Actual source code: ex30.c

  1: static char help[] = "Grid based Landau collision operator with PIC interface with OpenMP setup. (one species per grid)\n";

  3: /*
  4:    Support 2.5V with axisymmetric coordinates
  5:      - r,z coordinates
  6:      - Domain and species data input by Landau operator
  7:      - "radius" for each grid, normalized with electron thermal velocity
  8:      - Domain: (0,radius) x (-radius,radius), thus first coordinate x[0] is perpendicular velocity and 2pi*x[0] term is added for axisymmetric
  9:    Supports full 3V

 11:  */

 13: #include "petscdmplex.h"
 14: #include "petscds.h"
 15: #include "petscdmswarm.h"
 16: #include "petscksp.h"
 17: #include <petsc/private/petscimpl.h>
 18: #if defined(PETSC_HAVE_OPENMP) && defined(PETSC_HAVE_THREADSAFETY)
 19:   #include <omp.h>
 20: #endif
 21: #include <petsclandau.h>
 22: #include <petscdmcomposite.h>

 24: typedef struct {
 25:   Mat MpTrans;
 26:   Mat Mp;
 27:   Vec ff;
 28:   Vec uu;
 29: } MatShellCtx;

 31: PetscErrorCode MatMultMtM_SeqAIJ(Mat MtM, Vec xx, Vec yy)
 32: {
 33:   MatShellCtx *matshellctx;

 35:   PetscFunctionBeginUser;
 36:   PetscCall(MatShellGetContext(MtM, &matshellctx));
 37:   PetscCheck(matshellctx, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "No context");
 38:   PetscCall(MatMult(matshellctx->Mp, xx, matshellctx->ff));
 39:   PetscCall(MatMult(matshellctx->MpTrans, matshellctx->ff, yy));
 40:   PetscFunctionReturn(PETSC_SUCCESS);
 41: }

 43: PetscErrorCode MatMultAddMtM_SeqAIJ(Mat MtM, Vec xx, Vec yy, Vec zz)
 44: {
 45:   MatShellCtx *matshellctx;

 47:   PetscFunctionBeginUser;
 48:   PetscCall(MatShellGetContext(MtM, &matshellctx));
 49:   PetscCheck(matshellctx, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "No context");
 50:   PetscCall(MatMult(matshellctx->Mp, xx, matshellctx->ff));
 51:   PetscCall(MatMultAdd(matshellctx->MpTrans, matshellctx->ff, yy, zz));
 52:   PetscFunctionReturn(PETSC_SUCCESS);
 53: }

 55: PetscErrorCode createSwarm(const DM dm, PetscInt dim, DM *sw)
 56: {
 57:   PetscInt Nc = 1;

 59:   PetscFunctionBeginUser;
 60:   PetscCall(DMCreate(PETSC_COMM_SELF, sw));
 61:   PetscCall(DMSetType(*sw, DMSWARM));
 62:   PetscCall(DMSetDimension(*sw, dim));
 63:   PetscCall(DMSwarmSetType(*sw, DMSWARM_PIC));
 64:   PetscCall(DMSwarmSetCellDM(*sw, dm));
 65:   PetscCall(DMSwarmRegisterPetscDatatypeField(*sw, "w_q", Nc, PETSC_SCALAR));
 66:   PetscCall(DMSwarmFinalizeFieldRegister(*sw));
 67:   PetscCall(DMSetFromOptions(*sw));
 68:   PetscFunctionReturn(PETSC_SUCCESS);
 69: }

 71: PetscErrorCode gridToParticles(const DM dm, DM sw, Vec rhs, Vec work, Mat M_p, Mat Mass)
 72: {
 73:   PetscBool    is_lsqr;
 74:   KSP          ksp;
 75:   Mat          PM_p = NULL, MtM, D;
 76:   Vec          ff;
 77:   PetscInt     N, M, nzl;
 78:   MatShellCtx *matshellctx;

 80:   PetscFunctionBeginUser;
 81:   PetscCall(MatMult(Mass, rhs, work));
 82:   PetscCall(VecCopy(work, rhs));
 83:   // pseudo-inverse
 84:   PetscCall(KSPCreate(PETSC_COMM_SELF, &ksp));
 85:   PetscCall(KSPSetOptionsPrefix(ksp, "ftop_"));
 86:   PetscCall(KSPSetFromOptions(ksp));
 87:   PetscCall(PetscObjectTypeCompare((PetscObject)ksp, KSPLSQR, &is_lsqr));
 88:   if (!is_lsqr) {
 89:     PetscCall(MatGetLocalSize(M_p, &M, &N));
 90:     if (N > M) {
 91:       PC pc;
 92:       PetscCall(PetscInfo(ksp, " M (%" PetscInt_FMT ") < M (%" PetscInt_FMT ") -- skip revert to lsqr\n", M, N));
 93:       is_lsqr = PETSC_TRUE;
 94:       PetscCall(KSPSetType(ksp, KSPLSQR));
 95:       PetscCall(KSPGetPC(ksp, &pc));
 96:       PetscCall(PCSetType(pc, PCNONE)); // could put in better solver -ftop_pc_type bjacobi -ftop_sub_pc_type lu -ftop_sub_pc_factor_shift_type nonzero
 97:     } else {
 98:       PetscCall(PetscNew(&matshellctx));
 99:       PetscCall(MatCreateShell(PetscObjectComm((PetscObject)dm), N, N, PETSC_DECIDE, PETSC_DECIDE, matshellctx, &MtM));
100:       PetscCall(MatTranspose(M_p, MAT_INITIAL_MATRIX, &matshellctx->MpTrans));
101:       matshellctx->Mp = M_p;
102:       PetscCall(MatShellSetOperation(MtM, MATOP_MULT, (void (*)(void))MatMultMtM_SeqAIJ));
103:       PetscCall(MatShellSetOperation(MtM, MATOP_MULT_ADD, (void (*)(void))MatMultAddMtM_SeqAIJ));
104:       PetscCall(MatCreateVecs(M_p, &matshellctx->uu, &matshellctx->ff));
105:       PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, N, N, 1, NULL, &D));
106:       PetscCall(MatViewFromOptions(matshellctx->MpTrans, NULL, "-ftop2_Mp_mat_view"));
107:       for (int i = 0; i < N; i++) {
108:         const PetscScalar *vals;
109:         const PetscInt    *cols;
110:         PetscScalar        dot = 0;
111:         PetscCall(MatGetRow(matshellctx->MpTrans, i, &nzl, &cols, &vals));
112:         for (int ii = 0; ii < nzl; ii++) dot += PetscSqr(vals[ii]);
113:         PetscCheck(dot != 0.0, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Row %d is empty", i);
114:         PetscCall(MatSetValue(D, i, i, dot, INSERT_VALUES));
115:       }
116:       PetscCall(MatAssemblyBegin(D, MAT_FINAL_ASSEMBLY));
117:       PetscCall(MatAssemblyEnd(D, MAT_FINAL_ASSEMBLY));
118:       PetscCall(PetscInfo(M_p, "createMtMKSP Have %" PetscInt_FMT " eqs, nzl = %" PetscInt_FMT "\n", N, nzl));
119:       PetscCall(KSPSetOperators(ksp, MtM, D));
120:       PetscCall(MatViewFromOptions(D, NULL, "-ftop2_D_mat_view"));
121:       PetscCall(MatViewFromOptions(M_p, NULL, "-ftop2_Mp_mat_view"));
122:       PetscCall(MatViewFromOptions(matshellctx->MpTrans, NULL, "-ftop2_MpTranspose_mat_view"));
123:       PetscCall(MatViewFromOptions(MtM, NULL, "-ftop2_MtM_mat_view"));
124:     }
125:   }
126:   if (is_lsqr) {
127:     PC        pc;
128:     PetscBool is_bjac;
129:     PetscCall(KSPGetPC(ksp, &pc));
130:     PetscCall(PetscObjectTypeCompare((PetscObject)pc, PCBJACOBI, &is_bjac));
131:     if (is_bjac) {
132:       PetscCall(DMSwarmCreateMassMatrixSquare(sw, dm, &PM_p));
133:       PetscCall(KSPSetOperators(ksp, M_p, PM_p));
134:     } else {
135:       PetscCall(KSPSetOperators(ksp, M_p, M_p));
136:     }
137:   }
138:   PetscCall(DMSwarmCreateGlobalVectorFromField(sw, "w_q", &ff)); // this grabs access
139:   if (!is_lsqr) {
140:     PetscCall(KSPSolve(ksp, rhs, matshellctx->uu));
141:     PetscCall(MatMult(M_p, matshellctx->uu, ff));
142:     PetscCall(MatDestroy(&matshellctx->MpTrans));
143:     PetscCall(VecDestroy(&matshellctx->ff));
144:     PetscCall(VecDestroy(&matshellctx->uu));
145:     PetscCall(MatDestroy(&D));
146:     PetscCall(MatDestroy(&MtM));
147:     PetscCall(PetscFree(matshellctx));
148:   } else {
149:     PetscCall(KSPSolveTranspose(ksp, rhs, ff));
150:   }
151:   PetscCall(KSPDestroy(&ksp));
152:   /* Visualize particle field */
153:   PetscCall(VecViewFromOptions(ff, NULL, "-weights_view"));
154:   PetscCall(MatDestroy(&PM_p));
155:   PetscCall(DMSwarmDestroyGlobalVectorFromField(sw, "w_q", &ff));

157:   PetscFunctionReturn(PETSC_SUCCESS);
158: }

160: PetscErrorCode particlesToGrid(const DM dm, DM sw, const PetscInt Np, const PetscInt a_tid, const PetscInt dim, const PetscReal xx[], const PetscReal yy[], const PetscReal zz[], const PetscReal a_wp[], Vec rho, Mat *Mp_out)
161: {
162:   PetscBool     removePoints = PETSC_TRUE;
163:   PetscReal    *wq, *coords;
164:   PetscDataType dtype;
165:   Mat           M_p;
166:   Vec           ff;
167:   PetscInt      bs, p, zero = 0;

169:   PetscFunctionBeginUser;
170:   PetscCall(DMSwarmSetLocalSizes(sw, Np, zero));
171:   PetscCall(DMSwarmGetField(sw, "w_q", &bs, &dtype, (void **)&wq));
172:   PetscCall(DMSwarmGetField(sw, "DMSwarmPIC_coor", &bs, &dtype, (void **)&coords));
173:   for (p = 0; p < Np; p++) {
174:     coords[p * dim + 0] = xx[p];
175:     coords[p * dim + 1] = yy[p];
176:     wq[p]               = a_wp[p];
177:     if (dim == 3) coords[p * dim + 2] = zz[p];
178:   }
179:   PetscCall(DMSwarmRestoreField(sw, "DMSwarmPIC_coor", &bs, &dtype, (void **)&coords));
180:   PetscCall(DMSwarmRestoreField(sw, "w_q", &bs, &dtype, (void **)&wq));
181:   PetscCall(DMSwarmMigrate(sw, removePoints));
182:   PetscCall(PetscObjectSetName((PetscObject)sw, "Particle Grid"));

184:   /* This gives M f = \int_\Omega \phi f, which looks like a rhs for a PDE */
185:   PetscCall(DMCreateMassMatrix(sw, dm, &M_p));

187:   PetscCall(PetscObjectSetName((PetscObject)rho, "rho"));
188:   PetscCall(DMSwarmCreateGlobalVectorFromField(sw, "w_q", &ff));
189:   PetscCall(PetscObjectSetName((PetscObject)ff, "weights"));
190:   PetscCall(MatMultTranspose(M_p, ff, rho));
191:   PetscCall(DMSwarmDestroyGlobalVectorFromField(sw, "w_q", &ff));

193:   // output
194:   *Mp_out = M_p;

196:   PetscFunctionReturn(PETSC_SUCCESS);
197: }
198: static void maxwellian(PetscInt dim, const PetscReal x[], PetscReal kt_m, PetscReal n, PetscScalar *u)
199: {
200:   PetscInt  i;
201:   PetscReal v2 = 0, theta = 2.0 * kt_m; /* theta = 2kT/mc^2 */

203:   /* compute the exponents, v^2 */
204:   for (i = 0; i < dim; ++i) v2 += x[i] * x[i];
205:   /* evaluate the Maxwellian */
206:   u[0] = n * PetscPowReal(PETSC_PI * theta, -1.5) * (PetscExpReal(-v2 / theta));
207: }

209: #define MAX_NUM_THRDS 12
210: PetscErrorCode go(TS ts, Vec X, const PetscInt NUserV, const PetscInt a_Np, const PetscInt dim, const PetscInt b_target, const PetscInt g_target)
211: {
212:   DM             pack, *globSwarmArray, grid_dm[LANDAU_MAX_GRIDS];
213:   Mat           *globMpArray, g_Mass[LANDAU_MAX_GRIDS];
214:   KSP            t_ksp[LANDAU_MAX_GRIDS][MAX_NUM_THRDS];
215:   Vec            t_fhat[LANDAU_MAX_GRIDS][MAX_NUM_THRDS];
216:   PetscInt       nDMs, glb_b_id, nTargetP = 0;
217:   PetscErrorCode ierr = 0; // used for inside thread loops
218: #if defined(PETSC_HAVE_OPENMP) && defined(PETSC_HAVE_THREADSAFETY)
219:   PetscInt numthreads = PetscNumOMPThreads;
220: #else
221:   PetscInt numthreads = 1;
222: #endif
223:   LandauCtx *ctx;
224:   Vec       *globXArray;
225:   PetscReal  moments_0[3], moments_1[3], dt_init;

227:   PetscFunctionBeginUser;
228:   PetscCheck(numthreads <= MAX_NUM_THRDS, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Too many threads %" PetscInt_FMT " > %d", numthreads, MAX_NUM_THRDS);
229:   PetscCheck(numthreads > 0, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Number threads %" PetscInt_FMT " > %d", numthreads, MAX_NUM_THRDS);
230:   PetscCall(TSGetDM(ts, &pack));
231:   PetscCall(DMGetApplicationContext(pack, &ctx));
232:   PetscCheck(ctx->batch_sz % numthreads == 0, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "batch size (-dm_landau_batch_size) %" PetscInt_FMT "  mod #threads %" PetscInt_FMT " must equal zero", ctx->batch_sz, numthreads);
233:   PetscCall(DMCompositeGetNumberDM(pack, &nDMs));
234:   PetscCall(PetscInfo(pack, "Have %" PetscInt_FMT " total grids, with %" PetscInt_FMT " Landau local batched and %" PetscInt_FMT " global items (vertices)\n", ctx->num_grids, ctx->batch_sz, NUserV));
235:   PetscCall(PetscMalloc(sizeof(*globXArray) * nDMs, &globXArray));
236:   PetscCall(PetscMalloc(sizeof(*globMpArray) * nDMs, &globMpArray));
237:   PetscCall(PetscMalloc(sizeof(*globSwarmArray) * nDMs, &globSwarmArray));
238:   PetscCall(DMViewFromOptions(ctx->plex[g_target], NULL, "-ex30_dm_view"));
239:   // create mass matrices
240:   PetscCall(VecZeroEntries(X));
241:   PetscCall(DMCompositeGetAccessArray(pack, X, nDMs, NULL, globXArray)); // just to duplicate
242:   for (PetscInt grid = 0; grid < ctx->num_grids; grid++) {               // add same particels for all grids
243:     Vec          subX = globXArray[LAND_PACK_IDX(0, grid)];
244:     DM           dm   = ctx->plex[grid];
245:     PetscSection s;
246:     grid_dm[grid] = dm;
247:     PetscCall(DMCreateMassMatrix(dm, dm, &g_Mass[grid]));
248:     //
249:     PetscCall(DMGetLocalSection(dm, &s));
250:     PetscCall(DMPlexCreateClosureIndex(dm, s));
251:     for (int tid = 0; tid < numthreads; tid++) {
252:       PetscCall(VecDuplicate(subX, &t_fhat[grid][tid]));
253:       PetscCall(KSPCreate(PETSC_COMM_SELF, &t_ksp[grid][tid]));
254:       PetscCall(KSPSetOptionsPrefix(t_ksp[grid][tid], "ptof_"));
255:       PetscCall(KSPSetOperators(t_ksp[grid][tid], g_Mass[grid], g_Mass[grid]));
256:       PetscCall(KSPSetFromOptions(t_ksp[grid][tid]));
257:     }
258:   }
259:   PetscCall(DMCompositeRestoreAccessArray(pack, X, nDMs, NULL, globXArray));
260:   // create particle raw data. could use OMP with a thread safe malloc, but this is just the fake user
261:   for (int i = 0; i < 3; i++) moments_0[i] = moments_1[i] = 0;
262:   PetscCall(TSGetTimeStep(ts, &dt_init)); // we could have an adaptive time stepper
263:   for (PetscInt global_batch_id = 0; global_batch_id < NUserV; global_batch_id += ctx->batch_sz) {
264:     PetscCall(TSSetTime(ts, 0));
265:     PetscCall(TSSetStepNumber(ts, 0));
266:     PetscCall(TSSetTimeStep(ts, dt_init));
267:     PetscCall(DMCompositeGetAccessArray(pack, X, nDMs, NULL, globXArray));
268:     if (b_target >= global_batch_id && b_target < global_batch_id + ctx->batch_sz) PetscCall(PetscObjectSetName((PetscObject)globXArray[LAND_PACK_IDX(b_target % ctx->batch_sz, g_target)], "rho"));
269:     // create fake particles
270:     for (PetscInt b_id_0 = 0; b_id_0 < ctx->batch_sz; b_id_0 += numthreads) {
271:       PetscReal *xx_t[LANDAU_MAX_GRIDS][MAX_NUM_THRDS], *yy_t[LANDAU_MAX_GRIDS][MAX_NUM_THRDS], *zz_t[LANDAU_MAX_GRIDS][MAX_NUM_THRDS], *wp_t[LANDAU_MAX_GRIDS][MAX_NUM_THRDS];
272:       PetscInt   Np_t[LANDAU_MAX_GRIDS][MAX_NUM_THRDS];
273:       // make particles
274:       for (int tid = 0; tid < numthreads; tid++) {
275:         const PetscInt b_id = b_id_0 + tid;
276:         if ((glb_b_id = global_batch_id + b_id) < NUserV) {        // the ragged edge of the last batch
277:           PetscInt Npp0 = a_Np + (glb_b_id % a_Np), NN;            // fake user: number of particels in each dimension with add some load imbalance and diff (<2x)
278:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
279:             const PetscReal kT_m = ctx->k * ctx->thermal_temps[ctx->species_offset[grid]] / ctx->masses[ctx->species_offset[grid]] / (ctx->v_0 * ctx->v_0); /* theta = 2kT/mc^2 per species -- TODO */
280:             ;
281:             PetscReal lo[3] = {-ctx->radius[grid], -ctx->radius[grid], -ctx->radius[grid]}, hi[3] = {ctx->radius[grid], ctx->radius[grid], ctx->radius[grid]}, hp[3], vole; // would be nice to get box from DM
282:             PetscInt  Npi = Npp0, Npj = 2 * Npp0, Npk = 1;
283:             if (dim == 2) lo[0] = 0; // Landau coordinate (r,z)
284:             else Npi = Npj = Npk = Npp0;
285:             // User: use glb_b_id to index into your data
286:             NN = Npi * Npj * Npk; // make a regular grid of particles Npp x Npp
287:             if (glb_b_id == b_target) {
288:               nTargetP = NN;
289:               PetscCall(PetscInfo(pack, "Target %" PetscInt_FMT " with %" PetscInt_FMT " particels\n", glb_b_id, NN));
290:             }
291:             Np_t[grid][tid] = NN;
292:             PetscCall(PetscMalloc4(NN, &xx_t[grid][tid], NN, &yy_t[grid][tid], NN, &wp_t[grid][tid], dim == 2 ? 1 : NN, &zz_t[grid][tid]));
293:             hp[0] = (hi[0] - lo[0]) / Npi;
294:             hp[1] = (hi[1] - lo[1]) / Npj;
295:             hp[2] = (hi[2] - lo[2]) / Npk;
296:             if (dim == 2) hp[2] = 1;
297:             PetscCall(PetscInfo(pack, " lo = %14.7e, hi = %14.7e; hp = %14.7e, %14.7e; kT_m = %g; \n", (double)lo[1], (double)hi[1], (double)hp[0], (double)hp[1], (double)kT_m)); // temp
298:             vole = hp[0] * hp[1] * hp[2] * ctx->n[grid];                                                                                                                           // fix for multi-species
299:             PetscCall(PetscInfo(pack, "Vertex %" PetscInt_FMT ", grid %" PetscInt_FMT " with %" PetscInt_FMT " particles (diagnostic target = %" PetscInt_FMT ")\n", glb_b_id, grid, NN, b_target));
300:             for (int pj = 0, pp = 0; pj < Npj; pj++) {
301:               for (int pk = 0; pk < Npk; pk++) {
302:                 for (int pi = 0; pi < Npi; pi++, pp++) {
303:                   xx_t[grid][tid][pp] = lo[0] + hp[0] / 2.0 + pi * hp[0];
304:                   yy_t[grid][tid][pp] = lo[1] + hp[1] / 2.0 + pj * hp[1];
305:                   if (dim == 3) zz_t[grid][tid][pp] = lo[2] + hp[2] / 2.0 + pk * hp[2];
306:                   {
307:                     PetscReal x[] = {xx_t[grid][tid][pp], yy_t[grid][tid][pp], dim == 2 ? 0 : zz_t[grid][tid][pp]};
308:                     maxwellian(dim, x, kT_m, vole, &wp_t[grid][tid][pp]);
309:                     //PetscCall(PetscInfo(pack,"%" PetscInt_FMT ") x = %14.7e, %14.7e, %14.7e, n = %14.7e, w = %14.7e\n", pp, x[0], x[1], dim==2 ? 0 : x[2], ctx->n[grid], wp_t[grid][tid][pp])); // temp
310:                     if (glb_b_id == b_target) {
311:                       PetscReal v2 = 0, fact = dim == 2 ? 2.0 * PETSC_PI * x[0] : 1;
312:                       for (int i = 0; i < dim; ++i) v2 += PetscSqr(x[i]);
313:                       moments_0[0] += fact * wp_t[grid][tid][pp] * ctx->n_0 * ctx->masses[ctx->species_offset[grid]];
314:                       moments_0[1] += fact * wp_t[grid][tid][pp] * ctx->n_0 * ctx->v_0 * ctx->masses[ctx->species_offset[grid]] * x[1]; // z-momentum
315:                       moments_0[2] += fact * wp_t[grid][tid][pp] * ctx->n_0 * ctx->v_0 * ctx->v_0 * ctx->masses[ctx->species_offset[grid]] * v2;
316:                     }
317:                   }
318:                 }
319:               }
320:             }
321:           } // grid
322:         }   // active
323:       }     // fake threads
324:       /* Create particle swarm */
325:       PetscPragmaOMP(parallel for)
326:       for (int tid = 0; tid < numthreads; tid++) {
327:         const PetscInt b_id = b_id_0 + tid;
328:         if ((glb_b_id = global_batch_id + b_id) < NUserV) { // the ragged edge of the last batch
329:           //PetscCall(PetscInfo(pack,"Create swarms for 'glob' index %" PetscInt_FMT " create swarm\n",glb_b_id));
330:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
331:             PetscErrorCode ierr_t;
332:             PetscSection   section;
333:             PetscInt       Nf;
334:             DM             dm = grid_dm[grid];
335:             ierr_t            = DMGetLocalSection(dm, &section);
336:             ierr_t            = PetscSectionGetNumFields(section, &Nf);
337:             if (Nf != 1) ierr_t = 9999;
338:             else {
339:               ierr_t = DMViewFromOptions(dm, NULL, "-dm_view");
340:               ierr_t = PetscInfo(pack, "call createSwarm [%" PetscInt_FMT ".%" PetscInt_FMT "] local batch index %" PetscInt_FMT "\n", b_id, grid, LAND_PACK_IDX(b_id, grid));
341:               ierr_t = createSwarm(dm, dim, &globSwarmArray[LAND_PACK_IDX(b_id, grid)]);
342:             }
343:             if (ierr_t) ierr = ierr_t;
344:           }
345:         } // active
346:       }
347:       PetscCheck(ierr != 9999, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Only support one species per grid");
348:       PetscCheck(!ierr, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Error in OMP loop. ierr = %d", (int)ierr);
349:       // p --> g: make globMpArray & set X
350:       PetscPragmaOMP(parallel for)
351:       for (int tid = 0; tid < numthreads; tid++) {
352:         const PetscInt b_id = b_id_0 + tid;
353:         if ((glb_b_id = global_batch_id + b_id) < NUserV) {
354:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
355:             PetscErrorCode ierr_t;
356:             DM             dm   = grid_dm[grid];
357:             DM             sw   = globSwarmArray[LAND_PACK_IDX(b_id, grid)];
358:             Vec            subX = globXArray[LAND_PACK_IDX(b_id, grid)], work = t_fhat[grid][tid];
359:             ierr_t = PetscInfo(pack, "particlesToGrid %" PetscInt_FMT ".%" PetscInt_FMT ") particlesToGrid for local batch %" PetscInt_FMT "\n", global_batch_id, grid, LAND_PACK_IDX(b_id, grid));
360:             ierr_t = particlesToGrid(dm, sw, Np_t[grid][tid], tid, dim, xx_t[grid][tid], yy_t[grid][tid], zz_t[grid][tid], wp_t[grid][tid], subX, &globMpArray[LAND_PACK_IDX(b_id, grid)]);
361:             if (ierr_t) ierr = ierr_t;
362:             // u = M^_1 f_w
363:             ierr_t = VecCopy(subX, work);
364:             ierr_t = KSPSolve(t_ksp[grid][tid], work, subX);
365:             if (ierr_t) ierr = ierr_t;
366:           }
367:         }
368:       }
369:       PetscCheck(!ierr, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Error in OMP loop. ierr = %d", (int)ierr);
370:       /* Cleanup */
371:       for (int tid = 0; tid < numthreads; tid++) {
372:         const PetscInt b_id = b_id_0 + tid;
373:         if ((glb_b_id = global_batch_id + b_id) < NUserV) {
374:           PetscCall(PetscInfo(pack, "Free for global batch %" PetscInt_FMT " of %" PetscInt_FMT "\n", glb_b_id + 1, NUserV));
375:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
376:             PetscCall(PetscFree4(xx_t[grid][tid], yy_t[grid][tid], wp_t[grid][tid], zz_t[grid][tid]));
377:           }
378:         } // active
379:       }
380:     } // batches
381:     if (b_target >= global_batch_id && b_target < global_batch_id + ctx->batch_sz) PetscCall(VecViewFromOptions(globXArray[LAND_PACK_IDX(b_target % ctx->batch_sz, g_target)], NULL, "-ex30_vec_view"));
382:     PetscCall(DMCompositeRestoreAccessArray(pack, X, nDMs, NULL, globXArray));
383:     PetscCall(DMPlexLandauPrintNorms(X, 0));
384:     // advance
385:     PetscCall(TSSetSolution(ts, X));
386:     PetscCall(PetscInfo(pack, "Advance vertex %" PetscInt_FMT " to %" PetscInt_FMT " (with padding)\n", global_batch_id, global_batch_id + ctx->batch_sz));
387:     PetscCall(TSSolve(ts, X));
388:     PetscCall(DMPlexLandauPrintNorms(X, 1));
389:     PetscCall(DMCompositeGetAccessArray(pack, X, nDMs, NULL, globXArray));
390:     // map back to particles
391:     for (PetscInt b_id_0 = 0; b_id_0 < ctx->batch_sz; b_id_0 += numthreads) {
392:       PetscCall(PetscInfo(pack, "g2p: global batch %" PetscInt_FMT " of %" PetscInt_FMT ", Landau batch %" PetscInt_FMT " of %" PetscInt_FMT ": map back to particles\n", global_batch_id + 1, NUserV, b_id_0 + 1, ctx->batch_sz));
393:       PetscPragmaOMP(parallel for)
394:       for (int tid = 0; tid < numthreads; tid++) {
395:         const PetscInt b_id = b_id_0 + tid;
396:         if ((glb_b_id = global_batch_id + b_id) < NUserV) {
397:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
398:             PetscErrorCode ierr_t;
399:             ierr_t = PetscInfo(pack, "gridToParticles: global batch %" PetscInt_FMT ", local batch b=%" PetscInt_FMT ", grid g=%" PetscInt_FMT ", index(b,g) %" PetscInt_FMT "\n", global_batch_id, b_id, grid, LAND_PACK_IDX(b_id, grid));
400:             ierr_t = gridToParticles(grid_dm[grid], globSwarmArray[LAND_PACK_IDX(b_id, grid)], globXArray[LAND_PACK_IDX(b_id, grid)], t_fhat[grid][tid], globMpArray[LAND_PACK_IDX(b_id, grid)], g_Mass[grid]);
401:             if (ierr_t) ierr = ierr_t;
402:           }
403:         }
404:       }
405:       PetscCheck(!ierr, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Error in OMP loop. ierr = %d", (int)ierr);
406:       /* Cleanup, and get data */
407:       PetscCall(PetscInfo(pack, "Cleanup batches %" PetscInt_FMT " to %" PetscInt_FMT "\n", b_id_0, b_id_0 + numthreads));
408:       for (int tid = 0; tid < numthreads; tid++) {
409:         const PetscInt b_id = b_id_0 + tid;
410:         if ((glb_b_id = global_batch_id + b_id) < NUserV) {
411:           for (PetscInt grid = 0; grid < ctx->num_grids; grid++) {
412:             PetscDataType dtype;
413:             PetscReal    *wp, *coords;
414:             DM            sw = globSwarmArray[LAND_PACK_IDX(b_id, grid)];
415:             PetscInt      npoints, bs = 1;
416:             PetscCall(DMSwarmGetField(sw, "w_q", &bs, &dtype, (void **)&wp)); // take data out here
417:             if (glb_b_id == b_target) {
418:               PetscCall(DMSwarmGetField(sw, "DMSwarmPIC_coor", &bs, &dtype, (void **)&coords));
419:               PetscCall(DMSwarmGetLocalSize(sw, &npoints));
420:               for (int p = 0; p < npoints; p++) {
421:                 PetscReal v2 = 0, fact = dim == 2 ? 2.0 * PETSC_PI * coords[p * dim + 0] : 1;
422:                 for (int i = 0; i < dim; ++i) v2 += PetscSqr(coords[p * dim + i]);
423:                 moments_1[0] += fact * wp[p] * ctx->n_0 * ctx->masses[ctx->species_offset[grid]];
424:                 moments_1[1] += fact * wp[p] * ctx->n_0 * ctx->v_0 * ctx->masses[ctx->species_offset[grid]] * coords[p * dim + 1]; // z-momentum
425:                 moments_1[2] += fact * wp[p] * ctx->n_0 * ctx->v_0 * ctx->v_0 * ctx->masses[ctx->species_offset[grid]] * v2;
426:               }
427:               PetscCall(DMSwarmRestoreField(sw, "DMSwarmPIC_coor", &bs, &dtype, (void **)&coords));
428:             }
429:             PetscCall(DMSwarmRestoreField(sw, "w_q", &bs, &dtype, (void **)&wp));
430:             PetscCall(DMDestroy(&globSwarmArray[LAND_PACK_IDX(b_id, grid)]));
431:             PetscCall(MatDestroy(&globMpArray[LAND_PACK_IDX(b_id, grid)]));
432:           }
433:         }
434:       }
435:     } // thread batch
436:     PetscCall(DMCompositeRestoreAccessArray(pack, X, nDMs, NULL, globXArray));
437:   } // user batch
438:   /* Cleanup */
439:   PetscCall(PetscFree(globXArray));
440:   PetscCall(PetscFree(globSwarmArray));
441:   PetscCall(PetscFree(globMpArray));
442:   // clean up mass matrices
443:   for (PetscInt grid = 0; grid < ctx->num_grids; grid++) { // add same particels for all grids
444:     PetscCall(MatDestroy(&g_Mass[grid]));
445:     for (int tid = 0; tid < numthreads; tid++) {
446:       PetscCall(VecDestroy(&t_fhat[grid][tid]));
447:       PetscCall(KSPDestroy(&t_ksp[grid][tid]));
448:     }
449:   }
450:   {
451:     PetscReal relerr = PetscAbsReal((moments_1[2] - moments_0[2]) / moments_0[2]), logEerr = PetscLog10Real(relerr);
452:     PetscCall(PetscInfo(X, "Total number density: %20.12e (%20.12e); x-momentum = %20.12e (%20.12e); energy = %20.12e (%20.12e) rerr = %e (log10(rerr) = %e, %" PetscInt_FMT "), %" PetscInt_FMT " particles. Use %" PetscInt_FMT " threads\n", (double)moments_1[0], (double)moments_0[0], (double)moments_1[1], (double)moments_0[1], (double)moments_1[2], (double)moments_0[2], (double)relerr, (double)logEerr, -((-(PetscInt)logEerr + 1) / 2) * 2, nTargetP, numthreads));
453:     PetscFunctionReturn(PETSC_SUCCESS);
454:   }
455:   PetscFunctionReturn(PETSC_SUCCESS);
456: }

458: int main(int argc, char **argv)
459: {
460:   DM         pack;
461:   Vec        X;
462:   PetscInt   dim = 2, nvert = 1, Np = 10, btarget = 0, gtarget = 0;
463:   TS         ts;
464:   Mat        J;
465:   LandauCtx *ctx;

467:   PetscFunctionBeginUser;
468:   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
469:   // process args
470:   PetscOptionsBegin(PETSC_COMM_SELF, "", "Collision Options", "DMPLEX");
471:   PetscCall(PetscOptionsInt("-number_spatial_vertices", "Number of user spatial vertices to be batched for Landau", "ex30.c", nvert, &nvert, NULL));
472:   PetscCall(PetscOptionsInt("-dim", "Velocity space dimension", "ex30.c", dim, &dim, NULL));
473:   PetscCall(PetscOptionsInt("-number_particles_per_dimension", "Number of particles per grid, with slight modification per spatial vertex, in each dimension of base Cartesian grid", "ex30.c", Np, &Np, NULL));
474:   PetscCall(PetscOptionsInt("-view_vertex_target", "Batch to view with diagnostics", "ex30.c", btarget, &btarget, NULL));
475:   PetscCheck(btarget < nvert, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Batch to view %" PetscInt_FMT " should be < number of vertices %" PetscInt_FMT, btarget, nvert);
476:   PetscCall(PetscOptionsInt("-view_grid_target", "Grid to view with diagnostics", "ex30.c", gtarget, &gtarget, NULL));
477:   PetscOptionsEnd();
478:   /* Create a mesh */
479:   PetscCall(DMPlexLandauCreateVelocitySpace(PETSC_COMM_SELF, dim, "", &X, &J, &pack));
480:   PetscCall(DMSetUp(pack));
481:   PetscCall(DMSetOutputSequenceNumber(pack, 0, 0.0));
482:   PetscCall(DMGetApplicationContext(pack, &ctx));
483:   PetscCheck(gtarget < ctx->num_grids, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Grid to view %" PetscInt_FMT " should be < number of grids %" PetscInt_FMT, gtarget, ctx->num_grids);
484:   PetscCheck(nvert >= ctx->batch_sz, PETSC_COMM_WORLD, PETSC_ERR_ARG_OUTOFRANGE, "Number of vertices %" PetscInt_FMT " should be <= batch size %" PetscInt_FMT, nvert, ctx->batch_sz);
485:   /* Create timestepping solver context */
486:   PetscCall(TSCreate(PETSC_COMM_SELF, &ts));
487:   PetscCall(TSSetDM(ts, pack));
488:   PetscCall(TSSetIFunction(ts, NULL, DMPlexLandauIFunction, NULL));
489:   PetscCall(TSSetIJacobian(ts, J, J, DMPlexLandauIJacobian, NULL));
490:   PetscCall(TSSetExactFinalTime(ts, TS_EXACTFINALTIME_STEPOVER));
491:   PetscCall(TSSetFromOptions(ts));
492:   PetscCall(PetscObjectSetName((PetscObject)X, "X"));
493:   // do particle advance
494:   PetscCall(go(ts, X, nvert, Np, dim, btarget, gtarget));
495:   PetscCall(MatZeroEntries(J)); // need to zero out so as to not reuse it in Landau's logic
496:   /* clean up */
497:   PetscCall(DMPlexLandauDestroyVelocitySpace(&pack));
498:   PetscCall(TSDestroy(&ts));
499:   PetscCall(VecDestroy(&X));
500:   PetscCall(PetscFinalize());
501:   return 0;
502: }

504: /*TEST

506:   build:
507:     requires: !complex p4est

509:   testset:
510:     requires: double defined(PETSC_USE_DMLANDAU_2D)
511:     output_file: output/ex30_0.out
512:     args: -dim 2 -petscspace_degree 3 -dm_landau_type p4est -dm_landau_num_species_grid 1,1,1 -dm_landau_amr_levels_max 0,0,0 \
513:           -dm_landau_amr_post_refine 1 -number_particles_per_dimension 10 -dm_plex_hash_location \
514:           -dm_landau_batch_size 2 -number_spatial_vertices 3 -dm_landau_batch_view_idx 1 -view_vertex_target 2 -view_grid_target 1 \
515:           -dm_landau_n 1.000018,1,1e-6 -dm_landau_thermal_temps 2,1,1 -dm_landau_ion_masses 2,180 -dm_landau_ion_charges 1,18 \
516:           -ftop_ksp_converged_reason -ftop_ksp_rtol 1e-10 -ftop_ksp_type lsqr -ftop_pc_type bjacobi -ftop_sub_pc_factor_shift_type nonzero -ftop_sub_pc_type lu \
517:           -ksp_type preonly -pc_type lu -dm_landau_verbose 4 \
518:           -ptof_ksp_type cg -ptof_pc_type jacobi -ptof_ksp_converged_reason -ptof_ksp_rtol 1e-12\
519:           -snes_converged_reason -snes_monitor -snes_rtol 1e-14 -snes_stol 1e-14\
520:           -ts_dt 0.01 -ts_rtol 1e-1 -ts_exact_final_time stepover -ts_max_snes_failures -1 -ts_max_steps 1 -ts_monitor -ts_type beuler -info :vec

522:     test:
523:       suffix: cpu
524:       args: -dm_landau_device_type cpu
525:     test:
526:       suffix: kokkos
527:       requires: kokkos_kernels
528:       args: -dm_landau_device_type kokkos -dm_mat_type aijkokkos -dm_vec_type kokkos
529:     test:
530:       suffix: cuda
531:       requires: cuda
532:       args: -dm_landau_device_type cuda -dm_mat_type aijcusparse -dm_vec_type cuda

534:   testset:
535:     requires: double !defined(PETSC_USE_DMLANDAU_2D)
536:     output_file: output/ex30_3d.out
537:     args: -dim 3 -petscspace_degree 2 -dm_landau_type p8est -dm_landau_num_species_grid 1,1,1 -dm_landau_amr_levels_max 0,0,0 \
538:           -dm_landau_amr_post_refine 0 -number_particles_per_dimension 5 -dm_plex_hash_location \
539:           -dm_landau_batch_size 1 -number_spatial_vertices 1 -dm_landau_batch_view_idx 0 -view_vertex_target 0 -view_grid_target 0 \
540:           -dm_landau_n 1.000018,1,1e-6 -dm_landau_thermal_temps 2,1,1 -dm_landau_ion_masses 2,180 -dm_landau_ion_charges 1,18 \
541:           -ftop_ksp_converged_reason -ftop_ksp_rtol 1e-12 -ftop_ksp_type cg -ftop_pc_type jacobi \
542:           -ksp_type preonly -pc_type lu \
543:           -ptof_ksp_type cg -ptof_pc_type jacobi -ptof_ksp_converged_reason -ptof_ksp_rtol 1e-6\
544:           -snes_converged_reason -snes_monitor -snes_rtol 1e-9 -snes_stol 1e-9\
545:           -ts_dt 0.1 -ts_exact_final_time stepover -ts_max_snes_failures -1 -ts_max_steps 1 -ts_monitor -ts_type beuler -info :vec

547:     test:
548:       suffix: cpu_3d
549:       args: -dm_landau_device_type cpu
550:     test:
551:       suffix: kokkos_3d
552:       requires: kokkos_kernels
553:       args: -dm_landau_device_type kokkos -dm_mat_type aijkokkos -dm_vec_type kokkos
554:     test:
555:       suffix: cuda_3d
556:       requires: cuda
557:       args: -dm_landau_device_type cuda -dm_mat_type aijcusparse -dm_vec_type cuda

559: TEST*/