1c4762a1bSJed Brown#include <petsc/finclude/petscmat.h> 2*c5e229c2SMartin Diehlprogram main 3c4762a1bSJed Brown use petscmat 4c4762a1bSJed Brown 5c4762a1bSJed Brown implicit none 6c4762a1bSJed Brown 7c4762a1bSJed Brown Mat A 8c4762a1bSJed Brown PetscInt, parameter :: n = 5, m = 5 9c4762a1bSJed Brown PetscScalar, parameter :: two = 2.0, one = 1.0 10c4762a1bSJed Brown PetscInt, pointer, dimension(:) :: dnnz, onnz 11c4762a1bSJed Brown PetscInt :: i, rstart, rend, M1, N1 12c4762a1bSJed Brown PetscErrorCode ierr 13c4762a1bSJed Brown 14d8606c27SBarry Smith PetscCallA(PetscInitialize(ierr)) 15c4762a1bSJed Brown 16c4762a1bSJed Brown allocate (dnnz(0:m - 1)) 17c4762a1bSJed Brown allocate (onnz(0:m - 1)) 18c4762a1bSJed Brown 19c4762a1bSJed Brown do i = 0, m - 1 20c4762a1bSJed Brown dnnz(i) = 1 21c4762a1bSJed Brown onnz(i) = 1 22c4762a1bSJed Brown end do 23c4762a1bSJed Brown 24d8606c27SBarry Smith PetscCallA(MatCreateAIJ(PETSC_COMM_WORLD, m, n, PETSC_DETERMINE, PETSC_DETERMINE, PETSC_DECIDE, dnnz, PETSC_DECIDE, onnz, A, ierr)) 25d8606c27SBarry Smith PetscCallA(MatSetFromOptions(A, ierr)) 26d8606c27SBarry Smith PetscCallA(MatSetUp(A, ierr)) 27c4762a1bSJed Brown deallocate (dnnz) 28c4762a1bSJed Brown deallocate (onnz) 29c4762a1bSJed Brown 30c4762a1bSJed Brown !/* This assembly shrinks memory because we do not insert enough number of values */ 31d8606c27SBarry Smith PetscCallA(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY, ierr)) 32d8606c27SBarry Smith PetscCallA(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY, ierr)) 33c4762a1bSJed Brown 34c4762a1bSJed Brown !/* MatResetPreallocation restores the memory required by users */ 35d8606c27SBarry Smith PetscCallA(MatResetPreallocation(A, ierr)) 36d8606c27SBarry Smith PetscCallA(MatSetOption(A, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_TRUE, ierr)) 37d8606c27SBarry Smith PetscCallA(MatGetOwnershipRange(A, rstart, rend, ierr)) 38d8606c27SBarry Smith PetscCallA(MatGetSize(A, M1, N1, ierr)) 39c4762a1bSJed Brown do i = rstart, rend - 1 40d8606c27SBarry Smith PetscCallA(MatSetValue(A, i, i, two, INSERT_VALUES, ierr)) 41d8606c27SBarry Smith if (rend < N1) PetscCallA(MatSetValue(A, i, rend, one, INSERT_VALUES, ierr)) 42c4762a1bSJed Brown end do 43d8606c27SBarry Smith PetscCallA(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY, ierr)) 44d8606c27SBarry Smith PetscCallA(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY, ierr)) 45d8606c27SBarry Smith PetscCallA(MatView(A, PETSC_VIEWER_STDOUT_WORLD, ierr)) 46d8606c27SBarry Smith PetscCallA(MatDestroy(A, ierr)) 47d8606c27SBarry Smith PetscCallA(PetscFinalize(ierr)) 48c4762a1bSJed Brown 49c4762a1bSJed Brownend program 50c4762a1bSJed Brown 51c4762a1bSJed Brown!/*TEST 52c4762a1bSJed Brown! 53c4762a1bSJed Brown! test: 54c4762a1bSJed Brown! suffix: 1 55c4762a1bSJed Brown! output_file: output/ex4_1.out 56c4762a1bSJed Brown! 57c4762a1bSJed Brown! test: 58c4762a1bSJed Brown! suffix: 2 59c4762a1bSJed Brown! nsize: 2 60c4762a1bSJed Brown! output_file: output/ex4_2.out 61c4762a1bSJed Brown! 62c4762a1bSJed Brown!TEST*/ 63