1*c4762a1bSJed Brown static char help[] = "Example of using graph partitioning with a matrix in which some procs have empty ownership\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 i,m,N,rstart,rend,nemptyranks,*emptyranks,nbigranks,*bigranks; 17*c4762a1bSJed Brown PetscMPIInt rank,size; 18*c4762a1bSJed Brown PetscErrorCode ierr; 19*c4762a1bSJed Brown 20*c4762a1bSJed Brown ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 21*c4762a1bSJed Brown ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr); 22*c4762a1bSJed Brown ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr); 23*c4762a1bSJed Brown 24*c4762a1bSJed Brown nemptyranks = 10; 25*c4762a1bSJed Brown nbigranks = 10; 26*c4762a1bSJed Brown ierr = PetscMalloc2(nemptyranks,&emptyranks,nbigranks,&bigranks);CHKERRQ(ierr); 27*c4762a1bSJed Brown 28*c4762a1bSJed Brown ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Partitioning example options",NULL);CHKERRQ(ierr); 29*c4762a1bSJed Brown ierr = PetscOptionsIntArray("-emptyranks","Ranks to be skipped by partition","",emptyranks,&nemptyranks,NULL);CHKERRQ(ierr); 30*c4762a1bSJed Brown ierr = PetscOptionsIntArray("-bigranks","Ranks to be overloaded","",bigranks,&nbigranks,NULL);CHKERRQ(ierr); 31*c4762a1bSJed Brown ierr = PetscOptionsEnd();CHKERRQ(ierr); 32*c4762a1bSJed Brown 33*c4762a1bSJed Brown m = 1; 34*c4762a1bSJed Brown for (i=0; i<nemptyranks; i++) if (rank == emptyranks[i]) m = 0; 35*c4762a1bSJed Brown for (i=0; i<nbigranks; i++) if (rank == bigranks[i]) m = 5; 36*c4762a1bSJed Brown 37*c4762a1bSJed Brown ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr); 38*c4762a1bSJed Brown ierr = MatSetSizes(A,m,m,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr); 39*c4762a1bSJed Brown ierr = MatSetFromOptions(A);CHKERRQ(ierr); 40*c4762a1bSJed Brown ierr = MatSeqAIJSetPreallocation(A,3,NULL);CHKERRQ(ierr); 41*c4762a1bSJed Brown ierr = MatMPIAIJSetPreallocation(A,3,NULL,2,NULL);CHKERRQ(ierr); 42*c4762a1bSJed Brown ierr = MatSeqBAIJSetPreallocation(A,1,3,NULL);CHKERRQ(ierr); 43*c4762a1bSJed Brown ierr = MatMPIBAIJSetPreallocation(A,1,3,NULL,2,NULL);CHKERRQ(ierr); 44*c4762a1bSJed Brown ierr = MatSeqSBAIJSetPreallocation(A,1,2,NULL);CHKERRQ(ierr); 45*c4762a1bSJed Brown ierr = MatMPISBAIJSetPreallocation(A,1,2,NULL,1,NULL);CHKERRQ(ierr); 46*c4762a1bSJed Brown 47*c4762a1bSJed Brown ierr = MatGetSize(A,NULL,&N);CHKERRQ(ierr); 48*c4762a1bSJed Brown ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr); 49*c4762a1bSJed Brown for (i=rstart; i<rend; i++) { 50*c4762a1bSJed Brown const PetscInt cols[] = {(i+N-1)%N,i,(i+1)%N}; 51*c4762a1bSJed Brown const PetscScalar vals[] = {1,1,1}; 52*c4762a1bSJed Brown ierr = MatSetValues(A,1,&i,3,cols,vals,INSERT_VALUES);CHKERRQ(ierr); 53*c4762a1bSJed Brown } 54*c4762a1bSJed Brown ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 55*c4762a1bSJed Brown ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 56*c4762a1bSJed Brown ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 57*c4762a1bSJed Brown 58*c4762a1bSJed Brown ierr = MatPartitioningCreate(PETSC_COMM_WORLD,&part);CHKERRQ(ierr); 59*c4762a1bSJed Brown ierr = MatPartitioningSetAdjacency(part,A);CHKERRQ(ierr); 60*c4762a1bSJed Brown ierr = MatPartitioningSetFromOptions(part);CHKERRQ(ierr); 61*c4762a1bSJed Brown ierr = MatPartitioningApply(part,&is);CHKERRQ(ierr); 62*c4762a1bSJed Brown ierr = ISView(is,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 63*c4762a1bSJed Brown ierr = ISDestroy(&is);CHKERRQ(ierr); 64*c4762a1bSJed Brown ierr = MatPartitioningDestroy(&part);CHKERRQ(ierr); 65*c4762a1bSJed Brown ierr = MatDestroy(&A);CHKERRQ(ierr); 66*c4762a1bSJed Brown ierr = PetscFree2(emptyranks,bigranks);CHKERRQ(ierr); 67*c4762a1bSJed Brown ierr = PetscFinalize(); 68*c4762a1bSJed Brown return ierr; 69*c4762a1bSJed Brown } 70*c4762a1bSJed Brown 71*c4762a1bSJed Brown /*TEST 72*c4762a1bSJed Brown 73*c4762a1bSJed Brown build: 74*c4762a1bSJed Brown requires: c99 75*c4762a1bSJed Brown 76*c4762a1bSJed Brown test: 77*c4762a1bSJed Brown nsize: 8 78*c4762a1bSJed Brown args: -emptyranks 0,2,4 -bigranks 1,3,7 -mat_partitioning_type average 79*c4762a1bSJed Brown # cannot test with external package partitioners since they produce different results on different systems 80*c4762a1bSJed Brown 81*c4762a1bSJed Brown TEST*/ 82