1program main 2#include <petsc/finclude/petscvec.h> 3#include <petsc/finclude/petscmat.h> 4 5use petscvec 6use petscmat 7 8implicit none 9 10 Mat A 11 MatPartitioning part 12 IS is 13 PetscInt :: i,m,N 14 PetscInt :: rstart,rend 15 PetscInt,pointer,dimension(:) :: emptyranks,bigranks,cols 16 PetscScalar,pointer,dimension(:) :: vals 17 PetscInt :: & 18 nbigranks = 10, & 19 nemptyranks = 10 20 PetscMPIInt :: rank,sizef 21 PetscErrorCode ierr 22 PetscBool set 23 PetscInt,parameter :: zero = 0, one = 1, two = 2, three = 3 24 25 PetscCallA(PetscInitialize(ierr)) 26 27 PetscCallMPIA(MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)) 28 PetscCallMPIA(MPI_Comm_size(PETSC_COMM_WORLD,sizef,ierr)) 29 30 allocate(emptyranks(nemptyranks)) 31 allocate(bigranks(nbigranks)) 32 33 PetscCallA(PetscOptionsGetIntArray(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-emptyranks',emptyranks,nemptyranks,set,ierr)) 34 PetscCallA(PetscOptionsGetIntArray(PETSC_NULL_OPTIONS,PETSC_NULL_CHARACTER,'-bigranks',bigranks,nbigranks,set,ierr)) 35 36 m = 1 37 do i=1,nemptyranks 38 if (rank == emptyranks(i)) m = 0 39 end do 40 do i=1,nbigranks 41 if (rank == bigranks(i)) m = 5 42 end do 43 44 deallocate(emptyranks) 45 deallocate(bigranks) 46 47 PetscCallA(MatCreate(PETSC_COMM_WORLD,A,ierr)) 48 PetscCallA(MatSetsizes(A,m,m,PETSC_DECIDE,PETSC_DECIDE,ierr)) 49 PetscCallA(MatSetFromOptions(A,ierr)) 50 PetscCallA(MatSeqAIJSetPreallocation(A,three,PETSC_NULL_INTEGER,ierr)) 51 PetscCallA(MatMPIAIJSetPreallocation(A,three,PETSC_NULL_INTEGER,two,PETSC_NULL_INTEGER,ierr)) 52 PetscCallA(MatSeqBAIJSetPreallocation(A,one,three,PETSC_NULL_INTEGER,ierr)) 53 PetscCallA(MatMPIBAIJSetPreallocation(A,one,three,PETSC_NULL_INTEGER,2,PETSC_NULL_INTEGER,ierr)) 54 PetscCallA(MatSeqSBAIJSetPreallocation(A,one,two,PETSC_NULL_INTEGER,ierr)) 55 PetscCallA(MatMPISBAIJSetPreallocation(A,one,two,PETSC_NULL_INTEGER,1,PETSC_NULL_INTEGER,ierr)) 56 57 PetscCallA(MatGetSize(A,PETSC_NULL_INTEGER,N,ierr)) 58 PetscCallA(MatGetOwnershipRange(A,rstart,rend,ierr)) 59 60 allocate(cols(0:3)) 61 allocate(vals(0:3)) 62 do i=rstart,rend-1 63 64 cols = (/mod((i+N-1),N),i,mod((i+1),N)/) 65 vals = [1.0,1.0,1.0] 66 PetscCallA(MatSetValues(A,one,i,three,cols,vals,INSERT_VALUES,ierr)) 67 end do 68 deallocate(cols) 69 deallocate(vals) 70 PetscCallA(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY,ierr)) 71 PetscCallA(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY,ierr)) 72 PetscCallA(MatView(A,PETSC_VIEWER_STDOUT_WORLD,ierr)) 73 74 PetscCallA(MatPartitioningCreate(PETSC_COMM_WORLD,part,ierr)) 75 PetscCallA(MatPartitioningSetAdjacency(part,A,ierr)) 76 PetscCallA(MatPartitioningSetFromOptions(part,ierr)) 77 PetscCallA(MatPartitioningApply(part,is,ierr)) 78 PetscCallA(ISView(is,PETSC_VIEWER_STDOUT_WORLD,ierr)) 79 PetscCallA(ISDestroy(is,ierr)) 80 PetscCallA(MatPartitioningDestroy(part,ierr)) 81 PetscCallA(MatDestroy(A,ierr)) 82 PetscCallA(PetscFinalize(ierr)) 83 84end program 85 86!/*TEST 87! 88! test: 89! nsize: 8 90! args: -emptyranks 0,2,4 -bigranks 1,3,7 -mat_partitioning_type average 91! output_file: output/ex17_1.out 92! # cannot test with external package partitioners since they produce different results on different systems 93! 94!TEST*/ 95