Actual source code: ex3.c
1: static char help[] = "Example usage of extracting single cells with their associated fields from a swarm and putting it in a new swarm object\n";
3: #include <petscdmplex.h>
4: #include <petscdmswarm.h>
5: #include <petscts.h>
7: typedef struct {
8: PetscInt particlesPerCell; /* The number of partices per cell */
9: } AppCtx;
11: static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
12: {
13: PetscFunctionBeginUser;
14: options->particlesPerCell = 1;
16: PetscOptionsBegin(comm, "", "CellSwarm Options", "DMSWARM");
17: PetscCall(PetscOptionsInt("-particles_per_cell", "Number of particles per cell", "ex3.c", options->particlesPerCell, &options->particlesPerCell, NULL));
18: PetscOptionsEnd();
19: PetscFunctionReturn(PETSC_SUCCESS);
20: }
22: static PetscErrorCode CreateMesh(MPI_Comm comm, DM *dm, AppCtx *user)
23: {
24: PetscFunctionBeginUser;
25: PetscCall(DMCreate(comm, dm));
26: PetscCall(DMSetType(*dm, DMPLEX));
27: PetscCall(DMSetFromOptions(*dm));
28: PetscCall(DMViewFromOptions(*dm, NULL, "-dm_view"));
29: PetscFunctionReturn(PETSC_SUCCESS);
30: }
32: static PetscErrorCode CreateParticles(DM dm, DM *sw, AppCtx *user)
33: {
34: PetscInt *cellid;
35: PetscInt dim, cStart, cEnd, c, Np = user->particlesPerCell, p;
37: PetscFunctionBeginUser;
38: PetscCall(DMGetDimension(dm, &dim));
39: PetscCall(DMCreate(PetscObjectComm((PetscObject)dm), sw));
40: PetscCall(DMSetType(*sw, DMSWARM));
41: PetscCall(DMSetDimension(*sw, dim));
42: PetscCall(DMSwarmSetType(*sw, DMSWARM_PIC));
43: PetscCall(DMSwarmSetCellDM(*sw, dm));
44: PetscCall(DMSwarmRegisterPetscDatatypeField(*sw, "kinematics", 2, PETSC_REAL));
45: PetscCall(DMSwarmFinalizeFieldRegister(*sw));
46: PetscCall(DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd));
47: PetscCall(DMSwarmSetLocalSizes(*sw, (cEnd - cStart) * Np, 0));
48: PetscCall(DMSetFromOptions(*sw));
49: PetscCall(DMSwarmGetField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **)&cellid));
50: for (c = cStart; c < cEnd; ++c) {
51: for (p = 0; p < Np; ++p) {
52: const PetscInt n = c * Np + p;
54: cellid[n] = c;
55: }
56: }
57: PetscCall(DMSwarmRestoreField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **)&cellid));
58: PetscCall(PetscObjectSetName((PetscObject)*sw, "Particles"));
59: PetscCall(DMViewFromOptions(*sw, NULL, "-sw_view"));
60: PetscFunctionReturn(PETSC_SUCCESS);
61: }
63: int main(int argc, char **argv)
64: {
65: DM dm, sw, cellsw; /* Mesh and particle managers */
66: MPI_Comm comm;
67: AppCtx user;
69: PetscFunctionBeginUser;
70: PetscCall(PetscInitialize(&argc, &argv, NULL, help));
71: comm = PETSC_COMM_WORLD;
72: PetscCall(ProcessOptions(comm, &user));
73: PetscCall(CreateMesh(comm, &dm, &user));
74: PetscCall(CreateParticles(dm, &sw, &user));
75: PetscCall(DMSetApplicationContext(sw, &user));
76: PetscCall(DMCreate(comm, &cellsw));
77: PetscCall(PetscObjectSetName((PetscObject)cellsw, "SubParticles"));
78: PetscCall(DMSwarmGetCellSwarm(sw, 1, cellsw));
79: PetscCall(DMViewFromOptions(cellsw, NULL, "-subswarm_view"));
80: PetscCall(DMSwarmRestoreCellSwarm(sw, 1, cellsw));
81: PetscCall(DMDestroy(&sw));
82: PetscCall(DMDestroy(&dm));
83: PetscCall(DMDestroy(&cellsw));
84: PetscCall(PetscFinalize());
85: return 0;
86: }
88: /*TEST
89: build:
90: requires: triangle !single !complex
91: test:
92: suffix: 1
93: args: -particles_per_cell 2 -dm_plex_box_faces 2,1 -dm_view -sw_view -subswarm_view
94: TEST*/