Actual source code: ex79f.F
petsc-3.4.2 2013-07-02

      1: !
      2: !   This program demonstrates use of MatGetRowIJ() from Fortran
      3: !
      4:       program main
      5:       implicit none
      6: #include <finclude/petscsys.h>
      7: #include <finclude/petscmat.h>
      8: #include <finclude/petscis.h>
      9: #include <finclude/petscviewer.h>

     11:       Mat         A,Ad,Ao
     12:       PetscErrorCode ierr
     13:       PetscMPIInt rank
     14:       PetscViewer v
     15:       PetscInt i,j,ia(1),ja(1)
     16:       PetscInt n,icol(1),rstart
     17:       PetscInt zero,one,rend
     18:       PetscBool   done
     19:       PetscOffset iia,jja,aaa,iicol
     20:       PetscScalar aa(1)

     22:       call PetscInitialize(PETSC_NULL_CHARACTER,ierr)
     23:       call MPI_Comm_rank(PETSC_COMM_WORLD,rank,ierr)

     25:       call PetscViewerBinaryOpen(PETSC_COMM_WORLD,                          &
     26:      & '../../../../share/petsc/datafiles/matrices/' //                       &
     27:      & 'ns-real-int32-float64',                                               &
     28:      &                          FILE_MODE_READ,v,ierr)
     29:       call MatCreate(PETSC_COMM_WORLD,A,ierr)
     30:       call MatSetType(A, MATMPIAIJ,ierr)
     31:       call MatLoad(A,v,ierr)
     32:       CHKERRQ(ierr)
     33:       call MatView(A,PETSC_VIEWER_STDOUT_WORLD,ierr)

     35:       call MatMPIAIJGetSeqAIJ(A,Ad,Ao,icol,iicol,ierr)
     36:       call MatGetOwnershipRange(A,rstart,rend,ierr)
     37: !
     38: !   Print diagonal portion of matrix
     39: !
     40:       call PetscSequentialPhaseBegin(PETSC_COMM_WORLD,1,ierr)
     41:       zero = 0
     42:       one  = 1
     43:       call MatGetRowIJ(Ad,one,zero,zero,n,ia,iia,ja,jja,done,ierr)
     44:       call MatSeqAIJGetArray(Ad,aa,aaa,ierr)
     45:       do 10, i=1,n
     46:         write(7+rank,*) 'row ',i+rstart,' number nonzeros ',                &
     47:      &                   ia(iia+i+1)-ia(iia+i)
     48:         do 20, j=ia(iia+i),ia(iia+i+1)-1
     49:           write(7+rank,*)'  ',j,ja(jja+j)+rstart,aa(aaa+j)
     50:  20     continue
     51:  10   continue
     52:       call MatRestoreRowIJ(Ad,one,zero,zero,n,ia,iia,ja,jja,done,ierr)
     53:       call MatSeqAIJRestoreArray(Ad,aa,aaa,ierr)
     54: !
     55: !   Print off-diagonal portion of matrix
     56: !
     57:       call MatGetRowIJ(Ao,one,zero,zero,n,ia,iia,ja,jja,done,ierr)
     58:       call MatSeqAIJGetArray(Ao,aa,aaa,ierr)
     59:       do 30, i=1,n
     60:         write(7+rank,*) 'row ',i+rstart,' number nonzeros ',               &
     61:      &                  ia(iia+i+1)-ia(iia+i)
     62:         do 40, j=ia(iia+i),ia(iia+i+1)-1
     63:           write(7+rank,*)'  ',j,icol(iicol+ja(jja+j))+1,aa(aaa+j)
     64:  40     continue
     65:  30   continue
     66:       call MatRestoreRowIJ(Ao,one,zero,zero,n,ia,iia,ja,jja,done,ierr)
     67:       call MatSeqAIJRestoreArray(Ao,aa,aaa,ierr)

     69:       call PetscSequentialPhaseEnd(PETSC_COMM_WORLD,1,ierr)

     71:       call MatView(A,PETSC_VIEWER_STDOUT_WORLD,ierr)
     72:       call MatDestroy(A,ierr)
     73:       call PetscViewerDestroy(v,ierr)
     74:       call PetscFinalize(ierr)
     75:       end