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"; 2 3 #include <petscdmplex.h> 4 #include <petscdmswarm.h> 5 #include <petscts.h> 6 7 typedef struct { 8 PetscInt particlesPerCell; /* The number of partices per cell */ 9 } AppCtx; 10 11 static PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options) { 12 PetscFunctionBeginUser; 13 options->particlesPerCell = 1; 14 15 PetscOptionsBegin(comm, "", "CellSwarm Options", "DMSWARM"); 16 PetscCall(PetscOptionsInt("-particles_per_cell", "Number of particles per cell", "ex3.c", options->particlesPerCell, &options->particlesPerCell, NULL)); 17 PetscOptionsEnd(); 18 PetscFunctionReturn(0); 19 } 20 21 static PetscErrorCode CreateMesh(MPI_Comm comm, DM *dm, AppCtx *user) { 22 PetscFunctionBeginUser; 23 PetscCall(DMCreate(comm, dm)); 24 PetscCall(DMSetType(*dm, DMPLEX)); 25 PetscCall(DMSetFromOptions(*dm)); 26 PetscCall(DMViewFromOptions(*dm, NULL, "-dm_view")); 27 PetscFunctionReturn(0); 28 } 29 30 static PetscErrorCode CreateParticles(DM dm, DM *sw, AppCtx *user) { 31 PetscInt *cellid; 32 PetscInt dim, cStart, cEnd, c, Np = user->particlesPerCell, p; 33 34 PetscFunctionBeginUser; 35 PetscCall(DMGetDimension(dm, &dim)); 36 PetscCall(DMCreate(PetscObjectComm((PetscObject)dm), sw)); 37 PetscCall(DMSetType(*sw, DMSWARM)); 38 PetscCall(DMSetDimension(*sw, dim)); 39 PetscCall(DMSwarmSetType(*sw, DMSWARM_PIC)); 40 PetscCall(DMSwarmSetCellDM(*sw, dm)); 41 PetscCall(DMSwarmRegisterPetscDatatypeField(*sw, "kinematics", 2, PETSC_REAL)); 42 PetscCall(DMSwarmFinalizeFieldRegister(*sw)); 43 PetscCall(DMPlexGetHeightStratum(dm, 0, &cStart, &cEnd)); 44 PetscCall(DMSwarmSetLocalSizes(*sw, (cEnd - cStart) * Np, 0)); 45 PetscCall(DMSetFromOptions(*sw)); 46 PetscCall(DMSwarmGetField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **)&cellid)); 47 for (c = cStart; c < cEnd; ++c) { 48 for (p = 0; p < Np; ++p) { 49 const PetscInt n = c * Np + p; 50 51 cellid[n] = c; 52 } 53 } 54 PetscCall(DMSwarmRestoreField(*sw, DMSwarmPICField_cellid, NULL, NULL, (void **)&cellid)); 55 PetscCall(PetscObjectSetName((PetscObject)*sw, "Particles")); 56 PetscCall(DMViewFromOptions(*sw, NULL, "-sw_view")); 57 PetscFunctionReturn(0); 58 } 59 60 int main(int argc, char **argv) { 61 DM dm, sw, cellsw; /* Mesh and particle managers */ 62 MPI_Comm comm; 63 AppCtx user; 64 65 PetscFunctionBeginUser; 66 PetscCall(PetscInitialize(&argc, &argv, NULL, help)); 67 comm = PETSC_COMM_WORLD; 68 PetscCall(ProcessOptions(comm, &user)); 69 PetscCall(CreateMesh(comm, &dm, &user)); 70 PetscCall(CreateParticles(dm, &sw, &user)); 71 PetscCall(DMSetApplicationContext(sw, &user)); 72 PetscCall(DMCreate(comm, &cellsw)); 73 PetscCall(PetscObjectSetName((PetscObject)cellsw, "SubParticles")); 74 PetscCall(DMSwarmGetCellSwarm(sw, 1, cellsw)); 75 PetscCall(DMViewFromOptions(cellsw, NULL, "-subswarm_view")); 76 PetscCall(DMSwarmRestoreCellSwarm(sw, 1, cellsw)); 77 PetscCall(DMDestroy(&sw)); 78 PetscCall(DMDestroy(&dm)); 79 PetscCall(DMDestroy(&cellsw)); 80 PetscCall(PetscFinalize()); 81 return 0; 82 } 83 84 /*TEST 85 build: 86 requires: triangle !single !complex 87 test: 88 suffix: 1 89 args: -particles_per_cell 2 -dm_plex_box_faces 2,1 -dm_view -sw_view -subswarm_view 90 TEST*/ 91