Actual source code: swarm_ex3.c
2: static char help[] = "Tests DMSwarm with DMShell\n\n";
4: #include <petscsf.h>
5: #include <petscdm.h>
6: #include <petscdmshell.h>
7: #include <petscdmda.h>
8: #include <petscdmswarm.h>
9: #include <petsc/private/dmimpl.h>
11: PetscErrorCode _DMLocatePoints_DMDARegular_IS(DM dm, Vec pos, IS *iscell)
12: {
13: PetscInt p, n, bs, npoints, si, sj, milocal, mjlocal, mx, my;
14: DM dmregular;
15: PetscInt *cellidx;
16: const PetscScalar *coor;
17: PetscReal dx, dy;
18: PetscMPIInt rank;
20: PetscFunctionBegin;
21: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
22: PetscCall(VecGetLocalSize(pos, &n));
23: PetscCall(VecGetBlockSize(pos, &bs));
24: npoints = n / bs;
26: PetscCall(PetscMalloc1(npoints, &cellidx));
27: PetscCall(DMGetApplicationContext(dm, &dmregular));
28: PetscCall(DMDAGetCorners(dmregular, &si, &sj, NULL, &milocal, &mjlocal, NULL));
29: PetscCall(DMDAGetInfo(dmregular, NULL, &mx, &my, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL));
31: dx = 2.0 / ((PetscReal)mx);
32: dy = 2.0 / ((PetscReal)my);
34: PetscCall(VecGetArrayRead(pos, &coor));
35: for (p = 0; p < npoints; p++) {
36: PetscReal coorx, coory;
37: PetscInt mi, mj;
39: coorx = PetscRealPart(coor[2 * p]);
40: coory = PetscRealPart(coor[2 * p + 1]);
42: mi = (PetscInt)((coorx - (-1.0)) / dx);
43: mj = (PetscInt)((coory - (-1.0)) / dy);
45: cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
47: if ((mj >= sj) && (mj < sj + mjlocal)) {
48: if ((mi >= si) && (mi < si + milocal)) cellidx[p] = (mi - si) + (mj - sj) * milocal;
49: }
50: if (coorx < -1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
51: if (coorx > 1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
52: if (coory < -1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
53: if (coory > 1.0) cellidx[p] = DMLOCATEPOINT_POINT_NOT_FOUND;
54: }
55: PetscCall(VecRestoreArrayRead(pos, &coor));
56: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, npoints, cellidx, PETSC_OWN_POINTER, iscell));
57: PetscFunctionReturn(PETSC_SUCCESS);
58: }
60: PetscErrorCode DMLocatePoints_DMDARegular(DM dm, Vec pos, DMPointLocationType ltype, PetscSF cellSF)
61: {
62: IS iscell;
63: PetscSFNode *cells;
64: PetscInt p, bs, npoints, nfound;
65: const PetscInt *boxCells;
67: PetscFunctionBegin;
68: PetscCall(_DMLocatePoints_DMDARegular_IS(dm, pos, &iscell));
69: PetscCall(VecGetLocalSize(pos, &npoints));
70: PetscCall(VecGetBlockSize(pos, &bs));
71: npoints = npoints / bs;
73: PetscCall(PetscMalloc1(npoints, &cells));
74: PetscCall(ISGetIndices(iscell, &boxCells));
76: for (p = 0; p < npoints; p++) {
77: cells[p].rank = 0;
78: cells[p].index = DMLOCATEPOINT_POINT_NOT_FOUND;
79: cells[p].index = boxCells[p];
80: }
81: PetscCall(ISRestoreIndices(iscell, &boxCells));
82: PetscCall(ISDestroy(&iscell));
83: nfound = npoints;
84: PetscCall(PetscSFSetGraph(cellSF, npoints, nfound, NULL, PETSC_OWN_POINTER, cells, PETSC_OWN_POINTER));
85: PetscCall(ISDestroy(&iscell));
86: PetscFunctionReturn(PETSC_SUCCESS);
87: }
89: PetscErrorCode DMGetNeighbors_DMDARegular(DM dm, PetscInt *nneighbors, const PetscMPIInt **neighbors)
90: {
91: DM dmregular;
93: PetscFunctionBegin;
94: PetscCall(DMGetApplicationContext(dm, &dmregular));
95: PetscCall(DMGetNeighbors(dmregular, nneighbors, neighbors));
96: PetscFunctionReturn(PETSC_SUCCESS);
97: }
99: PetscErrorCode SwarmViewGP(DM dms, const char prefix[])
100: {
101: PetscReal *array;
102: PetscInt *iarray;
103: PetscInt npoints, p, bs;
104: FILE *fp;
105: char name[PETSC_MAX_PATH_LEN];
106: PetscMPIInt rank;
108: PetscFunctionBegin;
109: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
110: PetscCall(PetscSNPrintf(name, PETSC_MAX_PATH_LEN - 1, "%s-rank%d.gp", prefix, rank));
111: fp = fopen(name, "w");
112: PetscCheck(fp, PETSC_COMM_SELF, PETSC_ERR_FILE_OPEN, "Cannot open file %s", name);
113: PetscCall(DMSwarmGetLocalSize(dms, &npoints));
114: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
115: PetscCall(DMSwarmGetField(dms, "itag", NULL, NULL, (void **)&iarray));
116: 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]);
117: PetscCall(DMSwarmRestoreField(dms, "itag", NULL, NULL, (void **)&iarray));
118: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
119: fclose(fp);
120: PetscFunctionReturn(PETSC_SUCCESS);
121: }
123: /*
124: Create a DMShell and attach a regularly spaced DMDA for point location
125: Override methods for point location
126: */
127: PetscErrorCode ex3_1(void)
128: {
129: DM dms, dmcell, dmregular;
130: PetscMPIInt rank;
131: PetscInt p, bs, nlocal, overlap, mx, tk;
132: PetscReal dx;
133: PetscReal *array, dt;
134: PetscInt *iarray;
135: PetscRandom rand;
137: PetscFunctionBegin;
138: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
140: /* Create a regularly spaced DMDA */
141: mx = 40;
142: overlap = 0;
143: 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));
144: PetscCall(DMSetFromOptions(dmregular));
145: PetscCall(DMSetUp(dmregular));
147: dx = 2.0 / ((PetscReal)mx);
148: 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));
150: /* Create a DMShell for point location purposes */
151: PetscCall(DMShellCreate(PETSC_COMM_WORLD, &dmcell));
152: PetscCall(DMSetApplicationContext(dmcell, dmregular));
153: dmcell->ops->locatepoints = DMLocatePoints_DMDARegular;
154: dmcell->ops->getneighbors = DMGetNeighbors_DMDARegular;
156: /* Create the swarm */
157: PetscCall(DMCreate(PETSC_COMM_WORLD, &dms));
158: PetscCall(DMSetType(dms, DMSWARM));
159: PetscCall(DMSetDimension(dms, 2));
160: PetscCall(PetscObjectSetName((PetscObject)dms, "Particles"));
162: PetscCall(DMSwarmSetType(dms, DMSWARM_PIC));
163: PetscCall(DMSwarmSetCellDM(dms, dmcell));
165: PetscCall(DMSwarmRegisterPetscDatatypeField(dms, "itag", 1, PETSC_INT));
166: PetscCall(DMSwarmFinalizeFieldRegister(dms));
167: {
168: PetscInt si, sj, milocal, mjlocal;
169: const PetscScalar *LA_coors;
170: Vec coors;
171: PetscInt cnt;
173: PetscCall(DMDAGetCorners(dmregular, &si, &sj, NULL, &milocal, &mjlocal, NULL));
174: PetscCall(DMGetCoordinates(dmregular, &coors));
175: PetscCall(VecGetArrayRead(coors, &LA_coors));
176: PetscCall(DMSwarmSetLocalSizes(dms, milocal * mjlocal, 4));
177: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
178: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
179: cnt = 0;
180: PetscCall(PetscRandomCreate(PETSC_COMM_SELF, &rand));
181: PetscCall(PetscRandomSetInterval(rand, -1.0, 1.0));
182: for (p = 0; p < nlocal; p++) {
183: PetscReal px, py, rx, ry, r2;
185: PetscCall(PetscRandomGetValueReal(rand, &rx));
186: PetscCall(PetscRandomGetValueReal(rand, &ry));
188: px = PetscRealPart(LA_coors[2 * p + 0]) + 0.1 * rx * dx;
189: py = PetscRealPart(LA_coors[2 * p + 1]) + 0.1 * ry * dx;
191: r2 = px * px + py * py;
192: if (r2 < 0.75 * 0.75) {
193: array[bs * cnt + 0] = px;
194: array[bs * cnt + 1] = py;
195: cnt++;
196: }
197: }
198: PetscCall(PetscRandomDestroy(&rand));
199: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
200: PetscCall(VecRestoreArrayRead(coors, &LA_coors));
201: PetscCall(DMSwarmSetLocalSizes(dms, cnt, 4));
203: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
204: PetscCall(DMSwarmGetField(dms, "itag", &bs, NULL, (void **)&iarray));
205: for (p = 0; p < nlocal; p++) iarray[p] = (PetscInt)rank;
206: PetscCall(DMSwarmRestoreField(dms, "itag", &bs, NULL, (void **)&iarray));
207: }
209: PetscCall(DMView(dms, PETSC_VIEWER_STDOUT_WORLD));
210: PetscCall(SwarmViewGP(dms, "step0"));
212: dt = 0.1;
213: for (tk = 1; tk < 20; tk++) {
214: char prefix[PETSC_MAX_PATH_LEN];
215: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Step %" PetscInt_FMT " \n", tk));
216: /* push points */
217: PetscCall(DMSwarmGetLocalSize(dms, &nlocal));
218: PetscCall(DMSwarmGetField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
219: for (p = 0; p < nlocal; p++) {
220: PetscReal cx, cy, vx, vy;
222: cx = array[2 * p];
223: cy = array[2 * p + 1];
224: vx = cy;
225: vy = -cx;
227: array[2 * p] += dt * vx;
228: array[2 * p + 1] += dt * vy;
229: }
230: PetscCall(DMSwarmRestoreField(dms, DMSwarmPICField_coor, &bs, NULL, (void **)&array));
232: /* migrate points */
233: PetscCall(DMSwarmMigrate(dms, PETSC_TRUE));
234: /* view points */
235: PetscCall(PetscSNPrintf(prefix, PETSC_MAX_PATH_LEN - 1, "step%" PetscInt_FMT, tk));
236: /* should use the regular SwarmView() api, not one for a particular type */
237: PetscCall(SwarmViewGP(dms, prefix));
238: }
239: PetscCall(DMDestroy(&dmregular));
240: PetscCall(DMDestroy(&dmcell));
241: PetscCall(DMDestroy(&dms));
242: PetscFunctionReturn(PETSC_SUCCESS);
243: }
245: int main(int argc, char **argv)
246: {
247: PetscFunctionBeginUser;
248: PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
249: PetscCall(ex3_1());
250: PetscCall(PetscFinalize());
251: return 0;
252: }
254: /*TEST
256: build:
257: requires: double !complex
259: test:
260: filter: grep -v atomic
261: filter_output: grep -v atomic
262: TEST*/