Actual source code: ex2.c

  1: static char help[] = "Test DMCreateCoordinateDM_Network, and related functions \n\n";

  3: #include <petscdmnetwork.h>

  5: /*
  6: CreateStarGraphEdgeList - Create a k-Star Graph Edgelist on current processor
  7:   Not Collective

  9:   Input Parameters:
 10: . k    - order of the star graph (number of edges)
 11: . directin - if true direction of edges is towards the center vertex, otherwise they are directed out of the center vertex.

 13:   Output Parameters:
 14: .  ne - number of edges of this star graph
 15: .  edgelist - list of edges for this star graph, this is a one dimensional array with pairs of entries being the two vertices (in global numbering of the vertices) of each edge,
 16:               [first vertex of first edge, second vertex of first edge, first vertex of second edge, second vertex of second edge, etc].

 18:               User is responsible for deallocating this memory.
 19: */
 20: PetscErrorCode StarGraphCreateEdgeList(PetscInt k, PetscBool directin, PetscInt *ne, PetscInt *edgelist[])
 21: {
 22:   PetscInt i;

 24:   PetscFunctionBegin;
 25:   *ne = k;
 26:   PetscCall(PetscCalloc1(2 * k, edgelist));

 28:   if (directin) {
 29:     for (i = 0; i < k; i++) {
 30:       (*edgelist)[2 * i]     = i + 1;
 31:       (*edgelist)[2 * i + 1] = 0;
 32:     }
 33:   } else {
 34:     for (i = 0; i < k; i++) {
 35:       (*edgelist)[2 * i]     = 0;
 36:       (*edgelist)[2 * i + 1] = i + 1;
 37:     }
 38:   }
 39:   PetscFunctionReturn(PETSC_SUCCESS);
 40: }

 42: /*
 43: CreateSimpleStarGraph - Create a Distributed k-Star Graph DMNetwork with a single PetscInt component on
 44: all edges and vertices, a selectable number of dofs on vertices and edges. Intended mostly to be used for testing purposes.

 46:   Input Parameters:
 47: . comm       - the communicator of the dm
 48: . numdofvert - number of degrees of freedom (dofs) on vertices
 49: . numdofedge - number of degrees of freedom (dofs) on edges
 50: . k          - order of the star graph (number of edges)
 51: . directin   - if true direction of edges is towards the center vertex, otherwise they are directed out of the center vertex

 53:   Output Parameter:
 54: . newdm       - The created and distributed simple Star Graph
 55: */
 56: PetscErrorCode StarGraphCreate(MPI_Comm comm, PetscInt numdofvert, PetscInt numdofedge, PetscInt k, PetscBool directin, DM *newdm)
 57: {
 58:   DM          dm;
 59:   PetscMPIInt rank;
 60:   PetscInt    ne       = 0, compkey, eStart, eEnd, vStart, vEnd, e, v;
 61:   PetscInt   *edgelist = NULL, *compedge, *compvert;

 63:   PetscFunctionBegin;
 64:   PetscCall(DMNetworkCreate(comm, &dm));
 65:   PetscCall(DMNetworkSetNumSubNetworks(dm, PETSC_DECIDE, 1));
 66:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
 67:   if (rank == 0) PetscCall(StarGraphCreateEdgeList(k, directin, &ne, &edgelist));
 68:   PetscCall(DMNetworkAddSubnetwork(dm, "Main", ne, edgelist, NULL));
 69:   PetscCall(DMNetworkRegisterComponent(dm, "dummy", sizeof(PetscInt), &compkey));
 70:   PetscCall(DMNetworkLayoutSetUp(dm));
 71:   PetscCall(PetscFree(edgelist));
 72:   PetscCall(DMNetworkGetEdgeRange(dm, &eStart, &eEnd));
 73:   PetscCall(DMNetworkGetVertexRange(dm, &vStart, &vEnd));
 74:   PetscCall(PetscMalloc2(eEnd - eStart, &compedge, vEnd - vStart, &compvert));
 75:   for (e = eStart; e < eEnd; e++) {
 76:     compedge[e - eStart] = e;
 77:     PetscCall(DMNetworkAddComponent(dm, e, compkey, &compedge[e - eStart], numdofedge));
 78:   }
 79:   for (v = vStart; v < vEnd; v++) {
 80:     compvert[v - vStart] = v;
 81:     PetscCall(DMNetworkAddComponent(dm, v, compkey, &compvert[v - vStart], numdofvert));
 82:   }
 83:   PetscCall(DMSetFromOptions(dm));
 84:   PetscCall(DMSetUp(dm));
 85:   PetscCall(PetscFree2(compedge, compvert));
 86:   *newdm = dm;
 87:   PetscFunctionReturn(PETSC_SUCCESS);
 88: }

 90: /* Simple Circular embedding of the star graph */
 91: PetscErrorCode StarGraphSetCoordinates(DM dm)
 92: {
 93:   DM           cdm;
 94:   Vec          Coord;
 95:   PetscScalar *coord;
 96:   PetscInt     vStart, vEnd, v, vglobal, compkey, off, NVert;
 97:   PetscReal    theta;

 99:   PetscFunctionBegin;
100:   PetscCall(DMGetCoordinateDM(dm, &cdm));
101:   PetscCall(DMSetCoordinateDim(dm, 2));
102:   PetscCall(DMNetworkGetVertexRange(cdm, &vStart, &vEnd));
103:   PetscCall(DMNetworkRegisterComponent(cdm, "coordinates", 0, &compkey));
104:   for (v = vStart; v < vEnd; v++) PetscCall(DMNetworkAddComponent(cdm, v, compkey, NULL, 2));
105:   PetscCall(DMNetworkFinalizeComponents(cdm));

107:   PetscCall(DMCreateLocalVector(cdm, &Coord));
108:   PetscCall(VecGetArray(Coord, &coord));
109:   PetscCall(DMNetworkGetNumVertices(cdm, NULL, &NVert));
110:   theta = 2 * PETSC_PI / (NVert - 1);
111:   for (v = vStart; v < vEnd; v++) {
112:     PetscCall(DMNetworkGetGlobalVertexIndex(cdm, v, &vglobal));
113:     PetscCall(DMNetworkGetLocalVecOffset(cdm, v, 0, &off));
114:     if (vglobal == 0) {
115:       coord[off]     = 0.0;
116:       coord[off + 1] = 0.0;
117:     } else {
118:       /* embed on the unit circle */
119:       coord[off]     = PetscCosReal(theta * (vglobal - 1));
120:       coord[off + 1] = PetscSinReal(theta * (vglobal - 1));
121:     }
122:   }
123:   PetscCall(VecRestoreArray(Coord, &coord));
124:   PetscCall(DMSetCoordinatesLocal(dm, Coord));
125:   PetscCall(VecDestroy(&Coord));
126:   PetscFunctionReturn(PETSC_SUCCESS);
127: }

129: /* This subroutine is used in petsc/src/snes/tutorials/network/ex1.c */
130: static PetscErrorCode CoordinatePrint(DM dm)
131: {
132:   DM                 dmclone;
133:   PetscInt           cdim, v, off, vglobal, vStart, vEnd;
134:   const PetscScalar *carray;
135:   Vec                coords;
136:   MPI_Comm           comm;
137:   PetscMPIInt        rank;

139:   PetscFunctionBegin;
140:   PetscCall(PetscObjectGetComm((PetscObject)dm, &comm));
141:   PetscCallMPI(MPI_Comm_rank(comm, &rank));

143:   PetscCall(DMGetCoordinateDM(dm, &dmclone));
144:   PetscCall(DMNetworkGetVertexRange(dm, &vStart, &vEnd));
145:   PetscCall(DMGetCoordinatesLocal(dm, &coords));

147:   PetscCall(DMGetCoordinateDim(dm, &cdim));
148:   PetscCall(VecGetArrayRead(coords, &carray));

150:   PetscCall(PetscPrintf(MPI_COMM_WORLD, "\nCoordinatePrint, cdim %" PetscInt_FMT ":\n", cdim));
151:   PetscCall(PetscSynchronizedPrintf(MPI_COMM_WORLD, "[%i]\n", rank));
152:   for (v = vStart; v < vEnd; v++) {
153:     PetscCall(DMNetworkGetLocalVecOffset(dmclone, v, 0, &off));
154:     PetscCall(DMNetworkGetGlobalVertexIndex(dmclone, v, &vglobal));
155:     switch (cdim) {
156:     case 2:
157:       PetscCall(PetscSynchronizedPrintf(MPI_COMM_WORLD, "Vertex: %" PetscInt_FMT ", x =  %f y = %f \n", vglobal, (double)PetscRealPart(carray[off]), (double)PetscRealPart(carray[off + 1])));
158:       break;
159:     default:
160:       PetscCheck(cdim == 2, MPI_COMM_WORLD, PETSC_ERR_SUP, "Only supports Network embedding dimension of 2, not supplied  %" PetscInt_FMT, cdim);
161:       break;
162:     }
163:   }
164:   PetscCall(PetscSynchronizedFlush(MPI_COMM_WORLD, NULL));
165:   PetscCall(VecRestoreArrayRead(coords, &carray));
166:   PetscFunctionReturn(PETSC_SUCCESS);
167: }

169: int main(int argc, char **argv)
170: {
171:   DM          dm;
172:   PetscInt    dofv = 1, dofe = 1, ne = 1;
173:   PetscMPIInt rank;
174:   PetscBool   testdistribute = PETSC_FALSE;

176:   PetscFunctionBeginUser;
177:   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
178:   PetscCallMPI(MPI_Comm_rank(MPI_COMM_WORLD, &rank));

180:   /* create a distributed k-Star graph DMNetwork */
181:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-dofv", &dofv, NULL));
182:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-dofe", &dofe, NULL));
183:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-ne", &ne, NULL));
184:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-testdistribute", &testdistribute, NULL));
185:   PetscCall(StarGraphCreate(PETSC_COMM_WORLD, dofv, dofe, ne, PETSC_TRUE, &dm));

187:   /* setup a quick R^2 embedding of the star graph */
188:   PetscCall(StarGraphSetCoordinates(dm));

190:   if (testdistribute) {
191:     PetscCall(DMNetworkDistribute(&dm, 0));
192:     PetscCall(DMView(dm, PETSC_VIEWER_STDOUT_WORLD));
193:   }

195:   /* print or view the coordinates of each vertex */
196:   PetscCall(CoordinatePrint(dm));

198:   PetscCall(DMDestroy(&dm));
199:   PetscCall(PetscFinalize());
200: }

202: /*TEST

204:   test:
205:     suffix: 0
206:     args: -ne 4 -testdistribute

208:   test:
209:     suffix: 1
210:     nsize: 2
211:     args: -ne 4 -testdistribute -petscpartitioner_type simple

213:  TEST*/