Actual source code: ex6.c

  1: static char help[] = "Spectral element access patterns with Plex\n\n";

  3: #include <petscdmplex.h>

  5: typedef struct {
  6:   PetscInt  Nf; /* Number of fields */
  7:   PetscInt *Nc; /* Number of components per field */
  8:   PetscInt *k;  /* Spectral order per field */
  9: } AppCtx;

 11: static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
 12: {
 13:   PetscInt  len;
 14:   PetscBool flg;

 17:   options->Nf = 0;
 18:   options->Nc = NULL;
 19:   options->k  = NULL;

 21:   PetscOptionsBegin(comm, "", "SEM Problem Options", "DMPLEX");
 22:   PetscOptionsBoundedInt("-num_fields", "The number of fields", "ex6.c", options->Nf, &options->Nf, NULL, 0);
 23:   if (options->Nf) {
 24:     len = options->Nf;
 25:     PetscMalloc1(len, &options->Nc);
 26:     PetscOptionsIntArray("-num_components", "The number of components per field", "ex6.c", options->Nc, &len, &flg);
 28:     len = options->Nf;
 29:     PetscMalloc1(len, &options->k);
 30:     PetscOptionsIntArray("-order", "The spectral order per field", "ex6.c", options->k, &len, &flg);
 32:   }
 33:   PetscOptionsEnd();
 34:   return 0;
 35: }

 37: static PetscErrorCode LoadData2D(DM dm, PetscInt Ni, PetscInt Nj, PetscInt clSize, Vec u, AppCtx *user)
 38: {
 39:   PetscInt     i, j, f, c;
 40:   PetscScalar *closure;

 43:   PetscMalloc1(clSize, &closure);
 44:   for (j = 0; j < Nj; ++j) {
 45:     for (i = 0; i < Ni; ++i) {
 46:       PetscInt ki, kj, o = 0;
 47:       PetscArrayzero(closure, clSize);

 49:       for (f = 0; f < user->Nf; ++f) {
 50:         PetscInt ioff = i * user->k[f], joff = j * user->k[f];

 52:         for (kj = 0; kj <= user->k[f]; ++kj) {
 53:           for (ki = 0; ki <= user->k[f]; ++ki) {
 54:             for (c = 0; c < user->Nc[f]; ++c) closure[o++] = ((kj + joff) * (Ni * user->k[f] + 1) + ki + ioff) * user->Nc[f] + c;
 55:           }
 56:         }
 57:       }
 58:       DMPlexVecSetClosure(dm, NULL, u, j * Ni + i, closure, INSERT_VALUES);
 59:     }
 60:   }
 61:   PetscFree(closure);
 62:   return 0;
 63: }

 65: static PetscErrorCode LoadData3D(DM dm, PetscInt Ni, PetscInt Nj, PetscInt Nk, PetscInt clSize, Vec u, AppCtx *user)
 66: {
 67:   PetscInt     i, j, k, f, c;
 68:   PetscScalar *closure;

 71:   PetscMalloc1(clSize, &closure);
 72:   for (k = 0; k < Nk; ++k) {
 73:     for (j = 0; j < Nj; ++j) {
 74:       for (i = 0; i < Ni; ++i) {
 75:         PetscInt ki, kj, kk, o = 0;
 76:         PetscArrayzero(closure, clSize);

 78:         for (f = 0; f < user->Nf; ++f) {
 79:           PetscInt ioff = i * user->k[f], joff = j * user->k[f], koff = k * user->k[f];

 81:           for (kk = 0; kk <= user->k[f]; ++kk) {
 82:             for (kj = 0; kj <= user->k[f]; ++kj) {
 83:               for (ki = 0; ki <= user->k[f]; ++ki) {
 84:                 for (c = 0; c < user->Nc[f]; ++c) closure[o++] = (((kk + koff) * (Nj * user->k[f] + 1) + kj + joff) * (Ni * user->k[f] + 1) + ki + ioff) * user->Nc[f] + c;
 85:               }
 86:             }
 87:           }
 88:         }
 89:         DMPlexVecSetClosure(dm, NULL, u, (k * Nj + j) * Ni + i, closure, INSERT_VALUES);
 90:       }
 91:     }
 92:   }
 93:   PetscFree(closure);
 94:   return 0;
 95: }

 97: static PetscErrorCode CheckPoint(DM dm, Vec u, PetscInt point, AppCtx *user)
 98: {
 99:   PetscSection       s;
100:   PetscScalar       *a;
101:   const PetscScalar *array;
102:   PetscInt           dof, d;

105:   DMGetLocalSection(dm, &s);
106:   VecGetArrayRead(u, &array);
107:   DMPlexPointLocalRead(dm, point, array, &a);
108:   PetscSectionGetDof(s, point, &dof);
109:   PetscPrintf(PETSC_COMM_SELF, "Point %" PetscInt_FMT ": ", point);
110:   for (d = 0; d < dof; ++d) {
111:     if (d > 0) PetscPrintf(PETSC_COMM_SELF, ", ");
112:     PetscPrintf(PETSC_COMM_SELF, "%2.0f", (double)PetscRealPart(a[d]));
113:   }
114:   PetscPrintf(PETSC_COMM_SELF, "\n");
115:   VecRestoreArrayRead(u, &array);
116:   return 0;
117: }

119: static PetscErrorCode ReadData2D(DM dm, Vec u, AppCtx *user)
120: {
121:   PetscInt cStart, cEnd, cell;

124:   DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd);
125:   for (cell = cStart; cell < cEnd; ++cell) {
126:     PetscScalar *closure = NULL;
127:     PetscInt     closureSize, ki, kj, f, c, foff = 0;

129:     DMPlexVecGetClosure(dm, NULL, u, cell, &closureSize, &closure);
130:     PetscPrintf(PETSC_COMM_SELF, "Cell %" PetscInt_FMT "\n", cell);
131:     for (f = 0; f < user->Nf; ++f) {
132:       PetscPrintf(PETSC_COMM_SELF, "  Field %" PetscInt_FMT "\n", f);
133:       for (kj = user->k[f]; kj >= 0; --kj) {
134:         for (ki = 0; ki <= user->k[f]; ++ki) {
135:           if (ki > 0) PetscPrintf(PETSC_COMM_SELF, "  ");
136:           for (c = 0; c < user->Nc[f]; ++c) {
137:             if (c > 0) PetscPrintf(PETSC_COMM_SELF, ",");
138:             PetscPrintf(PETSC_COMM_SELF, "%2.0f", (double)PetscRealPart(closure[(kj * (user->k[f] + 1) + ki) * user->Nc[f] + c + foff]));
139:           }
140:         }
141:         PetscPrintf(PETSC_COMM_SELF, "\n");
142:       }
143:       PetscPrintf(PETSC_COMM_SELF, "\n\n");
144:       foff += PetscSqr(user->k[f] + 1);
145:     }
146:     DMPlexVecRestoreClosure(dm, NULL, u, cell, &closureSize, &closure);
147:     PetscPrintf(PETSC_COMM_SELF, "\n\n");
148:   }
149:   return 0;
150: }

152: static PetscErrorCode ReadData3D(DM dm, Vec u, AppCtx *user)
153: {
154:   PetscInt cStart, cEnd, cell;

157:   DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd);
158:   for (cell = cStart; cell < cEnd; ++cell) {
159:     PetscScalar *closure = NULL;
160:     PetscInt     closureSize, ki, kj, kk, f, c, foff = 0;

162:     DMPlexVecGetClosure(dm, NULL, u, cell, &closureSize, &closure);
163:     PetscPrintf(PETSC_COMM_SELF, "Cell %" PetscInt_FMT "\n", cell);
164:     for (f = 0; f < user->Nf; ++f) {
165:       PetscPrintf(PETSC_COMM_SELF, "  Field %" PetscInt_FMT "\n", f);
166:       for (kk = user->k[f]; kk >= 0; --kk) {
167:         for (kj = user->k[f]; kj >= 0; --kj) {
168:           for (ki = 0; ki <= user->k[f]; ++ki) {
169:             if (ki > 0) PetscPrintf(PETSC_COMM_SELF, "  ");
170:             for (c = 0; c < user->Nc[f]; ++c) {
171:               if (c > 0) PetscPrintf(PETSC_COMM_SELF, ",");
172:               PetscPrintf(PETSC_COMM_SELF, "%2.0f", (double)PetscRealPart(closure[((kk * (user->k[f] + 1) + kj) * (user->k[f] + 1) + ki) * user->Nc[f] + c + foff]));
173:             }
174:           }
175:           PetscPrintf(PETSC_COMM_SELF, "\n");
176:         }
177:         PetscPrintf(PETSC_COMM_SELF, "\n");
178:       }
179:       PetscPrintf(PETSC_COMM_SELF, "\n\n");
180:       foff += PetscSqr(user->k[f] + 1);
181:     }
182:     DMPlexVecRestoreClosure(dm, NULL, u, cell, &closureSize, &closure);
183:     PetscPrintf(PETSC_COMM_SELF, "\n\n");
184:   }
185:   return 0;
186: }

188: static PetscErrorCode SetSymmetries(DM dm, PetscSection s, AppCtx *user)
189: {
190:   PetscInt dim, f, o, i, j, k, c, d;
191:   DMLabel  depthLabel;

193:   DMGetDimension(dm, &dim);
194:   DMGetLabel(dm, "depth", &depthLabel);
195:   for (f = 0; f < user->Nf; f++) {
196:     PetscSectionSym sym;

198:     if (user->k[f] < 3) continue; /* No symmetries needed for order < 3, because no cell, facet, edge or vertex has more than one node */
199:     PetscSectionSymCreateLabel(PetscObjectComm((PetscObject)s), depthLabel, &sym);

201:     for (d = 0; d <= dim; d++) {
202:       if (d == 1) {
203:         PetscInt   numDof  = user->k[f] - 1;
204:         PetscInt   numComp = user->Nc[f];
205:         PetscInt   minOrnt = -1;
206:         PetscInt   maxOrnt = 1;
207:         PetscInt **perms;

209:         PetscCalloc1(maxOrnt - minOrnt, &perms);
210:         for (o = minOrnt; o < maxOrnt; o++) {
211:           PetscInt *perm;

213:           if (!o) { /* identity */
214:             perms[o - minOrnt] = NULL;
215:           } else {
216:             PetscMalloc1(numDof * numComp, &perm);
217:             for (i = numDof - 1, k = 0; i >= 0; i--) {
218:               for (j = 0; j < numComp; j++, k++) perm[k] = i * numComp + j;
219:             }
220:             perms[o - minOrnt] = perm;
221:           }
222:         }
223:         PetscSectionSymLabelSetStratum(sym, d, numDof * numComp, minOrnt, maxOrnt, PETSC_OWN_POINTER, (const PetscInt **)perms, NULL);
224:       } else if (d == 2) {
225:         PetscInt   perEdge = user->k[f] - 1;
226:         PetscInt   numDof  = perEdge * perEdge;
227:         PetscInt   numComp = user->Nc[f];
228:         PetscInt   minOrnt = -4;
229:         PetscInt   maxOrnt = 4;
230:         PetscInt **perms;

232:         PetscCalloc1(maxOrnt - minOrnt, &perms);
233:         for (o = minOrnt; o < maxOrnt; o++) {
234:           PetscInt *perm;

236:           if (!o) continue; /* identity */
237:           PetscMalloc1(numDof * numComp, &perm);
238:           /* We want to perm[k] to list which *localArray* position the *sectionArray* position k should go to for the given orientation*/
239:           switch (o) {
240:           case 0:
241:             break; /* identity */
242:           case -2: /* flip along (-1,-1)--( 1, 1), which swaps edges 0 and 3 and edges 1 and 2.  This swaps the i and j variables */
243:             for (i = 0, k = 0; i < perEdge; i++) {
244:               for (j = 0; j < perEdge; j++, k++) {
245:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * j + i) * numComp + c;
246:               }
247:             }
248:             break;
249:           case -1: /* flip along (-1, 0)--( 1, 0), which swaps edges 0 and 2.  This reverses the i variable */
250:             for (i = 0, k = 0; i < perEdge; i++) {
251:               for (j = 0; j < perEdge; j++, k++) {
252:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * (perEdge - 1 - i) + j) * numComp + c;
253:               }
254:             }
255:             break;
256:           case -4: /* flip along ( 1,-1)--(-1, 1), which swaps edges 0 and 1 and edges 2 and 3.  This swaps the i and j variables and reverse both */
257:             for (i = 0, k = 0; i < perEdge; i++) {
258:               for (j = 0; j < perEdge; j++, k++) {
259:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * (perEdge - 1 - j) + (perEdge - 1 - i)) * numComp + c;
260:               }
261:             }
262:             break;
263:           case -3: /* flip along ( 0,-1)--( 0, 1), which swaps edges 3 and 1.  This reverses the j variable */
264:             for (i = 0, k = 0; i < perEdge; i++) {
265:               for (j = 0; j < perEdge; j++, k++) {
266:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * i + (perEdge - 1 - j)) * numComp + c;
267:               }
268:             }
269:             break;
270:           case 1: /* rotate section edge 1 to local edge 0.  This swaps the i and j variables and then reverses the j variable */
271:             for (i = 0, k = 0; i < perEdge; i++) {
272:               for (j = 0; j < perEdge; j++, k++) {
273:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * (perEdge - 1 - j) + i) * numComp + c;
274:               }
275:             }
276:             break;
277:           case 2: /* rotate section edge 2 to local edge 0.  This reverse both i and j variables */
278:             for (i = 0, k = 0; i < perEdge; i++) {
279:               for (j = 0; j < perEdge; j++, k++) {
280:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * (perEdge - 1 - i) + (perEdge - 1 - j)) * numComp + c;
281:               }
282:             }
283:             break;
284:           case 3: /* rotate section edge 3 to local edge 0.  This swaps the i and j variables and then reverses the i variable */
285:             for (i = 0, k = 0; i < perEdge; i++) {
286:               for (j = 0; j < perEdge; j++, k++) {
287:                 for (c = 0; c < numComp; c++) perm[k * numComp + c] = (perEdge * j + (perEdge - 1 - i)) * numComp + c;
288:               }
289:             }
290:             break;
291:           default:
292:             break;
293:           }
294:           perms[o - minOrnt] = perm;
295:         }
296:         PetscSectionSymLabelSetStratum(sym, d, numDof * numComp, minOrnt, maxOrnt, PETSC_OWN_POINTER, (const PetscInt **)perms, NULL);
297:       }
298:     }
299:     PetscSectionSetFieldSym(s, f, sym);
300:     PetscSectionSymDestroy(&sym);
301:   }
302:   PetscSectionViewFromOptions(s, NULL, "-section_with_sym_view");
303:   return 0;
304: }

306: int main(int argc, char **argv)
307: {
308:   DM           dm;
309:   PetscSection s;
310:   Vec          u;
311:   AppCtx       user;
312:   PetscInt     dim, size = 0, f;

315:   PetscInitialize(&argc, &argv, NULL, help);
316:   ProcessOptions(PETSC_COMM_WORLD, &user);
317:   DMCreate(PETSC_COMM_WORLD, &dm);
318:   DMSetType(dm, DMPLEX);
319:   DMSetFromOptions(dm);
320:   DMViewFromOptions(dm, NULL, "-dm_view");
321:   DMGetDimension(dm, &dim);
322:   /* Create a section for SEM order k */
323:   {
324:     PetscInt *numDof, d;

326:     PetscMalloc1(user.Nf * (dim + 1), &numDof);
327:     for (f = 0; f < user.Nf; ++f) {
328:       for (d = 0; d <= dim; ++d) numDof[f * (dim + 1) + d] = PetscPowInt(user.k[f] - 1, d) * user.Nc[f];
329:       size += PetscPowInt(user.k[f] + 1, d) * user.Nc[f];
330:     }
331:     DMSetNumFields(dm, user.Nf);
332:     DMPlexCreateSection(dm, NULL, user.Nc, numDof, 0, NULL, NULL, NULL, NULL, &s);
333:     SetSymmetries(dm, s, &user);
334:     PetscFree(numDof);
335:   }
336:   DMSetLocalSection(dm, s);
337:   /* Create spectral ordering and load in data */
338:   DMPlexSetClosurePermutationTensor(dm, PETSC_DETERMINE, NULL);
339:   DMGetLocalVector(dm, &u);
340:   switch (dim) {
341:   case 2:
342:     LoadData2D(dm, 2, 2, size, u, &user);
343:     break;
344:   case 3:
345:     LoadData3D(dm, 2, 2, 2, size, u, &user);
346:     break;
347:   }
348:   /* Remove ordering and check some values */
349:   PetscSectionSetClosurePermutation(s, (PetscObject)dm, dim, NULL);
350:   switch (dim) {
351:   case 2:
352:     CheckPoint(dm, u, 0, &user);
353:     CheckPoint(dm, u, 13, &user);
354:     CheckPoint(dm, u, 15, &user);
355:     CheckPoint(dm, u, 19, &user);
356:     break;
357:   case 3:
358:     CheckPoint(dm, u, 0, &user);
359:     CheckPoint(dm, u, 13, &user);
360:     CheckPoint(dm, u, 15, &user);
361:     CheckPoint(dm, u, 19, &user);
362:     break;
363:   }
364:   /* Recreate spectral ordering and read out data */
365:   DMPlexSetClosurePermutationTensor(dm, PETSC_DETERMINE, s);
366:   switch (dim) {
367:   case 2:
368:     ReadData2D(dm, u, &user);
369:     break;
370:   case 3:
371:     ReadData3D(dm, u, &user);
372:     break;
373:   }
374:   DMRestoreLocalVector(dm, &u);
375:   PetscSectionDestroy(&s);
376:   DMDestroy(&dm);
377:   PetscFree(user.Nc);
378:   PetscFree(user.k);
379:   PetscFinalize();
380:   return 0;
381: }

383: /*TEST

385:   # Spectral ordering 2D 0-5
386:   testset:
387:     args: -dm_plex_simplex 0 -dm_plex_box_faces 2,2

389:     test:
390:       suffix: 0
391:       args: -num_fields 1 -num_components 1 -order 2
392:     test:
393:       suffix: 1
394:       args: -num_fields 1 -num_components 1 -order 3
395:     test:
396:       suffix: 2
397:       args: -num_fields 1 -num_components 1 -order 5
398:     test:
399:       suffix: 3
400:       args: -num_fields 1 -num_components 2 -order 2
401:     test:
402:       suffix: 4
403:       args: -num_fields 2 -num_components 1,1 -order 2,2
404:     test:
405:       suffix: 5
406:       args: -num_fields 2 -num_components 1,2 -order 2,3

408:   # Spectral ordering 3D 6-11
409:   testset:
410:     args: -dm_plex_dim 3 -dm_plex_simplex 0 -dm_plex_box_faces 2,2,2

412:     test:
413:       suffix: 6
414:       args: -num_fields 1 -num_components 1 -order 2
415:     test:
416:       suffix: 7
417:       args: -num_fields 1 -num_components 1 -order 3
418:     test:
419:       suffix: 8
420:       args: -num_fields 1 -num_components 1 -order 5
421:     test:
422:       suffix: 9
423:       args: -num_fields 1 -num_components 2 -order 2
424:     test:
425:       suffix: 10
426:       args: -num_fields 2 -num_components 1,1 -order 2,2
427:     test:
428:       suffix: 11
429:       args: -num_fields 2 -num_components 1,2 -order 2,3

431: TEST*/