = PetscPartitionerCreate(PetscObjectComm((PetscObject)dm), &mesh->partitioner);CHKERRQ(ierr);
1344   ierr = PetscPartitionerSetTypeFromOptions_Internal(mesh->partitioner);CHKERRQ(ierr);
1345 
1346   mesh->subpointMap = NULL;
1347 
1348   for (unit = 0; unit < NUM_PETSC_UNITS; ++unit) mesh->scale[unit] = 1.0;
1349 
1350   mesh->coarseMesh          = NULL;
1351   mesh->regularRefinement   = PETSC_FALSE;
1352   mesh->labels              = NULL;
1353   mesh->depthLabel          = NULL;
1354   mesh->depthState          = -1;
1355   mesh->globalVertexNumbers = NULL;
1356   mesh->globalCellNumbers   = NULL;
1357   mesh->anchorSection       = NULL;
1358   mesh->anchorIS            = NULL;
1359   mesh->createanchors       = NULL;
1360   mesh->computeanchormatrix = NULL;
1361   mesh->parentSection       = NULL;
1362   mesh->parents             = NULL;
1363   mesh->childIDs            = NULL;
1364   mesh->childSection        = NULL;
1365   mesh->children            = NULL;
1366   mesh->referenceTree       = NULL;
1367   mesh->getchildsymmetry    = NULL;
1368   for (d = 0; d < 8; ++d) mesh->hybridPointMax[d] = PETSC_DETERMINE;
1369   mesh->vtkCellHeight       = 0;
1370   mesh->useCone             = PETSC_FALSE;
1371   mesh->useClosure          = PETSC_TRUE;
1372   mesh->useAnchors          = PETSC_FALSE;
1373 
1374   mesh->maxProjectionHeight = 0;
1375 
1376   mesh->printSetValues = PETSC_FALSE;
1377   mesh->printFEM       = 0;
1378   mesh->printTol       = 1.0e-10;
1379 
1380   ierr = DMInitialize_Plex(dm);CHKERRQ(ierr);
1381   PetscFunctionReturn(0);
1382 }
1383 
1384 #undef __FUNCT__
1385 #define __FUNCT__ "DMPlexCreate"
1386 /*@
1387   DMPlexCreate - Creates a DMPlex object, which encapsulates an unstructured mesh, or CW complex, which can be expressed using a Hasse Diagram.
1388 
1389   Collective on MPI_Comm
1390 
1391   Input Parameter:
1392 . comm - The communicator for the DMPlex object
1393 
1394   Output Parameter:
1395 . mesh  - The DMPlex object
1396 
1397   Level: beginner
1398 
1399 .keywords: DMPlex, create
1400 @*/
1401 PetscErrorCode DMPlexCreate(MPI_Comm comm, DM *mesh)
1402 {
1403   PetscErrorCode ierr;
1404 
1405   PetscFunctionBegin;
1406   PetscValidPointer(mesh,2);
1407   ierr = DMCreate(comm, mesh);CHKERRQ(ierr);
1408   ierr = DMSetType(*mesh, DMPLEX);CHKERRQ(ierr);
1409   PetscFunctionReturn(0);
1410 }
1411 
1412 #undef __FUNCT__
1413 #define __FUNCT__ "DMPlexBuildFromCellList_Private"
1414 /*
1415   This takes as input the common mesh generator output, a list of the vertices for each cell
1416 */
1417 PetscErrorCode DMPlexBuildFromCellList_Private(DM dm, PetscInt numCells, PetscInt numVertices, PetscInt numCorners, const int cells[])
1418 {
1419   PetscInt      *cone, c, p;
1420   PetscErrorCode ierr;
1421 
1422   PetscFunctionBegin;
1423   ierr = DMPlexSetChart(dm, 0, numCells+numVertices);CHKERRQ(ierr);
1424   for (c = 0; c < numCells; ++c) {
1425     ierr = DMPlexSetConeSize(dm, c, numCorners);CHKERRQ(ierr);
1426   }
1427   ierr = DMSetUp(dm);CHKERRQ(ierr);
1428   ierr = DMGetWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1429   for (c = 0; c < numCells; ++c) {
1430     for (p = 0; p < numCorners; ++p) {
1431       cone[p] = cells[c*numCorners+p]+numCells;
1432     }
1433     ierr = DMPlexSetCone(dm, c, cone);CHKERRQ(ierr);
1434   }
1435   ierr = DMRestoreWorkArray(dm, numCorners, PETSC_INT, &cone);CHKERRQ(ierr);
1436   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1437   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1438   PetscFunctionReturn(0);
1439 }
1440 
1441 #undef __FUNCT__
1442 #define __FUNCT__ "DMPlexBuildCoordinates_Private"
1443 /*
1444   This takes as input the coordinates for each vertex
1445 */
1446 PetscErrorCode DMPlexBuildCoordinates_Private(DM dm, PetscInt spaceDim, PetscInt numCells, PetscInt numVertices, const double vertexCoords[])
1447 {
1448   PetscSection   coordSection;
1449   Vec            coordinates;
1450   PetscScalar   *coords;
1451   PetscInt       coordSize, v, d;
1452   PetscErrorCode ierr;
1453 
1454   PetscFunctionBegin;
1455   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1456   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1457   ierr = PetscSectionSetFieldComponents(coordSection, 0, spaceDim);CHKERRQ(ierr);
1458   ierr = PetscSectionSetChart(coordSection, numCells, numCells + numVertices);CHKERRQ(ierr);
1459   for (v = numCells; v < numCells+numVertices; ++v) {
1460     ierr = PetscSectionSetDof(coordSection, v, spaceDim);CHKERRQ(ierr);
1461     ierr = PetscSectionSetFieldDof(coordSection, v, 0, spaceDim);CHKERRQ(ierr);
1462   }
1463   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1464   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1465   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1466   ierr = VecSetBlockSize(coordinates, spaceDim);CHKERRQ(ierr);
1467   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1468   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1469   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1470   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1471   for (v = 0; v < numVertices; ++v) {
1472     for (d = 0; d < spaceDim; ++d) {
1473       coords[v*spaceDim+d] = vertexCoords[v*spaceDim+d];
1474     }
1475   }
1476   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1477   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1478   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1479   PetscFunctionReturn(0);
1480 }
1481 
1482 #undef __FUNCT__
1483 #define __FUNCT__ "DMPlexCreateFromCellList"
1484 /*@C
1485   DMPlexCreateFromCellList - This takes as input common mesh generator output, a list of the vertices for each cell, and produces a DM
1486 
1487   Input Parameters:
1488 + comm - The communicator
1489 . dim - The topological dimension of the mesh
1490 . numCells - The number of cells
1491 . numVertices - The number of vertices
1492 . numCorners - The number of vertices for each cell
1493 . interpolate - Flag indicating that intermediate mesh entities (faces, edges) should be created automatically
1494 . cells - An array of numCells*numCorners numbers, the vertices for each cell
1495 . spaceDim - The spatial dimension used for coordinates
1496 - vertexCoords - An array of numVertices*spaceDim numbers, the coordinates of each vertex
1497 
1498   Output Parameter:
1499 . dm - The DM
1500 
1501   Note: Two triangles sharing a face
1502 $
1503 $        2
1504 $      / | \
1505 $     /  |  \
1506 $    /   |   \
1507 $   0  0 | 1  3
1508 $    \   |   /
1509 $     \  |  /
1510 $      \ | /
1511 $        1
1512 would have input
1513 $  numCells = 2, numVertices = 4
1514 $  cells = [0 1 2  1 3 2]
1515 $
1516 which would result in the DMPlex
1517 $
1518 $        4
1519 $      / | \
1520 $     /  |  \
1521 $    /   |   \
1522 $   2  0 | 1  5
1523 $    \   |   /
1524 $     \  |  /
1525 $      \ | /
1526 $        3
1527 
1528   Level: beginner
1529 
1530 .seealso: DMPlexCreateFromDAG(), DMPlexCreate()
1531 @*/
1532 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)
1533 {
1534   PetscErrorCode ierr;
1535 
1536   PetscFunctionBegin;
1537   ierr = DMCreate(comm, dm);CHKERRQ(ierr);
1538   ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
1539   ierr = DMSetDimension(*dm, dim);CHKERRQ(ierr);
1540   ierr = DMPlexBuildFromCellList_Private(*dm, numCells, numVertices, numCorners, cells);CHKERRQ(ierr);
1541   if (interpolate) {
1542     DM idm = NULL;
1543 
1544     ierr = DMPlexInterpolate(*dm, &idm);CHKERRQ(ierr);
1545     ierr = DMDestroy(dm);CHKERRQ(ierr);
1546     *dm  = idm;
1547   }
1548   ierr = DMPlexBuildCoordinates_Private(*dm, spaceDim, numCells, numVertices, vertexCoords);CHKERRQ(ierr);
1549   PetscFunctionReturn(0);
1550 }
1551 
1552 #undef __FUNCT__
1553 #define __FUNCT__ "DMPlexCreateFromDAG"
1554 /*@
1555   DMPlexCreateFromDAG - This takes as input the adjacency-list representation of the Directed Acyclic Graph (Hasse Diagram) encoding a mesh, and produces a DM
1556 
1557   Input Parameters:
1558 + dm - The empty DM object, usually from DMCreate() and DMSetDimension()
1559 . depth - The depth of the DAG
1560 . numPoints - The number of points at each depth
1561 . coneSize - The cone size of each point
1562 . cones - The concatenation of the cone points for each point, the cone list must be oriented correctly for each point
1563 . coneOrientations - The orientation of each cone point
1564 - vertexCoords - An array of numVertices*dim numbers, the coordinates of each vertex
1565 
1566   Output Parameter:
1567 . dm - The DM
1568 
1569   Note: Two triangles sharing a face would have input
1570 $  depth = 1, numPoints = [4 2], coneSize = [3 3 0 0 0 0]
1571 $  cones = [2 3 4  3 5 4], coneOrientations = [0 0 0  0 0 0]
1572 $ vertexCoords = [-1.0 0.0  0.0 -1.0  0.0 1.0  1.0 0.0]
1573 $
1574 which would result in the DMPlex
1575 $
1576 $        4
1577 $      / | \
1578 $     /  |  \
1579 $    /   |   \
1580 $   2  0 | 1  5
1581 $    \   |   /
1582 $     \  |  /
1583 $      \ | /
1584 $        3
1585 $
1586 $ Notice that all points are numbered consecutively, unlikely DMPlexCreateFromCellList()
1587 
1588   Level: advanced
1589 
1590 .seealso: DMPlexCreateFromCellList(), DMPlexCreate()
1591 @*/
1592 PetscErrorCode DMPlexCreateFromDAG(DM dm, PetscInt depth, const PetscInt numPoints[], const PetscInt coneSize[], const PetscInt cones[], const PetscInt coneOrientations[], const PetscScalar vertexCoords[])
1593 {
1594   Vec            coordinates;
1595   PetscSection   coordSection;
1596   PetscScalar    *coords;
1597   PetscInt       coordSize, firstVertex = -1, pStart = 0, pEnd = 0, p, v, dim, dimEmbed, d, off;
1598   PetscErrorCode ierr;
1599 
1600   PetscFunctionBegin;
1601   ierr = DMGetDimension(dm, &dim);CHKERRQ(ierr);
1602   ierr = DMGetCoordinateDim(dm, &dimEmbed);CHKERRQ(ierr);
1603   if (dimEmbed < dim) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Embedding dimension %d cannot be less than intrinsic dimension %d",dimEmbed,dim);
1604   for (d = 0; d <= depth; ++d) pEnd += numPoints[d];
1605   ierr = DMPlexSetChart(dm, pStart, pEnd);CHKERRQ(ierr);
1606   for (p = pStart; p < pEnd; ++p) {
1607     ierr = DMPlexSetConeSize(dm, p, coneSize[p-pStart]);CHKERRQ(ierr);
1608     if (firstVertex < 0 && !coneSize[p - pStart]) {
1609       firstVertex = p - pStart;
1610     }
1611   }
1612   if (firstVertex < 0 && numPoints[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Expected %d vertices but could not find any", numPoints[0]);
1613   ierr = DMSetUp(dm);CHKERRQ(ierr); /* Allocate space for cones */
1614   for (p = pStart, off = 0; p < pEnd; off += coneSize[p-pStart], ++p) {
1615     ierr = DMPlexSetCone(dm, p, &cones[off]);CHKERRQ(ierr);
1616     ierr = DMPlexSetConeOrientation(dm, p, &coneOrientations[off]);CHKERRQ(ierr);
1617   }
1618   ierr = DMPlexSymmetrize(dm);CHKERRQ(ierr);
1619   ierr = DMPlexStratify(dm);CHKERRQ(ierr);
1620   /* Build coordinates */
1621   ierr = DMGetCoordinateSection(dm, &coordSection);CHKERRQ(ierr);
1622   ierr = PetscSectionSetNumFields(coordSection, 1);CHKERRQ(ierr);
1623   ierr = PetscSectionSetFieldComponents(coordSection, 0, dimEmbed);CHKERRQ(ierr);
1624   ierr = PetscSectionSetChart(coordSection, firstVertex, firstVertex+numPoints[0]);CHKERRQ(ierr);
1625   for (v = firstVertex; v < firstVertex+numPoints[0]; ++v) {
1626     ierr = PetscSectionSetDof(coordSection, v, dimEmbed);CHKERRQ(ierr);
1627     ierr = PetscSectionSetFieldDof(coordSection, v, 0, dimEmbed);CHKERRQ(ierr);
1628   }
1629   ierr = PetscSectionSetUp(coordSection);CHKERRQ(ierr);
1630   ierr = PetscSectionGetStorageSize(coordSection, &coordSize);CHKERRQ(ierr);
1631   ierr = VecCreate(PetscObjectComm((PetscObject)dm), &coordinates);CHKERRQ(ierr);
1632   ierr = VecSetBlockSize(coordinates, dimEmbed);CHKERRQ(ierr);
1633   ierr = PetscObjectSetName((PetscObject) coordinates, "coordinates");CHKERRQ(ierr);
1634   ierr = VecSetSizes(coordinates, coordSize, PETSC_DETERMINE);CHKERRQ(ierr);
1635   ierr = VecSetType(coordinates,VECSTANDARD);CHKERRQ(ierr);
1636   ierr = VecGetArray(coordinates, &coords);CHKERRQ(ierr);
1637   for (v = 0; v < numPoints[0]; ++v) {
1638     PetscInt off;
1639 
1640     ierr = PetscSectionGetOffset(coordSection, v+firstVertex, &off);CHKERRQ(ierr);
1641     for (d = 0; d < dimEmbed; ++d) {
1642       coords[off+d] = vertexCoords[v*dimEmbed+d];
1643     }
1644   }
1645   ierr = VecRestoreArray(coordinates, &coords);CHKERRQ(ierr);
1646   ierr = DMSetCoordinatesLocal(dm, coordinates);CHKERRQ(ierr);
1647   ierr = VecDestroy(&coordinates);CHKERRQ(ierr);
1648   PetscFunctionReturn(0);
1649 }
1650 
1651 #undef __FUNCT__
1652 #define __FUNCT__ "DMPlexCreateFromFile"
1653 /*@C
1654   DMPlexCreateFromFile - This takes a filename and produces a DM
1655 
1656   Input Parameters:
1657 + comm - The communicator
1658 . filename - A file name
1659 - interpolate - Flag to create intermediate mesh pieces (edges, faces)
1660 
1661   Output Parameter:
1662 . dm - The DM
1663 
1664   Level: beginner
1665 
1666 .seealso: DMPlexCreateFromDAG(), DMPlexCreateFromCellList(), DMPlexCreate()
1667 @*/
1668 PetscErrorCode DMPlexCreateFromFile(MPI_Comm comm, const char filename[], PetscBool interpolate, DM *dm)
1669 {
1670   const char    *extGmsh   = ".msh";
1671   const char    *extCGNS   = ".cgns";
1672   const char    *extExodus = ".exo";
1673   const char    *extFluent = ".cas";
1674   const char    *extHDF5   = ".h5";
1675   size_t         len;
1676   PetscBool      isGmsh, isCGNS, isExodus, isFluent, isHDF5;
1677   PetscMPIInt    rank;
1678   PetscErrorCode ierr;
1679 
1680   PetscFunctionBegin;
1681   PetscValidPointer(filename, 2);
1682   PetscValidPointer(dm, 4);
1683   ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr);
1684   ierr = PetscStrlen(filename, &len);CHKERRQ(ierr);
1685   if (!len) SETERRQ(comm, PETSC_ERR_ARG_WRONG, "Filename must be a valid path");
1686   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extGmsh,   4, &isGmsh);CHKERRQ(ierr);
1687   ierr = PetscStrncmp(&filename[PetscMax(0,len-5)], extCGNS,   5, &isCGNS);CHKERRQ(ierr);
1688   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extExodus, 4, &isExodus);CHKERRQ(ierr);
1689   ierr = PetscStrncmp(&filename[PetscMax(0,len-4)], extFluent, 4, &isFluent);CHKERRQ(ierr);
1690   ierr = PetscStrncmp(&filename[PetscMax(0,len-3)], extHDF5,   3, &isHDF5);CHKERRQ(ierr);
1691   if (isGmsh) {
1692     ierr = DMPlexCreateGmshFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1693   } else if (isCGNS) {
1694     ierr = DMPlexCreateCGNSFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1695   } else if (isExodus) {
1696     ierr = DMPlexCreateExodusFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1697   } else if (isFluent) {
1698     ierr = DMPlexCreateFluentFromFile(comm, filename, interpolate, dm);CHKERRQ(ierr);
1699   } else if (isHDF5) {
1700     PetscViewer viewer;
1701 
1702     ierr = PetscViewerCreate(comm, &viewer);CHKERRQ(ierr);
1703     ierr = PetscViewerSetType(viewer, PETSCVIEWERHDF5);CHKERRQ(ierr);
1704     ierr = PetscViewerFileSetMode(viewer, FILE_MODE_READ);CHKERRQ(ierr);
1705     ierr = PetscViewerFileSetName(viewer, filename);CHKERRQ(ierr);
1706     ierr = DMCreate(comm, dm);CHKERRQ(ierr);
1707     ierr = DMSetType(*dm, DMPLEX);CHKERRQ(ierr);
1708     ierr = DMLoad(*dm, viewer);CHKERRQ(ierr);
1709     ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
1710   } else SETERRQ1(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONG, "Cannot load file %s: unrecognized extension", filename);
1711   PetscFunctionReturn(0);
1712 }
1713 
1714 #undef __FUNCT__
1715 #define __FUNCT__ "DMPlexCreateReferenceCell"
1716 /*@
1717   DMPlexCreateReferenceCell - Create a DMPLEX with the appropriate FEM reference cell
1718 
1719   Collective on comm
1720 
1721   Input Parameters:
1722 + comm    - The communicator
1723 . dim     - The spatial dimension
1724 - simplex - Flag for simplex, otherwise use a tensor-product cell
1725 
1726   Output Parameter:
1727 . refdm - The reference cell
1728 
1729   Level: intermediate
1730 
1731 .keywords: reference cell
1732 .seealso:
1733 @*/
1734 PetscErrorCode DMPlexCreateReferenceCell(MPI_Comm comm, PetscInt dim, PetscBool simplex, DM *refdm)
1735 {
1736   DM             rdm;
1737   PetscErrorCode ierr;
1738 
1739   PetscFunctionBeginUser;
1740   ierr = DMCreate(comm, &rdm);CHKERRQ(ierr);
1741   ierr = DMSetType(rdm, DMPLEX);CHKERRQ(ierr);
1742   ierr = DMSetDimension(rdm, dim);CHKERRQ(ierr);
1743   switch (dim) {
1744   case 0:
1745   {
1746     PetscInt    numPoints[1]        = {1};
1747     PetscInt    coneSize[1]         = {0};
1748     PetscInt    cones[1]            = {0};
1749     PetscInt    coneOrientations[1] = {0};
1750     PetscScalar vertexCoords[1]     = {0.0};
1751 
1752     ierr = DMPlexCreateFromDAG(rdm, 0, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1753   }
1754   break;
1755   case 1:
1756   {
1757     PetscInt    numPoints[2]        = {2, 1};
1758     PetscInt    coneSize[3]         = {2, 0, 0};
1759     PetscInt    cones[2]            = {1, 2};
1760     PetscInt    coneOrientations[2] = {0, 0};
1761     PetscScalar vertexCoords[2]     = {-1.0,  1.0};
1762 
1763     ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1764   }
1765   break;
1766   case 2:
1767     if (simplex) {
1768       PetscInt    numPoints[2]        = {3, 1};
1769       PetscInt    coneSize[4]         = {3, 0, 0, 0};
1770       PetscInt    cones[3]            = {1, 2, 3};
1771       PetscInt    coneOrientations[3] = {0, 0, 0};
1772       PetscScalar vertexCoords[6]     = {-1.0, -1.0,  1.0, -1.0,  -1.0, 1.0};
1773 
1774       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1775     } else {
1776       PetscInt    numPoints[2]        = {4, 1};
1777       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1778       PetscInt    cones[4]            = {1, 2, 3, 4};
1779       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1780       PetscScalar vertexCoords[8]     = {-1.0, -1.0,  1.0, -1.0,  1.0, 1.0,  -1.0, 1.0};
1781 
1782       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1783     }
1784   break;
1785   case 3:
1786     if (simplex) {
1787       PetscInt    numPoints[2]        = {4, 1};
1788       PetscInt    coneSize[5]         = {4, 0, 0, 0, 0};
1789       PetscInt    cones[4]            = {1, 3, 2, 4};
1790       PetscInt    coneOrientations[4] = {0, 0, 0, 0};
1791       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};
1792 
1793       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1794     } else {
1795       PetscInt    numPoints[2]        = {8, 1};
1796       PetscInt    coneSize[9]         = {8, 0, 0, 0, 0, 0, 0, 0, 0};
1797       PetscInt    cones[8]            = {1, 4, 3, 2, 5, 6, 7, 8};
1798       PetscInt    coneOrientations[8] = {0, 0, 0, 0, 0, 0, 0, 0};
1799       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,
1800                                          -1.0, -1.0,  1.0,  1.0, -1.0,  1.0,  1.0, 1.0,  1.0,  -1.0, 1.0,  1.0};
1801 
1802       ierr = DMPlexCreateFromDAG(rdm, 1, numPoints, coneSize, cones, coneOrientations, vertexCoords);CHKERRQ(ierr);
1803     }
1804   break;
1805   default:
1806     SETERRQ1(comm, PETSC_ERR_ARG_WRONG, "Cannot create reference cell for dimension %d", dim);
1807   }
1808   *refdm = NULL;
1809   ierr = DMPlexInterpolate(rdm, refdm);CHKERRQ(ierr);
1810   ierr = DMPlexCopyCoordinates(rdm, *refdm);CHKERRQ(ierr);
1811   ierr = DMDestroy(&rdm);CHKERRQ(ierr);
1812   PetscFunctionReturn(0);
1813 }
1814