1c4762a1bSJed Brown 2c4762a1bSJed Brown static char help[] = "Partition a tiny grid using hierarchical partitioning.\n\n"; 3c4762a1bSJed Brown 4c4762a1bSJed Brown /*T 5c4762a1bSJed Brown Concepts: partitioning 6c4762a1bSJed Brown Processors: 4 7c4762a1bSJed Brown T*/ 8c4762a1bSJed Brown 9c4762a1bSJed Brown /* 10c4762a1bSJed Brown Include "petscmat.h" so that we can use matrices. Note that this file 11c4762a1bSJed Brown automatically includes: 12c4762a1bSJed Brown petscsys.h - base PETSc routines petscvec.h - vectors 13c4762a1bSJed Brown petscmat.h - matrices 14c4762a1bSJed Brown petscis.h - index sets 15c4762a1bSJed Brown petscviewer.h - viewers 16c4762a1bSJed Brown */ 17c4762a1bSJed Brown #include <petscmat.h> 18c4762a1bSJed Brown 19c4762a1bSJed Brown int main(int argc,char **args) 20c4762a1bSJed Brown { 21c4762a1bSJed Brown Mat A; 22c4762a1bSJed Brown PetscErrorCode ierr; 23c4762a1bSJed Brown PetscMPIInt rank,size; 24c4762a1bSJed Brown PetscInt *ia,*ja; 25c4762a1bSJed Brown MatPartitioning part; 26c4762a1bSJed Brown IS is,isn,isrows; 27c4762a1bSJed Brown IS coarseparts,fineparts; 28c4762a1bSJed Brown MPI_Comm comm; 29c4762a1bSJed Brown 30c4762a1bSJed Brown ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 31c4762a1bSJed Brown comm = PETSC_COMM_WORLD; 32ffc4695bSBarry Smith ierr = MPI_Comm_size(comm,&size);CHKERRMPI(ierr); 33*2c71b3e2SJacob Faibussowitsch PetscCheckFalse(size != 4,comm,PETSC_ERR_WRONG_MPI_SIZE,"Must run with 4 processors"); 34ffc4695bSBarry Smith ierr = MPI_Comm_rank(comm,&rank);CHKERRMPI(ierr); 35c4762a1bSJed Brown 36c4762a1bSJed Brown ierr = PetscMalloc1(5,&ia);CHKERRQ(ierr); 37c4762a1bSJed Brown ierr = PetscMalloc1(16,&ja);CHKERRQ(ierr); 38dd400576SPatrick Sanan if (rank == 0) { 39c4762a1bSJed Brown ja[0] = 1; ja[1] = 4; ja[2] = 0; ja[3] = 2; ja[4] = 5; ja[5] = 1; ja[6] = 3; ja[7] = 6; 40c4762a1bSJed Brown ja[8] = 2; ja[9] = 7; 41c4762a1bSJed Brown ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10; 42c4762a1bSJed Brown } else if (rank == 1) { 43c4762a1bSJed Brown ja[0] = 0; ja[1] = 5; ja[2] = 8; ja[3] = 1; ja[4] = 4; ja[5] = 6; ja[6] = 9; ja[7] = 2; 44c4762a1bSJed Brown ja[8] = 5; ja[9] = 7; ja[10] = 10; ja[11] = 3; ja[12] = 6; ja[13] = 11; 45c4762a1bSJed Brown ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14; 46c4762a1bSJed Brown } else if (rank == 2) { 47c4762a1bSJed Brown ja[0] = 4; ja[1] = 9; ja[2] = 12; ja[3] = 5; ja[4] = 8; ja[5] = 10; ja[6] = 13; ja[7] = 6; 48c4762a1bSJed Brown ja[8] = 9; ja[9] = 11; ja[10] = 14; ja[11] = 7; ja[12] = 10; ja[13] = 15; 49c4762a1bSJed Brown ia[0] = 0; ia[1] = 3; ia[2] = 7; ia[3] = 11; ia[4] = 14; 50c4762a1bSJed Brown } else { 51c4762a1bSJed Brown ja[0] = 8; ja[1] = 13; ja[2] = 9; ja[3] = 12; ja[4] = 14; ja[5] = 10; ja[6] = 13; ja[7] = 15; 52c4762a1bSJed Brown ja[8] = 11; ja[9] = 14; 53c4762a1bSJed Brown ia[0] = 0; ia[1] = 2; ia[2] = 5; ia[3] = 8; ia[4] = 10; 54c4762a1bSJed Brown } 55c4762a1bSJed Brown ierr = MatCreateMPIAdj(comm,4,16,ia,ja,NULL,&A);CHKERRQ(ierr); 56c4762a1bSJed Brown ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 57c4762a1bSJed Brown /* 58c4762a1bSJed Brown Partition the graph of the matrix 59c4762a1bSJed Brown */ 60c4762a1bSJed Brown ierr = MatPartitioningCreate(comm,&part);CHKERRQ(ierr); 61c4762a1bSJed Brown ierr = MatPartitioningSetAdjacency(part,A);CHKERRQ(ierr); 62c4762a1bSJed Brown ierr = MatPartitioningSetType(part,MATPARTITIONINGHIERARCH);CHKERRQ(ierr); 63c4762a1bSJed Brown ierr = MatPartitioningHierarchicalSetNcoarseparts(part,2);CHKERRQ(ierr); 64c4762a1bSJed Brown ierr = MatPartitioningHierarchicalSetNfineparts(part,2);CHKERRQ(ierr); 65c4762a1bSJed Brown ierr = MatPartitioningSetFromOptions(part);CHKERRQ(ierr); 66c4762a1bSJed Brown /* get new processor owner number of each vertex */ 67c4762a1bSJed Brown ierr = MatPartitioningApply(part,&is);CHKERRQ(ierr); 68c4762a1bSJed Brown /* coarse parts */ 69c4762a1bSJed Brown ierr = MatPartitioningHierarchicalGetCoarseparts(part,&coarseparts);CHKERRQ(ierr); 70c4762a1bSJed Brown ierr = ISView(coarseparts,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 71c4762a1bSJed Brown /* fine parts */ 72c4762a1bSJed Brown ierr = MatPartitioningHierarchicalGetFineparts(part,&fineparts);CHKERRQ(ierr); 73c4762a1bSJed Brown ierr = ISView(fineparts,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 74c4762a1bSJed Brown /* partitioning */ 75c4762a1bSJed Brown ierr = ISView(is,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 76c4762a1bSJed Brown /* get new global number of each old global number */ 77c4762a1bSJed Brown ierr = ISPartitioningToNumbering(is,&isn);CHKERRQ(ierr); 78c4762a1bSJed Brown ierr = ISView(isn,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 79c4762a1bSJed Brown ierr = ISBuildTwoSided(is,NULL,&isrows);CHKERRQ(ierr); 80c4762a1bSJed Brown ierr = ISView(isrows,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); 81c4762a1bSJed Brown ierr = ISDestroy(&is);CHKERRQ(ierr); 82c4762a1bSJed Brown ierr = ISDestroy(&coarseparts);CHKERRQ(ierr); 83c4762a1bSJed Brown ierr = ISDestroy(&fineparts);CHKERRQ(ierr); 84c4762a1bSJed Brown ierr = ISDestroy(&isrows);CHKERRQ(ierr); 85c4762a1bSJed Brown ierr = ISDestroy(&isn);CHKERRQ(ierr); 86c4762a1bSJed Brown ierr = MatPartitioningDestroy(&part);CHKERRQ(ierr); 87c4762a1bSJed Brown /* 88c4762a1bSJed Brown Free work space. All PETSc objects should be destroyed when they 89c4762a1bSJed Brown are no longer needed. 90c4762a1bSJed Brown */ 91c4762a1bSJed Brown ierr = MatDestroy(&A);CHKERRQ(ierr); 92c4762a1bSJed Brown ierr = PetscFinalize(); 93c4762a1bSJed Brown return ierr; 94c4762a1bSJed Brown } 95c4762a1bSJed Brown 96c4762a1bSJed Brown /*TEST 97c4762a1bSJed Brown 98c4762a1bSJed Brown test: 99c4762a1bSJed Brown nsize: 4 100c4762a1bSJed Brown requires: parmetis 101c4762a1bSJed Brown TODO: tests cannot use parmetis because it produces different results on different machines 102c4762a1bSJed Brown 103c4762a1bSJed Brown TEST*/ 104