Actual source code: swarm_ex3.c
1: static char help[] = "Tests DMSwarm with DMShell\n\n";
3: #include <petscsf.h>
4: #include <petscdm.h>
5: #include <petscdmshell.h>
6: #include <petscdmda.h>
7: #include <petscdmswarm.h>
8: #include <petsc/private/dmimpl.h>
10: PetscErrorCode _DMLocatePoints_DMDARegular_IS(DM dm, Vec pos, IS *iscell)
11: {
12: PetscInt p, n, bs, npoints, si, sj, milocal, mjlocal, mx, my;
13: DM dmregular;
14: PetscInt *cellidx;
15: const PetscScalar *coor;
16: PetscReal dx, dy;
17: PetscMPIInt rank;
19: PetscFunctionBegin;
20: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
21: PetscCall(VecGetLocalSize(pos, &n));
22: PetscCall(VecGetBlockSize(pos, &bs));
23: npoints = n / bs;
25: PetscCall(PetscMalloc1(npoints, &cellidx));
26: PetscCall(DMGetApplicationContext(dm, &dmregular));
27: PetscCall(DMDAGetCorners(dmregular, &si, &sj, NULL, &milocal, &mjlocal, NULL));
28: PetscCall(DMDAGetInfo(dmregular, NULL, &mx, &my, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL));
30: dx = 2.0 / ((PetscReal)mx);
31: dy = 2.0 / ((PetscReal)my);
33: PetscCall(VecGetArrayRead(pos, &coor));
34: for (p = 0; p < npoints; p++) {
35: PetscReal coorx, coory;
36: PetscInt mi, mj;
38: coorx = PetscRealPart(coor[2 * p]);
39: coory = PetscRealPart(coor[2 * p + 1]);
41: mi = (PetscInt)((coorx - (-1.0)) / dx);
42: mj = (PetscInt)((coory - (-1.0)) / dy);
44: cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
46: if ((mj >= sj) && (mj < sj + mjlocal)) {
47: if ((mi >= si) && (mi < si + milocal)) cellidx[p] = (mi - si) + (mj - sj) * milocal;
48: }
49: if (coorx < -1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
50: if (coorx > 1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
51: if (coory < -1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
52: if (coory > 1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
53: }
54: PetscCall(VecRestoreArrayRead(pos, &coor));
55: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, npoints, cellidx, PETSC_OWN_POINTER, iscell));
56: PetscFunctionReturn(PETSC_SUCCESS);
57: }
59: PetscErrorCode DMLocatePoints_DMDARegular(DM dm, Vec pos, DMPointLocationType ltype, PetscSF cellSF)
60: {
61: IS iscell;
62: PetscSFNode *cells;
63: PetscInt p, bs, npoints, nfound;
64: const PetscInt *boxCells;
66: PetscFunctionBegin;
67: PetscCall(_DMLocatePoints_DMDARegular_IS(dm, pos, &iscell));
68: PetscCall(VecGetLocalSize(pos, &npoints));
69: PetscCall(VecGetBlockSize(pos, &bs));
70: npoints = npoints / bs;
72: PetscCall(PetscMalloc1(npoints, &cells));
73: PetscCall(ISGetIndices(iscell, &boxCells));
75: for (p = 0; p < npoints; p++) {
76: cells[p].rank = 0;
77: cells[p].index = DMLOCATEPOINT_POINT_NOT_FOUND;
78: cells[p].index = boxCells[p];
79: }
80: PetscCall(ISRestoreIndices(iscell, &boxCells));
81: PetscCall(ISDestroy(&iscell));
82: nfound = npoints;
83: PetscCall(PetscSFSetGraph(cellSF, npoints, nfound, NULL, PETSC_OWN_POINTER, cells, PETSC_OWN_POINTER));
84: PetscCall(ISDestroy(&iscell));
85: PetscFunctionReturn(PETSC_SUCCESS);
86: }
88: PetscErrorCode DMGetNeighbors_DMDARegular(DM dm, PetscInt *nneighbors, const PetscMPIInt **neighbors)
89: {
90: DM dmregular;
92: PetscFunctionBegin;
93: PetscCall(DMGetApplicationContext(dm, &dmregular));
94: PetscCall(DMGetNeighbors(dmregular, nneighbors, neighbors));
95: PetscFunctionReturn(PETSC_SUCCESS);
96: }
98: PetscErrorCode SwarmViewGP(DM dms, const char prefix[])
99: {
100: PetscReal *array;
101: PetscInt *iarray;
102: PetscInt npoints, p, bs;
103: FILE *fp;
104: char name[PETSC_MAX_PATH_LEN];
105: PetscMPIInt rank;
107: PetscFunctionBegin;
108: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
109: PetscCall(PetscSNPrintf(name, PETSC_MAX_PATH_LEN - 1, "%s-rank%d.gp", prefix, rank));
110: fp = fopen(name, "w");
111: PetscCheck(fp, PETSC_COMM_SELF, PETSC_ERR_FILE_OPEN, "Cannot open file %s", name);
112: PetscCall(DMSwarmGetLocalSize(dms, &npoints));
113: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
114: PetscCall(DMSwarmGetField(dms, "itag", NULL, NULL, (void **)&iarray));
115: for (p = 0; p < npoints; p++) fprintf(fp, "%+1.4e %+1.4e %1.4e\n", array[2 * p], array[2 * p + 1], (double)iarray[p]);
116: PetscCall(DMSwarmRestoreField(dms, "itag", NULL, NULL, (void **)&iarray));
117: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
118: fclose(fp);
119: PetscFunctionReturn(PETSC_SUCCESS);
120: }
122: /*
123: Create a DMShell and attach a regularly spaced DMDA for point location
124: Override methods for point location
125: */
126: PetscErrorCode ex3_1(void)
127: {
128: DM dms, dmcell, dmregular;
129: PetscMPIInt rank;
130: PetscInt p, bs, nlocal, overlap, mx, tk;
131: PetscReal dx;
132: PetscReal *array, dt;
133: PetscInt *iarray;
134: PetscRandom rand;
136: PetscFunctionBegin;
137: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
139: /* Create a regularly spaced DMDA */
140: mx = 40;
141: overlap = 0;
142: PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_BOX, mx, mx, PETSC_DECIDE, PETSC_DECIDE, 1, overlap, NULL, NULL, &dmregular));
143: PetscCall(DMSetFromOptions(dmregular));
144: PetscCall(DMSetUp(dmregular));
146: dx = 2.0 / ((PetscReal)mx);
147: PetscCall(DMDASetUniformCoordinates(dmregular, -1.0 + 0.5 * dx, 1.0 - 0.5 * dx, -1.0 + 0.5 * dx, 1.0 - 0.5 * dx, -1.0, 1.0));
149: /* Create a DMShell for point location purposes */
150: PetscCall(DMShellCreate(PETSC_COMM_WORLD, &dmcell));
151: PetscCall(DMSetApplicationContext(dmcell, dmregular));
152: dmcell->ops->locatepoints = DMLocatePoints_DMDARegular;
153: dmcell->ops->getneighbors = DMGetNeighbors_DMDARegular;
155: /* Create the swarm */
156: PetscCall(DMCreate(PETSC_COMM_WORLD, &dms));
157: PetscCall(DMSetType(dms, DMSWARM));
158: PetscCall(DMSetDimension(dms, 2));
159: PetscCall(PetscObjectSetName((PetscObject)dms, "Particles"));
161: PetscCall(DMSwarmSetType(dms, DMSWARM_PIC));
162: PetscCall(DMSwarmSetCellDM(dms, dmcell));
164: PetscCall(DMSwarmRegisterPetscDatatypeField(dms, "itag", 1, PETSC_INT));
165: PetscCall(DMSwarmFinalizeFieldRegister(dms));
166: {
167: PetscInt si, sj, milocal, mjlocal;
168: const PetscScalar *LA_coors;
169: Vec coors;
170: PetscInt cnt;
172: PetscCall(DMDAGetCorners(dmregular, &si, &sj, NULL, &milocal, &mjlocal, NULL));
173: PetscCall(DMGetCoordinates(dmregular, &coors));
174: PetscCall(VecGetArrayRead(coors, &LA_coors));
175: PetscCall(DMSwarmSetLocalSizes(dms, milocal * mjlocal, 4));
176: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
177: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
178: cnt = 0;
179: PetscCall(PetscRandomCreate(PETSC_COMM_SELF, &rand));
180: PetscCall(PetscRandomSetInterval(rand, -1.0, 1.0));
181: for (p = 0; p < nlocal; p++) {
182: PetscReal px, py, rx, ry, r2;
184: PetscCall(PetscRandomGetValueReal(rand, &rx));
185: PetscCall(PetscRandomGetValueReal(rand, &ry));
187: px = PetscRealPart(LA_coors[2 * p + 0]) + 0.1 * rx * dx;
188: py = PetscRealPart(LA_coors[2 * p + 1]) + 0.1 * ry * dx;
190: r2 = px * px + py * py;
191: if (r2 < 0.75 * 0.75) {
192: array[bs * cnt + 0] = px;
193: array[bs * cnt + 1] = py;
194: cnt++;
195: }
196: }
197: PetscCall(PetscRandomDestroy(&rand));
198: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
199: PetscCall(VecRestoreArrayRead(coors, &LA_coors));
200: PetscCall(DMSwarmSetLocalSizes(dms, cnt, 4));
202: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
203: PetscCall(DMSwarmGetField(dms, "itag", &bs, NULL, (void **)&iarray));
204: for (p = 0; p < nlocal; p++) iarray[p] = (PetscInt)rank;
205: PetscCall(DMSwarmRestoreField(dms, "itag", &bs, NULL, (void **)&iarray));
206: }
208: PetscCall(DMView(dms, PETSC_VIEWER_STDOUT_WORLD));
209: PetscCall(SwarmViewGP(dms, "step0"));
211: dt = 0.1;
212: for (tk = 1; tk < 20; tk++) {
213: char prefix[PETSC_MAX_PATH_LEN];
214: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Step %" PetscInt_FMT " \n", tk));
215: /* push points */
216: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
217: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
218: for (p = 0; p < nlocal; p++) {
219: PetscReal cx, cy, vx, vy;
221: cx = array[2 * p];
222: cy = array[2 * p + 1];
223: vx = cy;
224: vy = -cx;
226: array[2 * p] += dt * vx;
227: array[2 * p + 1] += dt * vy;
228: }
229: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
231: /* migrate points */
232: PetscCall(DMSwarmMigrate(dms, PETSC_TRUE));
233: /* view points */
234: PetscCall(PetscSNPrintf(prefix, PETSC_MAX_PATH_LEN - 1, "step%" PetscInt_FMT, tk));
235: /* should use the regular SwarmView() api, not one for a particular type */
236: PetscCall(SwarmViewGP(dms, prefix));
237: }
238: PetscCall(DMDestroy(&dmregular));
239: PetscCall(DMDestroy(&dmcell));
240: PetscCall(DMDestroy(&dms));
241: PetscFunctionReturn(PETSC_SUCCESS);
242: }
244: int main(int argc, char **argv)
245: {
246: PetscFunctionBeginUser;
247: PetscCall(PetscInitialize(&argc, &argv, NULL, help));
248: PetscCall(ex3_1());
249: PetscCall(PetscFinalize());
250: return 0;
251: }
253: /*TEST
255: build:
256: requires: double !complex
258: test:
259: filter: grep -v atomic
260: filter_output: grep -v atomic
261: TEST*/