Actual source code: ex2.c

petsc-3.14.6 2021-03-30
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  1: static char help[] = "Tests L2 projection with DMSwarm using delta function particles.\n";

  3: #include <petscdmplex.h>
  4: #include <petscfe.h>
  5: #include <petscdmswarm.h>
  6: #include <petscds.h>
  7: #include <petscksp.h>
  8: #include <petsc/private/petscfeimpl.h>
  9: typedef struct {
 10:   char      meshFilename[PETSC_MAX_PATH_LEN]; /* Name of the mesh filename if any */
 11:   PetscReal L[3];                             /* Dimensions of the mesh bounding box */
 12:   PetscInt  particlesPerCell;                 /* The number of partices per cell */
 13:   PetscReal particleRelDx;                    /* Relative particle position perturbation compared to average cell diameter h */
 14:   PetscReal meshRelDx;                        /* Relative vertex position perturbation compared to average cell diameter h */
 15:   PetscInt  k;                                /* Mode number for test function */
 16:   PetscReal momentTol;                        /* Tolerance for checking moment conservation */
 17:   PetscBool useBlockDiagPrec;                 /* Use the block diagonal of the normal equations as a preconditioner */
 18:   PetscErrorCode (*func)(PetscInt, PetscReal, const PetscReal [], PetscInt, PetscScalar *, void *);
 19: } AppCtx;

 21: /* const char *const ex2FunctionTypes[] = {"linear","x2_x4","sin","ex2FunctionTypes","EX2_FUNCTION_",0}; */

 23: static PetscErrorCode linear(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nc, PetscScalar *u, void *a_ctx)
 24: {
 25:   AppCtx  *ctx = (AppCtx *) a_ctx;
 26:   PetscInt d;

 28:   u[0] = 0.0;
 29:   for (d = 0; d < dim; ++d) u[0] += x[d]/(ctx->L[d]);
 30:   return 0;
 31: }

 33: static PetscErrorCode x2_x4(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nc, PetscScalar *u, void *a_ctx)
 34: {
 35:   AppCtx  *ctx = (AppCtx *) a_ctx;
 36:   PetscInt d;

 38:   u[0] = 1;
 39:   for (d = 0; d < dim; ++d) u[0] *= PetscSqr(x[d])*PetscSqr(ctx->L[d]) - PetscPowRealInt(x[d], 4);
 40:   return 0;
 41: }

 43: static PetscErrorCode sinx(PetscInt dim, PetscReal time, const PetscReal x[], PetscInt Nc, PetscScalar *u, void *a_ctx)
 44: {
 45:   AppCtx *ctx = (AppCtx *) a_ctx;

 47:   u[0] = PetscSinScalar(2*PETSC_PI*ctx->k*x[0]/(ctx->L[0]));
 48:   return 0;
 49: }

 51: static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
 52: {
 53:   char           fstring[PETSC_MAX_PATH_LEN] = "linear";
 54:   PetscBool      flag;

 58:   options->particlesPerCell = 1;
 59:   options->k                = 1;
 60:   options->particleRelDx    = 1.e-20;
 61:   options->meshRelDx        = 1.e-20;
 62:   options->momentTol        = 100.*PETSC_MACHINE_EPSILON;
 63:   options->useBlockDiagPrec = PETSC_FALSE;
 64:   PetscStrcpy(options->meshFilename, "");

 66:   PetscOptionsBegin(comm, "", "L2 Projection Options", "DMPLEX");
 67:   PetscOptionsString("-mesh", "Name of the mesh filename if any", "ex2.c", options->meshFilename, options->meshFilename, sizeof(options->meshFilename), NULL);
 68:   PetscOptionsInt("-k", "Mode number of test", "ex2.c", options->k, &options->k, NULL);
 69:   PetscOptionsInt("-particlesPerCell", "Number of particles per cell", "ex2.c", options->particlesPerCell, &options->particlesPerCell, NULL);
 70:   PetscOptionsReal("-particle_perturbation", "Relative perturbation of particles (0,1)", "ex2.c", options->particleRelDx, &options->particleRelDx, NULL);
 71:   PetscOptionsReal("-mesh_perturbation", "Relative perturbation of mesh points (0,1)", "ex2.c", options->meshRelDx, &options->meshRelDx, NULL);
 72:   PetscOptionsString("-function", "Name of test function", "ex2.c", fstring, fstring, sizeof(fstring), NULL);
 73:   PetscStrcmp(fstring, "linear", &flag);
 74:   if (flag) {
 75:     options->func = linear;
 76:   } else {
 77:     PetscStrcmp(fstring, "sin", &flag);
 78:     if (flag) {
 79:       options->func = sinx;
 80:     } else {
 81:       PetscStrcmp(fstring, "x2_x4", &flag);
 82:       options->func = x2_x4;
 83:       if (!flag) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Unknown function %s",fstring);
 84:     }
 85:   }
 86:   PetscOptionsReal("-moment_tol", "Tolerance for moment checks", "ex2.c", options->momentTol, &options->momentTol, NULL);
 87:   PetscOptionsBool("-block_diag_prec", "Use the block diagonal of the normal equations to precondition the particle projection", "ex2.c", options->useBlockDiagPrec, &options->useBlockDiagPrec, NULL);
 88:   PetscOptionsEnd();

 90:   return(0);
 91: }

 93: static PetscErrorCode PerturbVertices(DM dm, AppCtx *user)
 94: {
 95:   PetscRandom    rnd;
 96:   PetscReal      interval = user->meshRelDx;
 97:   Vec            coordinates;
 98:   PetscScalar   *coords;
 99:   PetscReal     *hh, low[3], high[3];
100:   PetscInt       d, cdim, cEnd, N, p, bs;

104:   DMGetBoundingBox(dm, low, high);
105:   DMPlexGetHeightStratum(dm, 0, NULL, &cEnd);
106:   PetscRandomCreate(PetscObjectComm((PetscObject) dm), &rnd);
107:   PetscRandomSetInterval(rnd, -interval, interval);
108:   PetscRandomSetFromOptions(rnd);
109:   DMGetCoordinatesLocal(dm, &coordinates);
110:   DMGetCoordinateDim(dm, &cdim);
111:   PetscCalloc1(cdim,&hh);
112:   for (d = 0; d < cdim; ++d) hh[d] = (user->L[d])/PetscPowReal(cEnd, 1./cdim);
113:   VecGetLocalSize(coordinates, &N);
114:   VecGetBlockSize(coordinates, &bs);
115:   if (bs != cdim) SETERRQ2(PetscObjectComm((PetscObject) dm), PETSC_ERR_ARG_SIZ, "Coordinate vector has wrong block size %D != %D", bs, cdim);
116:   VecGetArray(coordinates, &coords);
117:   for (p = 0; p < N; p += cdim) {
118:     PetscScalar *coord = &coords[p], value;

120:     for (d = 0; d < cdim; ++d) {
121:       PetscRandomGetValue(rnd, &value);
122:       coord[d] = PetscMax(low[d], PetscMin(high[d], PetscRealPart(coord[d] + value*hh[d])));
123:     }
124:   }
125:   VecRestoreArray(coordinates, &coords);
126:   PetscRandomDestroy(&rnd);
127:   PetscFree(hh);
128:   return(0);
129: }

131: static PetscErrorCode CreateMesh(MPI_Comm comm, DM *dm, AppCtx *user)
132: {
133:   PetscReal      low[3], high[3];
134:   PetscInt       cdim, d;
135:   PetscBool      flg;

139:   PetscStrcmp(user->meshFilename, "", &flg);
140:   if (flg) {
141:     DMPlexCreateBoxMesh(comm, 2, PETSC_TRUE, NULL, NULL, NULL, NULL, PETSC_TRUE, dm);
142:   } else {
143:     DMPlexCreateFromFile(comm, user->meshFilename, PETSC_TRUE, dm);
144:   }
145:   DMGetCoordinateDim(*dm, &cdim);
146:   DMGetBoundingBox(*dm, low, high);
147:   for (d = 0; d < cdim; ++d) user->L[d] = high[d] - low[d];
148:   {
149:     DM distributedMesh = NULL;

151:     DMPlexDistribute(*dm, 0, NULL, &distributedMesh);
152:     if (distributedMesh) {
153:       DMDestroy(dm);
154:       *dm  = distributedMesh;
155:     }
156:   }
157:   DMLocalizeCoordinates(*dm); /* needed for periodic */
158:   DMSetFromOptions(*dm);
159:   PerturbVertices(*dm, user);
160:   PetscObjectSetName((PetscObject) *dm, "Mesh");
161:   DMViewFromOptions(*dm, NULL, "-dm_view");
162:   return(0);
163: }

165: static void identity(PetscInt dim, PetscInt Nf, PetscInt NfAux,
166:                      const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
167:                      const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
168:                      PetscReal t, PetscReal u_tShift, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar g0[])
169: {
170:   g0[0] = 1.0;
171: }

173: static PetscErrorCode CreateFEM(DM dm, AppCtx *user)
174: {
175:   PetscFE        fe;
176:   PetscDS        ds;
177:   DMPolytopeType ct;
178:   PetscBool      simplex;
179:   PetscInt       dim, cStart;

183:   DMGetDimension(dm, &dim);
184:   DMPlexGetHeightStratum(dm, 0, &cStart, NULL);
185:   DMPlexGetCellType(dm, cStart, &ct);
186:   simplex = DMPolytopeTypeGetNumVertices(ct) == DMPolytopeTypeGetDim(ct)+1 ? PETSC_TRUE : PETSC_FALSE;
187:   PetscFECreateDefault(PetscObjectComm((PetscObject) dm), dim, 1, simplex, NULL, -1, &fe);
188:   PetscObjectSetName((PetscObject) fe, "fe");
189:   DMSetField(dm, 0, NULL, (PetscObject) fe);
190:   DMCreateDS(dm);
191:   PetscFEDestroy(&fe);
192:   /* Setup to form mass matrix */
193:   DMGetDS(dm, &ds);
194:   PetscDSSetJacobian(ds, 0, 0, identity, NULL, NULL, NULL);
195:   return(0);
196: }

198: static PetscErrorCode CreateParticles(DM dm, DM *sw, AppCtx *user)
199: {
200:   PetscRandom    rnd, rndp;
201:   PetscReal      interval = user->particleRelDx;
202:   DMPolytopeType ct;
203:   PetscBool      simplex;
204:   PetscScalar    value, *vals;
205:   PetscReal     *centroid, *coords, *xi0, *v0, *J, *invJ, detJ;
206:   PetscInt      *cellid;
207:   PetscInt       Ncell, Np = user->particlesPerCell, p, cStart, c, dim, d;

211:   DMGetDimension(dm, &dim);
212:   DMPlexGetHeightStratum(dm, 0, &cStart, NULL);
213:   DMPlexGetCellType(dm, cStart, &ct);
214:   simplex = DMPolytopeTypeGetNumVertices(ct) == DMPolytopeTypeGetDim(ct)+1 ? PETSC_TRUE : PETSC_FALSE;
215:   DMCreate(PetscObjectComm((PetscObject) dm), sw);
216:   DMSetType(*sw, DMSWARM);
217:   DMSetDimension(*sw, dim);

219:   PetscRandomCreate(PetscObjectComm((PetscObject) dm), &rnd);
220:   PetscRandomSetInterval(rnd, -1.0, 1.0);
221:   PetscRandomSetFromOptions(rnd);
222:   PetscRandomCreate(PetscObjectComm((PetscObject) dm), &rndp);
223:   PetscRandomSetInterval(rndp, -interval, interval);
224:   PetscRandomSetFromOptions(rndp);

226:   DMSwarmSetType(*sw, DMSWARM_PIC);
227:   DMSwarmSetCellDM(*sw, dm);
228:   DMSwarmRegisterPetscDatatypeField(*sw, "w_q", 1, PETSC_SCALAR);
229:   DMSwarmFinalizeFieldRegister(*sw);
230:   DMPlexGetHeightStratum(dm, 0, NULL, &Ncell);
231:   DMSwarmSetLocalSizes(*sw, Ncell * Np, 0);
232:   DMSetFromOptions(*sw);
233:   DMSwarmGetField(*sw, DMSwarmPICField_coor, NULL, NULL, (void **) &coords);
234:   DMSwarmGetField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **) &cellid);
235:   DMSwarmGetField(*sw, "w_q", NULL, NULL, (void **) &vals);

237:   PetscMalloc5(dim, &centroid, dim, &xi0, dim, &v0, dim*dim, &J, dim*dim, &invJ);
238:   for (c = 0; c < Ncell; ++c) {
239:     if (Np == 1) {
240:       DMPlexComputeCellGeometryFVM(dm, c, NULL, centroid, NULL);
241:       cellid[c] = c;
242:       for (d = 0; d < dim; ++d) coords[c*dim+d] = centroid[d];
243:     } else {
244:       DMPlexComputeCellGeometryFEM(dm, c, NULL, v0, J, invJ, &detJ); /* affine */
245:       for (d = 0; d < dim; ++d) xi0[d] = -1.0;
246:       for (p = 0; p < Np; ++p) {
247:         const PetscInt n   = c*Np + p;
248:         PetscReal      sum = 0.0, refcoords[3];

250:         cellid[n] = c;
251:         for (d = 0; d < dim; ++d) {PetscRandomGetValue(rnd, &value); refcoords[d] = PetscRealPart(value); sum += refcoords[d];}
252:         if (simplex && sum > 0.0) for (d = 0; d < dim; ++d) refcoords[d] -= PetscSqrtReal(dim)*sum;
253:         CoordinatesRefToReal(dim, dim, xi0, v0, J, refcoords, &coords[n*dim]);
254:       }
255:     }
256:   }
257:   PetscFree5(centroid, xi0, v0, J, invJ);
258:   for (c = 0; c < Ncell; ++c) {
259:     for (p = 0; p < Np; ++p) {
260:       const PetscInt n = c*Np + p;

262:       for (d = 0; d < dim; ++d) {PetscRandomGetValue(rndp, &value); coords[n*dim+d] += PetscRealPart(value);}
263:       user->func(dim, 0.0, &coords[n*dim], 1, &vals[c], user);
264:     }
265:   }
266:   DMSwarmRestoreField(*sw, DMSwarmPICField_coor, NULL, NULL, (void **) &coords);
267:   DMSwarmRestoreField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **) &cellid);
268:   DMSwarmRestoreField(*sw, "w_q", NULL, NULL, (void **) &vals);
269:   PetscRandomDestroy(&rnd);
270:   PetscRandomDestroy(&rndp);
271:   PetscObjectSetName((PetscObject) *sw, "Particles");
272:   DMViewFromOptions(*sw, NULL, "-sw_view");
273:   return(0);
274: }

276: static PetscErrorCode computeParticleMoments(DM sw, PetscReal moments[3], AppCtx *user)
277: {
278:   DM                 dm;
279:   const PetscReal   *coords;
280:   const PetscScalar *w;
281:   PetscReal          mom[3] = {0.0, 0.0, 0.0};
282:   PetscInt           cell, cStart, cEnd, dim;
283:   PetscErrorCode     ierr;

286:   DMGetDimension(sw, &dim);
287:   DMSwarmGetCellDM(sw, &dm);
288:   DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd);
289:   DMSwarmSortGetAccess(sw);
290:   DMSwarmGetField(sw, DMSwarmPICField_coor, NULL, NULL, (void **) &coords);
291:   DMSwarmGetField(sw, "w_q", NULL, NULL, (void **) &w);
292:   for (cell = cStart; cell < cEnd; ++cell) {
293:     PetscInt *pidx;
294:     PetscInt  Np, p, d;

296:     DMSwarmSortGetPointsPerCell(sw, cell, &Np, &pidx);
297:     for (p = 0; p < Np; ++p) {
298:       const PetscInt   idx = pidx[p];
299:       const PetscReal *c   = &coords[idx*dim];

301:       mom[0] += PetscRealPart(w[idx]);
302:       mom[1] += PetscRealPart(w[idx]) * c[0];
303:       for (d = 0; d < dim; ++d) mom[2] += PetscRealPart(w[idx]) * c[d]*c[d];
304:     }
305:     PetscFree(pidx);
306:   }
307:   DMSwarmRestoreField(sw, DMSwarmPICField_coor, NULL, NULL, (void **) &coords);
308:   DMSwarmRestoreField(sw, "w_q", NULL, NULL, (void **) &w);
309:   DMSwarmSortRestoreAccess(sw);
310:   MPI_Allreduce(mom, moments, 3, MPIU_REAL, MPI_SUM, PetscObjectComm((PetscObject) sw));
311:   return(0);
312: }

314: static void f0_1(PetscInt dim, PetscInt Nf, PetscInt NfAux,
315:                  const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
316:                  const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
317:                  PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
318: {
319:   f0[0] = u[0];
320: }

322: static void f0_x(PetscInt dim, PetscInt Nf, PetscInt NfAux,
323:                     const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
324:                     const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
325:                     PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
326: {
327:   f0[0] = x[0]*u[0];
328: }

330: static void f0_r2(PetscInt dim, PetscInt Nf, PetscInt NfAux,
331:                   const PetscInt uOff[], const PetscInt uOff_x[], const PetscScalar u[], const PetscScalar u_t[], const PetscScalar u_x[],
332:                   const PetscInt aOff[], const PetscInt aOff_x[], const PetscScalar a[], const PetscScalar a_t[], const PetscScalar a_x[],
333:                   PetscReal t, const PetscReal x[], PetscInt numConstants, const PetscScalar constants[], PetscScalar f0[])
334: {
335:   PetscInt d;

337:   f0[0] = 0.0;
338:   for (d = 0; d < dim; ++d) f0[0] += PetscSqr(x[d])*u[0];
339: }

341: static PetscErrorCode computeFEMMoments(DM dm, Vec u, PetscReal moments[3], AppCtx *user)
342: {
343:   PetscDS        prob;
345:   PetscScalar    mom;

348:   DMGetDS(dm, &prob);
349:   PetscDSSetObjective(prob, 0, &f0_1);
350:   DMPlexComputeIntegralFEM(dm, u, &mom, user);
351:   moments[0] = PetscRealPart(mom);
352:   PetscDSSetObjective(prob, 0, &f0_x);
353:   DMPlexComputeIntegralFEM(dm, u, &mom, user);
354:   moments[1] = PetscRealPart(mom);
355:   PetscDSSetObjective(prob, 0, &f0_r2);
356:   DMPlexComputeIntegralFEM(dm, u, &mom, user);
357:   moments[2] = PetscRealPart(mom);
358:   return(0);
359: }

361: static PetscErrorCode TestL2ProjectionParticlesToField(DM dm, DM sw, AppCtx *user)
362: {
363:   MPI_Comm       comm;
364:   KSP            ksp;
365:   Mat            M;            /* FEM mass matrix */
366:   Mat            M_p;          /* Particle mass matrix */
367:   Vec            f, rhs, fhat; /* Particle field f, \int phi_i f, FEM field */
368:   PetscReal      pmoments[3];  /* \int f, \int x f, \int r^2 f */
369:   PetscReal      fmoments[3];  /* \int \hat f, \int x \hat f, \int r^2 \hat f */
370:   PetscInt       m;

374:   PetscObjectGetComm((PetscObject) dm, &comm);
375:   KSPCreate(comm, &ksp);
376:   KSPSetOptionsPrefix(ksp, "ptof_");
377:   DMGetGlobalVector(dm, &fhat);
378:   DMGetGlobalVector(dm, &rhs);

380:   DMCreateMassMatrix(sw, dm, &M_p);
381:   MatViewFromOptions(M_p, NULL, "-M_p_view");

383:   /* make particle weight vector */
384:   DMSwarmCreateGlobalVectorFromField(sw, "w_q", &f);

386:   /* create matrix RHS vector */
387:   MatMultTranspose(M_p, f, rhs);
388:   DMSwarmDestroyGlobalVectorFromField(sw, "w_q", &f);
389:   PetscObjectSetName((PetscObject) rhs,"rhs");
390:   VecViewFromOptions(rhs, NULL, "-rhs_view");

392:   DMCreateMatrix(dm, &M);
393:   DMPlexSNESComputeJacobianFEM(dm, fhat, M, M, user);
394:   MatViewFromOptions(M, NULL, "-M_view");
395:   KSPSetOperators(ksp, M, M);
396:   KSPSetFromOptions(ksp);
397:   KSPSolve(ksp, rhs, fhat);
398:   PetscObjectSetName((PetscObject) fhat,"fhat");
399:   VecViewFromOptions(fhat, NULL, "-fhat_view");

401:   /* Check moments of field */
402:   computeParticleMoments(sw, pmoments, user);
403:   computeFEMMoments(dm, fhat, fmoments, user);
404:   PetscPrintf(comm, "L2 projection mass: %20.10e, x-momentum: %20.10e, energy: %20.10e.\n", fmoments[0], fmoments[1], fmoments[2]);
405:   for (m = 0; m < 3; ++m) {
406:     if (PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]) > user->momentTol) SETERRQ3(comm, PETSC_ERR_ARG_WRONG, "Moment %D error too large %g > %g", m, PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]), user->momentTol);
407:   }

409:   KSPDestroy(&ksp);
410:   MatDestroy(&M);
411:   MatDestroy(&M_p);
412:   DMRestoreGlobalVector(dm, &fhat);
413:   DMRestoreGlobalVector(dm, &rhs);

415:   return(0);
416: }


419: static PetscErrorCode TestL2ProjectionFieldToParticles(DM dm, DM sw, AppCtx *user)
420: {

422:   MPI_Comm       comm;
423:   KSP            ksp;
424:   Mat            M;            /* FEM mass matrix */
425:   Mat            M_p, PM_p;    /* Particle mass matrix M_p, and the preconditioning matrix, e.g. M_p M^T_p */
426:   Vec            f, rhs, fhat; /* Particle field f, \int phi_i fhat, FEM field */
427:   PetscReal      pmoments[3];  /* \int f, \int x f, \int r^2 f */
428:   PetscReal      fmoments[3];  /* \int \hat f, \int x \hat f, \int r^2 \hat f */
429:   PetscInt       m;

433:   PetscObjectGetComm((PetscObject) dm, &comm);

435:   KSPCreate(comm, &ksp);
436:   KSPSetOptionsPrefix(ksp, "ftop_");
437:   KSPSetFromOptions(ksp);

439:   DMGetGlobalVector(dm, &fhat);
440:   DMGetGlobalVector(dm, &rhs);

442:   DMCreateMassMatrix(sw, dm, &M_p);
443:   MatViewFromOptions(M_p, NULL, "-M_p_view");

445:   /* make particle weight vector */
446:   DMSwarmCreateGlobalVectorFromField(sw, "w_q", &f);

448:   /* create matrix RHS vector, in this case the FEM field fhat with the coefficients vector #alpha */
449:   PetscObjectSetName((PetscObject) rhs,"rhs");
450:   VecViewFromOptions(rhs, NULL, "-rhs_view");
451:   DMCreateMatrix(dm, &M);
452:   DMPlexSNESComputeJacobianFEM(dm, fhat, M, M, user);
453:   MatViewFromOptions(M, NULL, "-M_view");
454:   MatMultTranspose(M, fhat, rhs);
455:   if (user->useBlockDiagPrec) {DMSwarmCreateMassMatrixSquare(sw, dm, &PM_p);}
456:   else                        {PetscObjectReference((PetscObject) M_p); PM_p = M_p;}

458:   KSPSetOperators(ksp, M_p, PM_p);
459:   KSPSolveTranspose(ksp, rhs, f);
460:   PetscObjectSetName((PetscObject) fhat,"fhat");
461:   VecViewFromOptions(fhat, NULL, "-fhat_view");

463:   DMSwarmDestroyGlobalVectorFromField(sw, "w_q", &f);

465:   /* Check moments */
466:   computeParticleMoments(sw, pmoments, user);
467:   computeFEMMoments(dm, fhat, fmoments, user);
468:   PetscPrintf(comm, "L2 projection mass: %20.10e, x-momentum: %20.10e, energy: %20.10e.\n", fmoments[0], fmoments[1], fmoments[2]);
469:   for (m = 0; m < 3; ++m) {
470:     if (PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]) > user->momentTol) SETERRQ3(comm, PETSC_ERR_ARG_WRONG, "Moment %D error too large %g > %g", m, PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]), user->momentTol);
471:   }
472:   KSPDestroy(&ksp);
473:   MatDestroy(&M);
474:   MatDestroy(&M_p);
475:   MatDestroy(&PM_p);
476:   DMRestoreGlobalVector(dm, &fhat);
477:   DMRestoreGlobalVector(dm, &rhs);
478:   return(0);
479: }

481: /* Interpolate the gradient of an FEM (FVM) field. Code repurposed from DMPlexComputeGradientClementInterpolant */
482: static PetscErrorCode InterpolateGradient(DM dm, Vec locX, Vec locC){

484:   DM_Plex         *mesh  = (DM_Plex *) dm->data;
485:   PetscInt         debug = mesh->printFEM;
486:   DM               dmC;
487:   PetscSection     section;
488:   PetscQuadrature  quad = NULL;
489:   PetscScalar     *interpolant, *gradsum;
490:   PetscFEGeom      fegeom;
491:   PetscReal       *coords;
492:   const PetscReal *quadPoints, *quadWeights;
493:   PetscInt         dim, coordDim, numFields, numComponents = 0, qNc, Nq, cStart, cEnd, vStart, vEnd, v, field, fieldOffset;
494:   PetscErrorCode   ierr;

497:   VecGetDM(locC, &dmC);
498:   VecSet(locC, 0.0);
499:   DMGetDimension(dm, &dim);
500:   DMGetCoordinateDim(dm, &coordDim);
501:   fegeom.dimEmbed = coordDim;
502:   DMGetLocalSection(dm, &section);
503:   PetscSectionGetNumFields(section, &numFields);
504:   for (field = 0; field < numFields; ++field) {
505:     PetscObject  obj;
506:     PetscClassId id;
507:     PetscInt     Nc;

509:     DMGetField(dm, field, NULL, &obj);
510:     PetscObjectGetClassId(obj, &id);
511:     if (id == PETSCFE_CLASSID) {
512:       PetscFE fe = (PetscFE) obj;

514:       PetscFEGetQuadrature(fe, &quad);
515:       PetscFEGetNumComponents(fe, &Nc);
516:     } else if (id == PETSCFV_CLASSID) {
517:       PetscFV fv = (PetscFV) obj;

519:       PetscFVGetQuadrature(fv, &quad);
520:       PetscFVGetNumComponents(fv, &Nc);
521:     } else SETERRQ1(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Unknown discretization type for field %d", field);
522:     numComponents += Nc;
523:   }
524:   PetscQuadratureGetData(quad, NULL, &qNc, &Nq, &quadPoints, &quadWeights);
525:   if ((qNc != 1) && (qNc != numComponents)) SETERRQ2(PetscObjectComm((PetscObject) dm), PETSC_ERR_ARG_SIZ, "Quadrature components %D != %D field components", qNc, numComponents);
526:   PetscMalloc6(coordDim*numComponents*2,&gradsum,coordDim*numComponents,&interpolant,coordDim*Nq,&coords,Nq,&fegeom.detJ,coordDim*coordDim*Nq,&fegeom.J,coordDim*coordDim*Nq,&fegeom.invJ);
527:   DMPlexGetDepthStratum(dm, 0, &vStart, &vEnd);
528:   DMPlexGetSimplexOrBoxCells(dm, 0, &cStart, &cEnd);
529:   for (v = vStart; v < vEnd; ++v) {
530:     PetscInt   *star = NULL;
531:     PetscInt    starSize, st, d, fc;

533:     PetscArrayzero(gradsum, coordDim*numComponents);
534:     DMPlexGetTransitiveClosure(dm, v, PETSC_FALSE, &starSize, &star);
535:     for (st = 0; st < starSize*2; st += 2) {
536:       const PetscInt cell = star[st];
537:       PetscScalar   *grad = &gradsum[coordDim*numComponents];
538:       PetscScalar   *x    = NULL;

540:       if ((cell < cStart) || (cell >= cEnd)) continue;
541:       DMPlexComputeCellGeometryFEM(dm, cell, quad, coords, fegeom.J, fegeom.invJ, fegeom.detJ);
542:       DMPlexVecGetClosure(dm, NULL, locX, cell, NULL, &x);
543:       for (field = 0, fieldOffset = 0; field < numFields; ++field) {
544:         PetscObject  obj;
545:         PetscClassId id;
546:         PetscInt     Nb, Nc, q, qc = 0;

548:         PetscArrayzero(grad, coordDim*numComponents);
549:         DMGetField(dm, field, NULL, &obj);
550:         PetscObjectGetClassId(obj, &id);
551:         if (id == PETSCFE_CLASSID)      {PetscFEGetNumComponents((PetscFE) obj, &Nc);PetscFEGetDimension((PetscFE) obj, &Nb);}
552:         else if (id == PETSCFV_CLASSID) {PetscFVGetNumComponents((PetscFV) obj, &Nc);Nb = 1;}
553:         else SETERRQ1(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Unknown discretization type for field %d", field);
554:         for (q = 0; q < Nq; ++q) {
555:           if (fegeom.detJ[q] <= 0.0) SETERRQ3(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Invalid determinant %g for element %D, quadrature points %D", (double)fegeom.detJ[q], cell, q);
556:           if (ierr) {
557:             PetscErrorCode ierr2;
558:             ierr2 = DMPlexVecRestoreClosure(dm, NULL, locX, cell, NULL, &x);CHKERRQ(ierr2);
559:             ierr2 = DMPlexRestoreTransitiveClosure(dm, v, PETSC_FALSE, &starSize, &star);CHKERRQ(ierr2);
560:             ierr2 = PetscFree6(gradsum,interpolant,coords,fegeom.detJ,fegeom.J,fegeom.invJ);CHKERRQ(ierr2);
561:             
562:           }
563:           if (id == PETSCFE_CLASSID)      {PetscFEInterpolateGradient_Static((PetscFE) obj, &x[fieldOffset], &fegeom, q, interpolant);}
564:           else SETERRQ1(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Unknown discretization type for field %d", field);
565:           for (fc = 0; fc < Nc; ++fc) {
566:             const PetscReal wt = quadWeights[q*qNc+qc+fc];

568:             for (d = 0; d < coordDim; ++d) grad[fc*coordDim+d] += interpolant[fc*dim+d]*wt*fegeom.detJ[q];
569:           }
570:         }
571:         fieldOffset += Nb;
572:       }
573:       DMPlexVecRestoreClosure(dm, NULL, locX, cell, NULL, &x);
574:       for (fc = 0; fc < numComponents; ++fc) {
575:         for (d = 0; d < coordDim; ++d) {
576:           gradsum[fc*coordDim+d] += grad[fc*coordDim+d];
577:         }
578:       }
579:       if (debug) {
580:         PetscPrintf(PETSC_COMM_SELF, "Cell %D gradient: [", cell);
581:         for (fc = 0; fc < numComponents; ++fc) {
582:           for (d = 0; d < coordDim; ++d) {
583:             if (fc || d > 0) {PetscPrintf(PETSC_COMM_SELF, ", ");}
584:             PetscPrintf(PETSC_COMM_SELF, "%g", (double)PetscRealPart(grad[fc*coordDim+d]));
585:           }
586:         }
587:         PetscPrintf(PETSC_COMM_SELF, "]\n");
588:       }
589:     }
590:     DMPlexRestoreTransitiveClosure(dm, v, PETSC_FALSE, &starSize, &star);
591:     DMPlexVecSetClosure(dmC, NULL, locC, v, gradsum, INSERT_VALUES);
592:   }
593:   PetscFree6(gradsum,interpolant,coords,fegeom.detJ,fegeom.J,fegeom.invJ);
594:   return(0);
595: }

597: static PetscErrorCode TestFieldGradientProjection(DM dm, DM sw, AppCtx *user)
598: {

600:   MPI_Comm       comm;
601:   KSP            ksp;
602:   Mat            M;                   /* FEM mass matrix */
603:   Mat            M_p;                 /* Particle mass matrix */
604:   Vec            f, rhs, fhat, grad;  /* Particle field f, \int phi_i f, FEM field */
605:   PetscReal      pmoments[3];         /* \int f, \int x f, \int r^2 f */
606:   PetscReal      fmoments[3];         /* \int \hat f, \int x \hat f, \int r^2 \hat f */
607:   PetscInt       m;

611:   PetscObjectGetComm((PetscObject) dm, &comm);
612:   KSPCreate(comm, &ksp);
613:   KSPSetOptionsPrefix(ksp, "ptof_");
614:   DMGetGlobalVector(dm, &fhat);
615:   DMGetGlobalVector(dm, &rhs);
616:   DMGetGlobalVector(dm, &grad);

618:   DMCreateMassMatrix(sw, dm, &M_p);
619:   MatViewFromOptions(M_p, NULL, "-M_p_view");

621:   /* make particle weight vector */
622:   DMSwarmCreateGlobalVectorFromField(sw, "w_q", &f);

624:   /* create matrix RHS vector */
625:   MatMultTranspose(M_p, f, rhs);
626:   DMSwarmDestroyGlobalVectorFromField(sw, "w_q", &f);
627:   PetscObjectSetName((PetscObject) rhs,"rhs");
628:   VecViewFromOptions(rhs, NULL, "-rhs_view");

630:   DMCreateMatrix(dm, &M);
631:   DMPlexSNESComputeJacobianFEM(dm, fhat, M, M, user);

633:   InterpolateGradient(dm, fhat, grad);

635:   MatViewFromOptions(M, NULL, "-M_view");
636:   KSPSetOperators(ksp, M, M);
637:   KSPSetFromOptions(ksp);
638:   KSPSolve(ksp, rhs, grad);
639:   PetscObjectSetName((PetscObject) fhat,"fhat");
640:   VecViewFromOptions(fhat, NULL, "-fhat_view");

642:   /* Check moments of field */
643:   computeParticleMoments(sw, pmoments, user);
644:   computeFEMMoments(dm, grad, fmoments, user);
645:   PetscPrintf(comm, "L2 projection mass: %20.10e, x-momentum: %20.10e, energy: %20.10e.\n", fmoments[0], fmoments[1], fmoments[2]);
646:   for (m = 0; m < 3; ++m) {
647:     if (PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]) > user->momentTol) SETERRQ3(comm, PETSC_ERR_ARG_WRONG, "Moment %D error too large %g > %g", m, PetscAbsReal((fmoments[m] - pmoments[m])/fmoments[m]), user->momentTol);
648:   }

650:   KSPDestroy(&ksp);
651:   MatDestroy(&M);
652:   MatDestroy(&M_p);
653:   DMRestoreGlobalVector(dm, &fhat);
654:   DMRestoreGlobalVector(dm, &rhs);
655:   DMRestoreGlobalVector(dm, &grad);

657:   return(0);
658: }

660: int main (int argc, char * argv[]) {
661:   MPI_Comm       comm;
662:   DM             dm, sw;
663:   AppCtx         user;

666:   PetscInitialize(&argc, &argv, NULL, help);if (ierr) return ierr;
667:   comm = PETSC_COMM_WORLD;
668:   ProcessOptions(comm, &user);
669:   CreateMesh(comm, &dm, &user);
670:   CreateFEM(dm, &user);
671:   CreateParticles(dm, &sw, &user);
672:   TestL2ProjectionParticlesToField(dm, sw, &user);
673:   TestL2ProjectionFieldToParticles(dm, sw, &user);
674:   TestFieldGradientProjection(dm, sw, &user);
675:   DMDestroy(&dm);
676:   DMDestroy(&sw);
677:   PetscFinalize();
678:   return ierr;
679: }


682: /*TEST

684:   # Swarm does not handle complex or quad
685:   build:
686:     requires: !complex double

688:   test:
689:     suffix: proj_tri_0
690:     requires: triangle
691:     args: -dm_plex_box_faces 1,1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
692:     filter: grep -v marker | grep -v atomic | grep -v usage

694:   test:
695:     suffix: proj_tri_2_faces
696:     requires: triangle
697:     args: -dm_plex_box_faces 2,2  -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
698:     filter: grep -v marker | grep -v atomic | grep -v usage

700:   test:
701:     suffix: proj_quad_0
702:     requires: triangle
703:     args: -dm_plex_box_simplex 0 -dm_plex_box_faces 1,1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
704:     filter: grep -v marker | grep -v atomic | grep -v usage

706:   test:
707:     suffix: proj_quad_2_faces
708:     requires: triangle
709:     args: -dm_plex_box_simplex 0 -dm_plex_box_faces 2,2 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
710:     filter: grep -v marker | grep -v atomic | grep -v usage

712:   test:
713:     suffix: proj_tri_5P
714:     requires: triangle
715:     args: -dm_plex_box_faces 1,1 -particlesPerCell 5 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
716:     filter: grep -v marker | grep -v atomic | grep -v usage

718:   test:
719:     suffix: proj_quad_5P
720:     requires: triangle
721:     args: -dm_plex_box_simplex 0 -dm_plex_box_faces 1,1 -particlesPerCell 5 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
722:     filter: grep -v marker | grep -v atomic | grep -v usage

724:   test:
725:     suffix: proj_tri_mdx
726:     requires: triangle
727:     args: -dm_plex_box_faces 1,1 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
728:     filter: grep -v marker | grep -v atomic | grep -v usage

730:   test:
731:     suffix: proj_tri_mdx_5P
732:     requires: triangle
733:     args: -dm_plex_box_faces 1,1 -particlesPerCell 5 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
734:     filter: grep -v marker | grep -v atomic | grep -v usage

736:   test:
737:     suffix: proj_tri_3d
738:     requires: ctetgen
739:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 1,1,1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
740:     filter: grep -v marker | grep -v atomic | grep -v usage

742:   test:
743:     suffix: proj_tri_3d_2_faces
744:     requires: ctetgen
745:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 2,2,2 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
746:     filter: grep -v marker | grep -v atomic | grep -v usage

748:   test:
749:     suffix: proj_tri_3d_5P
750:     requires: ctetgen
751:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 1,1,1 -particlesPerCell 5 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
752:     filter: grep -v marker | grep -v atomic | grep -v usage

754:   test:
755:     suffix: proj_tri_3d_mdx
756:     requires: ctetgen
757:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 1,1,1 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
758:     filter: grep -v marker | grep -v atomic | grep -v usage

760:   test:
761:     suffix: proj_tri_3d_mdx_5P
762:     requires: ctetgen
763:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 1,1,1 -particlesPerCell 5 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
764:     filter: grep -v marker | grep -v atomic | grep -v usage

766:   test:
767:     suffix: proj_tri_3d_mdx_2_faces
768:     requires: ctetgen
769:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 2,2,2 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
770:     filter: grep -v marker | grep -v atomic | grep -v usage

772:   test:
773:     suffix: proj_tri_3d_mdx_5P_2_faces
774:     requires: ctetgen
775:     args: -dm_plex_box_dim 3 -dm_plex_box_faces 2,2,2 -particlesPerCell 5 -mesh_perturbation 1.0e-1 -dm_view -sw_view -petscspace_degree 2 -petscfe_default_quadrature_order {{2 3}} -ptof_pc_type lu  -ftop_ksp_rtol 1e-15 -ftop_ksp_type lsqr -ftop_pc_type none
776:     filter: grep -v marker | grep -v atomic | grep -v usage

778:   test:
779:     suffix: proj_quad_lsqr_scale
780:     requires: !complex
781:     args: -dm_plex_box_simplex 0 -dm_plex_box_faces 4,4 \
782:       -petscspace_degree 2 -petscfe_default_quadrature_order 3 \
783:       -particlesPerCell 200 \
784:       -ptof_pc_type lu  \
785:       -ftop_ksp_rtol 1e-17 -ftop_ksp_type lsqr -ftop_pc_type none

787:   test:
788:     suffix: proj_quad_lsqr_prec_scale
789:     requires: !complex
790:     args: -dm_plex_box_simplex 0 -dm_plex_box_faces 4,4 \
791:       -petscspace_degree 2 -petscfe_default_quadrature_order 3 \
792:       -particlesPerCell 200 \
793:       -ptof_pc_type lu  \
794:       -ftop_ksp_rtol 1e-17 -ftop_ksp_type lsqr -ftop_pc_type lu -ftop_pc_factor_shift_type nonzero -block_diag_prec

796: TEST*/