xref: /petsc/src/mat/tests/ex241f.F90 (revision d33816bfcbbe95b28482189fc4eaa06ffaf4fc8d)
1c4762a1bSJed Brown!     Test code contributed by Thibaut Appel <t.appel17@imperial.ac.uk>
2c4762a1bSJed Brown
3c4762a1bSJed Brown  program test_assembly
4c4762a1bSJed Brown
5c4762a1bSJed Brown#include <petsc/finclude/petscmat.h>
6c4762a1bSJed Brown
7c4762a1bSJed Brown  use PetscMat
8*d33816bfSBarry Smith  use ISO_Fortran_Env, only : real64
9c4762a1bSJed Brown
10c4762a1bSJed Brown  implicit none
11c4762a1bSJed Brown  PetscInt,    parameter :: wp = real64, n = 10
12c4762a1bSJed Brown  PetscScalar, parameter :: zero = 0.0, one = 1.0
13c4762a1bSJed Brown  Mat      :: L
14c4762a1bSJed Brown  PetscInt :: istart, iend, row, i1, i0
15c4762a1bSJed Brown  PetscErrorCode :: ierr
16c4762a1bSJed Brown
17c4762a1bSJed Brown  PetscInt    cols(1),rows(1)
18c4762a1bSJed Brown  PetscScalar  vals(1)
19c4762a1bSJed Brown
20c4762a1bSJed Brown  call PetscInitialize(PETSC_NULL_CHARACTER,ierr)
21c4762a1bSJed Brown  if (ierr .ne. 0) then
22c4762a1bSJed Brown    print*,'Unable to initialize PETSc'
23c4762a1bSJed Brown    stop
24c4762a1bSJed Brown  endif
25c4762a1bSJed Brown
26c4762a1bSJed Brown  i0 = 0
27c4762a1bSJed Brown  i1 = 1
28c4762a1bSJed Brown
29c4762a1bSJed Brown  call MatCreate(PETSC_COMM_WORLD,L,ierr); CHKERRA(ierr)
30c4762a1bSJed Brown  call MatSetType(L,MATAIJ,ierr); CHKERRA(ierr)
31c4762a1bSJed Brown  call MatSetSizes(L,PETSC_DECIDE,PETSC_DECIDE,n,n,ierr); CHKERRA(ierr)
32c4762a1bSJed Brown
33c4762a1bSJed Brown  call MatSeqAIJSetPreallocation(L,i1,PETSC_NULL_INTEGER,ierr); CHKERRA(ierr)
34c4762a1bSJed Brown  call MatMPIAIJSetPreallocation(L,i1,PETSC_NULL_INTEGER,i0,PETSC_NULL_INTEGER,ierr); CHKERRA(ierr) ! No allocated non-zero in off-diagonal part
35c4762a1bSJed Brown  call MatSetOption(L,MAT_IGNORE_ZERO_ENTRIES,PETSC_TRUE,ierr); CHKERRA(ierr)
36c4762a1bSJed Brown  call MatSetOption(L,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE,ierr); CHKERRA(ierr)
37c4762a1bSJed Brown  call MatSetOption(L,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE,ierr); CHKERRA(ierr)
38c4762a1bSJed Brown
39c4762a1bSJed Brown  call MatGetOwnershipRange(L,istart,iend,ierr); CHKERRA(ierr)
40c4762a1bSJed Brown
41c4762a1bSJed Brown  ! assembling a diagonal matrix
42c4762a1bSJed Brown  do row = istart,iend-1
43c4762a1bSJed Brown
44c4762a1bSJed Brown    cols = [row]; vals = [one]; rows = [row];
45c4762a1bSJed Brown    call MatSetValues(L,i1,rows,i1,cols,vals,ADD_VALUES,ierr); CHKERRA(ierr)
46c4762a1bSJed Brown
47c4762a1bSJed Brown  end do
48c4762a1bSJed Brown
49c4762a1bSJed Brown  call MatAssemblyBegin(L,MAT_FINAL_ASSEMBLY,ierr); CHKERRA(ierr)
50c4762a1bSJed Brown  call MatAssemblyEnd(L,MAT_FINAL_ASSEMBLY,ierr); CHKERRA(ierr)
51c4762a1bSJed Brown
52c4762a1bSJed Brown  call MatSetOption(L,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE,ierr); CHKERRA(ierr)
53c4762a1bSJed Brown
54c4762a1bSJed Brown  !call MatZeroEntries(L,ierr); CHKERRA(ierr)
55c4762a1bSJed Brown
56c4762a1bSJed Brown  ! assembling a diagonal matrix, adding a zero value to non-diagonal part
57c4762a1bSJed Brown  do row = istart,iend-1
58c4762a1bSJed Brown
59c4762a1bSJed Brown    if (row == 0) then
60c4762a1bSJed Brown      cols = [n-1]
61c4762a1bSJed Brown      vals = [zero]
62c4762a1bSJed Brown      rows = [row]
63c4762a1bSJed Brown      call MatSetValues(L,i1,rows,i1,cols,vals,ADD_VALUES,ierr); CHKERRA(ierr)
64c4762a1bSJed Brown    end if
65c4762a1bSJed Brown    cols = [row]; vals = [one] ; rows = [ row];
66c4762a1bSJed Brown    call MatSetValues(L,i1,rows,i1,cols,vals,ADD_VALUES,ierr); CHKERRA(ierr)
67c4762a1bSJed Brown
68c4762a1bSJed Brown  end do
69c4762a1bSJed Brown
70c4762a1bSJed Brown  call MatAssemblyBegin(L,MAT_FINAL_ASSEMBLY,ierr); CHKERRA(ierr)
71c4762a1bSJed Brown  call MatAssemblyEnd(L,MAT_FINAL_ASSEMBLY,ierr); CHKERRA(ierr)
72c4762a1bSJed Brown  call MatDestroy(L,ierr); CHKERRA(ierr)
73c4762a1bSJed Brown
74c4762a1bSJed Brown  call PetscFinalize(ierr)
75c4762a1bSJed Brown
76c4762a1bSJed Brownend program test_assembly
77c4762a1bSJed Brown
78c4762a1bSJed Brown!/*TEST
79c4762a1bSJed Brown!
80c4762a1bSJed Brown!   build:
81c4762a1bSJed Brown!      requires: complex
82c4762a1bSJed Brown!
83c4762a1bSJed Brown!   test:
84c4762a1bSJed Brown!      nsize: 2
85c4762a1bSJed Brown!
86c4762a1bSJed Brown!TEST*/
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