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;

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

     22:   PetscOptionsBegin(comm, "", "SEM Problem Options", "DMPLEX");
     23:   PetscOptionsBoundedInt("-num_fields", "The number of fields", "ex6.c", options->Nf, &options->Nf, NULL,0);
     24:   if (options->Nf) {
     25:     len  = options->Nf;
     26:     PetscMalloc1(len, &options->Nc);
     27:     PetscOptionsIntArray("-num_components", "The number of components per field", "ex6.c", options->Nc, &len, &flg);
     29:     len  = options->Nf;
     30:     PetscMalloc1(len, &options->k);
     31:     PetscOptionsIntArray("-order", "The spectral order per field", "ex6.c", options->k, &len, &flg);
     33:   }
     34:   PetscOptionsEnd();
     35:   return 0;
     36: }

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

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

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

     53:         for (kj = 0; kj <= user->k[f]; ++kj) {
     54:           for (ki = 0; ki <= user->k[f]; ++ki) {
     55:             for (c = 0; c < user->Nc[f]; ++c) {
     56:               closure[o++] = ((kj + joff)*(Ni*user->k[f]+1) + ki + ioff)*user->Nc[f]+c;
     57:             }
     58:           }
     59:         }
     60:       }
     61:       DMPlexVecSetClosure(dm, NULL, u, j*Ni+i, closure, INSERT_VALUES);
     62:     }
     63:   }
     64:   PetscFree(closure);
     65:   return 0;
     66: }

     68: static PetscErrorCode LoadData3D(DM dm, PetscInt Ni, PetscInt Nj, PetscInt Nk, PetscInt clSize, Vec u, AppCtx *user)
     69: {
     70:   PetscInt       i, j, k, f, c;
     71:   PetscScalar *closure;

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

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

     84:           for (kk = 0; kk <= user->k[f]; ++kk) {
     85:             for (kj = 0; kj <= user->k[f]; ++kj) {
     86:               for (ki = 0; ki <= user->k[f]; ++ki) {
     87:                 for (c = 0; c < user->Nc[f]; ++c) {
     88:                   closure[o++] = (((kk + koff)*(Nj*user->k[f]+1) + kj + joff)*(Ni*user->k[f]+1) + ki + ioff)*user->Nc[f]+c;
     89:                 }
     90:               }
     91:             }
     92:           }
     93:         }
     94:         DMPlexVecSetClosure(dm, NULL, u, (k*Nj+j)*Ni+i, closure, INSERT_VALUES);
     95:       }
     96:     }
     97:   }
     98:   PetscFree(closure);
     99:   return 0;
    100: }

    102: static PetscErrorCode CheckPoint(DM dm, Vec u, PetscInt point, AppCtx *user)
    103: {
    104:   PetscSection       s;
    105:   PetscScalar        *a;
    106:   const PetscScalar  *array;
    107:   PetscInt           dof, d;

    110:   DMGetLocalSection(dm, &s);
    111:   VecGetArrayRead(u, &array);
    112:   DMPlexPointLocalRead(dm, point, array, &a);
    113:   PetscSectionGetDof(s, point, &dof);
    114:   PetscPrintf(PETSC_COMM_SELF, "Point %D: ", point);
    115:   for (d = 0; d < dof; ++d) {
    116:     if (d > 0) PetscPrintf(PETSC_COMM_SELF, ", ");
    117:     PetscPrintf(PETSC_COMM_SELF, "%2.0f", (double) PetscRealPart(a[d]));
    118:   }
    119:   PetscPrintf(PETSC_COMM_SELF, "\n");
    120:   VecRestoreArrayRead(u, &array);
    121:   return 0;
    122: }

    124: static PetscErrorCode ReadData2D(DM dm, Vec u, AppCtx *user)
    125: {
    126:   PetscInt       cStart, cEnd, cell;

    129:   DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd);
    130:   for (cell = cStart; cell < cEnd; ++cell) {
    131:     PetscScalar *closure = NULL;
    132:     PetscInt     closureSize, ki, kj, f, c, foff = 0;

    134:     DMPlexVecGetClosure(dm, NULL, u, cell, &closureSize, &closure);
    135:     PetscPrintf(PETSC_COMM_SELF, "Cell %D\n", cell);
    136:     for (f = 0; f < user->Nf; ++f) {
    137:       PetscPrintf(PETSC_COMM_SELF, "  Field %D\n", f);
    138:       for (kj = user->k[f]; kj >= 0; --kj) {
    139:         for (ki = 0; ki <= user->k[f]; ++ki) {
    140:           if (ki > 0) PetscPrintf(PETSC_COMM_SELF, "  ");
    141:           for (c = 0; c < user->Nc[f]; ++c) {
    142:             if (c > 0) PetscPrintf(PETSC_COMM_SELF, ",");
    143:             PetscPrintf(PETSC_COMM_SELF, "%2.0f", (double) PetscRealPart(closure[(kj*(user->k[f]+1) + ki)*user->Nc[f]+c + foff]));
    144:           }
    145:         }
    146:         PetscPrintf(PETSC_COMM_SELF, "\n");
    147:       }
    148:       PetscPrintf(PETSC_COMM_SELF, "\n\n");
    149:       foff += PetscSqr(user->k[f]+1);
    150:     }
    151:     DMPlexVecRestoreClosure(dm, NULL, u, cell, &closureSize, &closure);
    152:     PetscPrintf(PETSC_COMM_SELF, "\n\n");
    153:   }
    154:   return 0;
    155: }

    157: static PetscErrorCode ReadData3D(DM dm, Vec u, AppCtx *user)
    158: {
    159:   PetscInt       cStart, cEnd, cell;

    162:   DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd);
    163:   for (cell = cStart; cell < cEnd; ++cell) {
    164:     PetscScalar *closure = NULL;
    165:     PetscInt     closureSize, ki, kj, kk, f, c, foff = 0;

    167:     DMPlexVecGetClosure(dm, NULL, u, cell, &closureSize, &closure);
    168:     PetscPrintf(PETSC_COMM_SELF, "Cell %D\n", cell);
    169:     for (f = 0; f < user->Nf; ++f) {
    170:       PetscPrintf(PETSC_COMM_SELF, "  Field %D\n", f);
    171:       for (kk = user->k[f]; kk >= 0; --kk) {
    172:         for (kj = user->k[f]; kj >= 0; --kj) {
    173:           for (ki = 0; ki <= user->k[f]; ++ki) {
    174:             if (ki > 0) PetscPrintf(PETSC_COMM_SELF, "  ");
    175:             for (c = 0; c < user->Nc[f]; ++c) {
    176:               if (c > 0) PetscPrintf(PETSC_COMM_SELF, ",");
    177:               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]));
    178:             }
    179:           }
    180:           PetscPrintf(PETSC_COMM_SELF, "\n");
    181:         }
    182:         PetscPrintf(PETSC_COMM_SELF, "\n");
    183:       }
    184:       PetscPrintf(PETSC_COMM_SELF, "\n\n");
    185:       foff += PetscSqr(user->k[f]+1);
    186:     }
    187:     DMPlexVecRestoreClosure(dm, NULL, u, cell, &closureSize, &closure);
    188:     PetscPrintf(PETSC_COMM_SELF, "\n\n");
    189:   }
    190:   return 0;
    191: }

    193: static PetscErrorCode SetSymmetries(DM dm, PetscSection s, AppCtx *user)
    194: {
    195:   PetscInt       dim, f, o, i, j, k, c, d;
    196:   DMLabel        depthLabel;

    198:   DMGetDimension(dm, &dim);
    199:   DMGetLabel(dm,"depth",&depthLabel);
    200:   for (f = 0; f < user->Nf; f++) {
    201:     PetscSectionSym sym;

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

    206:     for (d = 0; d <= dim; d++) {
    207:       if (d == 1) {
    208:         PetscInt        numDof  = user->k[f] - 1;
    209:         PetscInt        numComp = user->Nc[f];
    210:         PetscInt        minOrnt = -1;
    211:         PetscInt        maxOrnt = 1;
    212:         PetscInt        **perms;

    214:         PetscCalloc1(maxOrnt - minOrnt,&perms);
    215:         for (o = minOrnt; o < maxOrnt; o++) {
    216:           PetscInt *perm;

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

    237:         PetscCalloc1(maxOrnt-minOrnt,&perms);
    238:         for (o = minOrnt; o < maxOrnt; o++) {
    239:           PetscInt *perm;

    241:           if (!o) continue; /* identity */
    242:           PetscMalloc1(numDof * numComp, &perm);
    243:           /* We want to perm[k] to list which *localArray* position the *sectionArray* position k should go to for the given orientation*/
    244:           switch (o) {
    245:           case 0:
    246:             break; /* identity */
    247:           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 */
    248:             for (i = 0, k = 0; i < perEdge; i++) {
    249:               for (j = 0; j < perEdge; j++, k++) {
    250:                 for (c = 0; c < numComp; c++) {
    251:                   perm[k * numComp + c] = (perEdge * j + i) * numComp + c;
    252:                 }
    253:               }
    254:             }
    255:             break;
    256:           case -1: /* flip along (-1, 0)--( 1, 0), which swaps edges 0 and 2.  This reverses the i variable */
    257:             for (i = 0, k = 0; i < perEdge; i++) {
    258:               for (j = 0; j < perEdge; j++, k++) {
    259:                 for (c = 0; c < numComp; c++) {
    260:                   perm[k * numComp + c] = (perEdge * (perEdge - 1 - i) + j) * numComp + c;
    261:                 }
    262:               }
    263:             }
    264:             break;
    265:           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 */
    266:             for (i = 0, k = 0; i < perEdge; i++) {
    267:               for (j = 0; j < perEdge; j++, k++) {
    268:                 for (c = 0; c < numComp; c++) {
    269:                   perm[k * numComp + c] = (perEdge * (perEdge - 1 - j) + (perEdge - 1 - i)) * numComp + c;
    270:                 }
    271:               }
    272:             }
    273:             break;
    274:           case -3: /* flip along ( 0,-1)--( 0, 1), which swaps edges 3 and 1.  This reverses the j variable */
    275:             for (i = 0, k = 0; i < perEdge; i++) {
    276:               for (j = 0; j < perEdge; j++, k++) {
    277:                 for (c = 0; c < numComp; c++) {
    278:                   perm[k * numComp + c] = (perEdge * i + (perEdge - 1 - j)) * numComp + c;
    279:                 }
    280:               }
    281:             }
    282:             break;
    283:           case  1: /* rotate section edge 1 to local edge 0.  This swaps the i and j variables and then reverses the j variable */
    284:             for (i = 0, k = 0; i < perEdge; i++) {
    285:               for (j = 0; j < perEdge; j++, k++) {
    286:                 for (c = 0; c < numComp; c++) {
    287:                   perm[k * numComp + c] = (perEdge * (perEdge - 1 - j) + i) * numComp + c;
    288:                 }
    289:               }
    290:             }
    291:             break;
    292:           case  2: /* rotate section edge 2 to local edge 0.  This reverse both i and j variables */
    293:             for (i = 0, k = 0; i < perEdge; i++) {
    294:               for (j = 0; j < perEdge; j++, k++) {
    295:                 for (c = 0; c < numComp; c++) {
    296:                   perm[k * numComp + c] = (perEdge * (perEdge - 1 - i) + (perEdge - 1 - j)) * numComp + c;
    297:                 }
    298:               }
    299:             }
    300:             break;
    301:           case  3: /* rotate section edge 3 to local edge 0.  This swaps the i and j variables and then reverses the i variable */
    302:             for (i = 0, k = 0; i < perEdge; i++) {
    303:               for (j = 0; j < perEdge; j++, k++) {
    304:                 for (c = 0; c < numComp; c++) {
    305:                   perm[k * numComp + c] = (perEdge * j + (perEdge - 1 - i)) * numComp + c;
    306:                 }
    307:               }
    308:             }
    309:             break;
    310:           default:
    311:             break;
    312:           }
    313:           perms[o - minOrnt] = perm;
    314:         }
    315:         PetscSectionSymLabelSetStratum(sym,d,numDof*numComp,minOrnt,maxOrnt,PETSC_OWN_POINTER,(const PetscInt **) perms,NULL);
    316:       }
    317:     }
    318:     PetscSectionSetFieldSym(s,f,sym);
    319:     PetscSectionSymDestroy(&sym);
    320:   }
    321:   PetscSectionViewFromOptions(s,NULL,"-section_with_sym_view");
    322:   return 0;
    323: }

    325: int main(int argc, char **argv)
    326: {
    327:   DM             dm;
    328:   PetscSection   s;
    329:   Vec            u;
    330:   AppCtx         user;
    331:   PetscInt       dim, size = 0, f;

    333:   PetscInitialize(&argc, &argv, NULL,help);
    334:   ProcessOptions(PETSC_COMM_WORLD, &user);
    335:   DMCreate(PETSC_COMM_WORLD, &dm);
    336:   DMSetType(dm, DMPLEX);
    337:   DMSetFromOptions(dm);
    338:   DMViewFromOptions(dm, NULL, "-dm_view");
    339:   DMGetDimension(dm, &dim);
    340:   /* Create a section for SEM order k */
    341:   {
    342:     PetscInt *numDof, d;

    344:     PetscMalloc1(user.Nf*(dim+1), &numDof);
    345:     for (f = 0; f < user.Nf; ++f) {
    346:       for (d = 0; d <= dim; ++d) numDof[f*(dim+1)+d] = PetscPowInt(user.k[f]-1, d)*user.Nc[f];
    347:       size += PetscPowInt(user.k[f]+1, d)*user.Nc[f];
    348:     }
    349:     DMSetNumFields(dm, user.Nf);
    350:     DMPlexCreateSection(dm, NULL, user.Nc, numDof, 0, NULL, NULL, NULL, NULL, &s);
    351:     SetSymmetries(dm, s, &user);
    352:     PetscFree(numDof);
    353:   }
    354:   DMSetLocalSection(dm, s);
    355:   /* Create spectral ordering and load in data */
    356:   DMPlexSetClosurePermutationTensor(dm, PETSC_DETERMINE, NULL);
    357:   DMGetLocalVector(dm, &u);
    358:   switch (dim) {
    359:   case 2: LoadData2D(dm, 2, 2, size, u, &user);break;
    360:   case 3: LoadData3D(dm, 2, 2, 2, size, u, &user);break;
    361:   }
    362:   /* Remove ordering and check some values */
    363:   PetscSectionSetClosurePermutation(s, (PetscObject) dm, dim, NULL);
    364:   switch (dim) {
    365:   case 2:
    366:     CheckPoint(dm, u,  0, &user);
    367:     CheckPoint(dm, u, 13, &user);
    368:     CheckPoint(dm, u, 15, &user);
    369:     CheckPoint(dm, u, 19, &user);
    370:     break;
    371:   case 3:
    372:     CheckPoint(dm, u,  0, &user);
    373:     CheckPoint(dm, u, 13, &user);
    374:     CheckPoint(dm, u, 15, &user);
    375:     CheckPoint(dm, u, 19, &user);
    376:     break;
    377:   }
    378:   /* Recreate spectral ordering and read out data */
    379:   DMPlexSetClosurePermutationTensor(dm, PETSC_DETERMINE, s);
    380:   switch (dim) {
    381:   case 2: ReadData2D(dm, u, &user);break;
    382:   case 3: ReadData3D(dm, u, &user);break;
    383:   }
    384:   DMRestoreLocalVector(dm, &u);
    385:   PetscSectionDestroy(&s);
    386:   DMDestroy(&dm);
    387:   PetscFree(user.Nc);
    388:   PetscFree(user.k);
    389:   PetscFinalize();
    390:   return 0;
    391: }

    393: /*TEST

    395:   # Spectral ordering 2D 0-5
    396:   testset:
    397:     args: -dm_plex_simplex 0 -dm_plex_box_faces 2,2

    399:     test:
    400:       suffix: 0
    401:       args: -num_fields 1 -num_components 1 -order 2
    402:     test:
    403:       suffix: 1
    404:       args: -num_fields 1 -num_components 1 -order 3
    405:     test:
    406:       suffix: 2
    407:       args: -num_fields 1 -num_components 1 -order 5
    408:     test:
    409:       suffix: 3
    410:       args: -num_fields 1 -num_components 2 -order 2
    411:     test:
    412:       suffix: 4
    413:       args: -num_fields 2 -num_components 1,1 -order 2,2
    414:     test:
    415:       suffix: 5
    416:       args: -num_fields 2 -num_components 1,2 -order 2,3

    418:   # Spectral ordering 3D 6-11
    419:   testset:
    420:     args: -dm_plex_dim 3 -dm_plex_simplex 0 -dm_plex_box_faces 2,2,2

    422:     test:
    423:       suffix: 6
    424:       args: -num_fields 1 -num_components 1 -order 2
    425:     test:
    426:       suffix: 7
    427:       args: -num_fields 1 -num_components 1 -order 3
    428:     test:
    429:       suffix: 8
    430:       args: -num_fields 1 -num_components 1 -order 5
    431:     test:
    432:       suffix: 9
    433:       args: -num_fields 1 -num_components 2 -order 2
    434:     test:
    435:       suffix: 10
    436:       args: -num_fields 2 -num_components 1,1 -order 2,2
    437:     test:
    438:       suffix: 11
    439:       args: -num_fields 2 -num_components 1,2 -order 2,3

    441: TEST*/