1*c4762a1bSJed Brown static char help[] = "Example of using graph partitioning to partition a graph\n\n"; 2*c4762a1bSJed Brown 3*c4762a1bSJed Brown /*T 4*c4762a1bSJed Brown Concepts: Mat^mat partitioning 5*c4762a1bSJed Brown Concepts: Mat^image segmentation 6*c4762a1bSJed Brown Processors: n 7*c4762a1bSJed Brown T*/ 8*c4762a1bSJed Brown 9*c4762a1bSJed Brown #include <petscmat.h> 10*c4762a1bSJed Brown 11*c4762a1bSJed Brown int main(int argc, char **args) 12*c4762a1bSJed Brown { 13*c4762a1bSJed Brown Mat A; 14*c4762a1bSJed Brown MatPartitioning part; 15*c4762a1bSJed Brown IS is; 16*c4762a1bSJed Brown PetscInt r,N = 10, start, end, *vweights; 17*c4762a1bSJed Brown PetscBool set_vweights=PETSC_FALSE,use_edge_weights=PETSC_FALSE; 18*c4762a1bSJed Brown PetscMPIInt rank; 19*c4762a1bSJed Brown MPI_Comm comm; 20*c4762a1bSJed Brown PetscErrorCode ierr; 21*c4762a1bSJed Brown 22*c4762a1bSJed Brown ierr = PetscInitialize(&argc, &args, (char*) 0, help);if (ierr) return ierr; 23*c4762a1bSJed Brown comm = PETSC_COMM_WORLD; 24*c4762a1bSJed Brown ierr = PetscOptionsGetInt(NULL,NULL, "-N", &N, NULL);CHKERRQ(ierr); 25*c4762a1bSJed Brown ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr); 26*c4762a1bSJed Brown ierr = MatCreate(comm, &A);CHKERRQ(ierr); 27*c4762a1bSJed Brown ierr = MatSetSizes(A, PETSC_DECIDE, PETSC_DECIDE, N, N);CHKERRQ(ierr); 28*c4762a1bSJed Brown ierr = MatSetFromOptions(A);CHKERRQ(ierr); 29*c4762a1bSJed Brown ierr = MatSeqAIJSetPreallocation(A, 3, NULL);CHKERRQ(ierr); 30*c4762a1bSJed Brown ierr = MatMPIAIJSetPreallocation(A, 3, NULL, 2, NULL);CHKERRQ(ierr); 31*c4762a1bSJed Brown ierr = PetscOptionsGetBool(NULL,NULL,"-test_vertex_weights",&set_vweights,NULL);CHKERRQ(ierr); 32*c4762a1bSJed Brown ierr = PetscOptionsGetBool(NULL,NULL,"-test_use_edge_weights",&use_edge_weights,NULL);CHKERRQ(ierr); 33*c4762a1bSJed Brown /* Create a linear mesh */ 34*c4762a1bSJed Brown ierr = MatGetOwnershipRange(A, &start, &end);CHKERRQ(ierr); 35*c4762a1bSJed Brown if (set_vweights) { 36*c4762a1bSJed Brown ierr = PetscMalloc1(end-start,&vweights);CHKERRQ(ierr); 37*c4762a1bSJed Brown for (r = start; r < end; ++r) 38*c4762a1bSJed Brown vweights[r-start] = rank+1; 39*c4762a1bSJed Brown } 40*c4762a1bSJed Brown for (r = start; r < end; ++r) { 41*c4762a1bSJed Brown if (r == 0) { 42*c4762a1bSJed Brown PetscInt cols[2]; 43*c4762a1bSJed Brown PetscScalar vals[2]; 44*c4762a1bSJed Brown 45*c4762a1bSJed Brown cols[0] = r; cols[1] = r+1; 46*c4762a1bSJed Brown vals[0] = 1.0; vals[1] = use_edge_weights? 2.0: 1.0; 47*c4762a1bSJed Brown 48*c4762a1bSJed Brown ierr = MatSetValues(A, 1, &r, 2, cols, vals, INSERT_VALUES);CHKERRQ(ierr); 49*c4762a1bSJed Brown } else if (r == N-1) { 50*c4762a1bSJed Brown PetscInt cols[2]; 51*c4762a1bSJed Brown PetscScalar vals[2]; 52*c4762a1bSJed Brown 53*c4762a1bSJed Brown cols[0] = r-1; cols[1] = r; 54*c4762a1bSJed Brown vals[0] = use_edge_weights? 3.0:1.0; vals[1] = 1.0; 55*c4762a1bSJed Brown 56*c4762a1bSJed Brown ierr = MatSetValues(A, 1, &r, 2, cols, vals, INSERT_VALUES);CHKERRQ(ierr); 57*c4762a1bSJed Brown } else { 58*c4762a1bSJed Brown PetscInt cols[3]; 59*c4762a1bSJed Brown PetscScalar vals[3]; 60*c4762a1bSJed Brown 61*c4762a1bSJed Brown cols[0] = r-1; cols[1] = r; cols[2] = r+1; 62*c4762a1bSJed Brown /* ADJ matrix needs to be symmetric */ 63*c4762a1bSJed Brown vals[0] = use_edge_weights? (cols[0]==0? 2.0:5.0):1.0; 64*c4762a1bSJed Brown vals[1] = 1.0; 65*c4762a1bSJed Brown vals[2] = use_edge_weights? (cols[2]==N-1? 3.0:5.0):1.0; 66*c4762a1bSJed Brown 67*c4762a1bSJed Brown ierr = MatSetValues(A, 1, &r, 3, cols, vals, INSERT_VALUES);CHKERRQ(ierr); 68*c4762a1bSJed Brown } 69*c4762a1bSJed Brown } 70*c4762a1bSJed Brown ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 71*c4762a1bSJed Brown ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 72*c4762a1bSJed Brown 73*c4762a1bSJed Brown ierr = MatPartitioningCreate(comm, &part);CHKERRQ(ierr); 74*c4762a1bSJed Brown ierr = MatPartitioningSetAdjacency(part, A);CHKERRQ(ierr); 75*c4762a1bSJed Brown if (set_vweights) { 76*c4762a1bSJed Brown ierr = MatPartitioningSetVertexWeights(part,vweights);CHKERRQ(ierr); 77*c4762a1bSJed Brown } 78*c4762a1bSJed Brown if (use_edge_weights) { 79*c4762a1bSJed Brown ierr = MatPartitioningSetUseEdgeWeights(part,use_edge_weights);CHKERRQ(ierr); 80*c4762a1bSJed Brown 81*c4762a1bSJed Brown ierr = MatPartitioningGetUseEdgeWeights(part,&use_edge_weights);CHKERRQ(ierr); 82*c4762a1bSJed Brown if (!use_edge_weights) SETERRQ(comm,PETSC_ERR_ARG_INCOMP, "use_edge_weights flag does not setup correctly \n"); 83*c4762a1bSJed Brown } 84*c4762a1bSJed Brown ierr = MatPartitioningSetFromOptions(part);CHKERRQ(ierr); 85*c4762a1bSJed Brown ierr = MatPartitioningApply(part, &is);CHKERRQ(ierr); 86*c4762a1bSJed Brown ierr = ISView(is, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 87*c4762a1bSJed Brown ierr = ISDestroy(&is);CHKERRQ(ierr); 88*c4762a1bSJed Brown ierr = MatPartitioningDestroy(&part);CHKERRQ(ierr); 89*c4762a1bSJed Brown 90*c4762a1bSJed Brown ierr = MatDestroy(&A);CHKERRQ(ierr); 91*c4762a1bSJed Brown ierr = PetscFinalize(); 92*c4762a1bSJed Brown return ierr; 93*c4762a1bSJed Brown } 94*c4762a1bSJed Brown 95*c4762a1bSJed Brown 96*c4762a1bSJed Brown /*TEST 97*c4762a1bSJed Brown 98*c4762a1bSJed Brown test: 99*c4762a1bSJed Brown nsize: 3 100*c4762a1bSJed Brown requires: parmetis 101*c4762a1bSJed Brown args: -mat_partitioning_type parmetis 102*c4762a1bSJed Brown 103*c4762a1bSJed Brown test: 104*c4762a1bSJed Brown suffix: 2 105*c4762a1bSJed Brown nsize: 3 106*c4762a1bSJed Brown requires: ptscotch 107*c4762a1bSJed Brown args: -mat_partitioning_type ptscotch 108*c4762a1bSJed Brown 109*c4762a1bSJed Brown test: 110*c4762a1bSJed Brown suffix: 3 111*c4762a1bSJed Brown nsize: 4 112*c4762a1bSJed Brown requires: party 113*c4762a1bSJed Brown args: -mat_partitioning_type party 114*c4762a1bSJed Brown 115*c4762a1bSJed Brown test: 116*c4762a1bSJed Brown suffix: 4 117*c4762a1bSJed Brown nsize: 3 118*c4762a1bSJed Brown requires: chaco 119*c4762a1bSJed Brown args: -mat_partitioning_type chaco 120*c4762a1bSJed Brown 121*c4762a1bSJed Brown test: 122*c4762a1bSJed Brown suffix: 5 123*c4762a1bSJed Brown nsize: 3 124*c4762a1bSJed Brown requires: parmetis 125*c4762a1bSJed Brown args: -mat_partitioning_type hierarch -mat_partitioning_hierarchical_nfineparts 3 -mat_partitioning_nparts 10 -N 100 126*c4762a1bSJed Brown 127*c4762a1bSJed Brown test: 128*c4762a1bSJed Brown suffix: 6 129*c4762a1bSJed Brown nsize: 3 130*c4762a1bSJed Brown requires: parmetis 131*c4762a1bSJed Brown args: -mat_partitioning_type hierarch -mat_partitioning_hierarchical_nfineparts 3 -mat_partitioning_nparts 10 -N 100 -test_vertex_weights 1 -mat_partitioning_use_edge_weights 1 132*c4762a1bSJed Brown 133*c4762a1bSJed Brown test: 134*c4762a1bSJed Brown suffix: 7 135*c4762a1bSJed Brown nsize: 2 136*c4762a1bSJed Brown requires: parmetis 137*c4762a1bSJed Brown args: -mat_partitioning_type hierarch -mat_partitioning_hierarchical_nfineparts 2 -mat_partitioning_nparts 10 -mat_partitioning_hierarchical_fineparttype hierarch -malloc_dump -N 100 -mat_partitioning_improve 1 138*c4762a1bSJed Brown 139*c4762a1bSJed Brown test: 140*c4762a1bSJed Brown suffix: 8 141*c4762a1bSJed Brown nsize: 2 142*c4762a1bSJed Brown requires: parmetis 143*c4762a1bSJed Brown args: -mat_partitioning_type parmetis -mat_partitioning_nparts 3 -test_use_edge_weights 1 144*c4762a1bSJed Brown 145*c4762a1bSJed Brown test: 146*c4762a1bSJed Brown suffix: 9 147*c4762a1bSJed Brown nsize: 2 148*c4762a1bSJed Brown requires: ptscotch 149*c4762a1bSJed Brown args: -mat_partitioning_type ptscotch -mat_partitioning_nparts 3 -test_use_edge_weights 1 -mat_partitioning_ptscotch_proc_weight 0 150*c4762a1bSJed Brown 151*c4762a1bSJed Brown TEST*/ 152