GetDiagonal

This routine returns the diagonal entries of sparse MATRIX.

Interface

📝 Interface 1

INTERFACE
  MODULE SUBROUTINE GetDiagonal(obj, diag, idiag, offset)
    TYPE(CSRMatrix_), INTENT(IN) :: obj
    REAL(DFP), ALLOCATABLE, INTENT(INOUT) :: diag(:)
    INTEGER(I4B), ALLOCATABLE, INTENT(INOUT) :: idiag(:)
    INTEGER(I4B), OPTIONAL, INTENT(IN) :: offset
  END SUBROUTINE GetDiagonal
END INTERFACE

• This subroutine returns the diagonal entries of sparse matrix.
• offset containing the offset of the wanted diagonal the diagonal extracted is the one corresponding to the entries a(i,j) with j-i = ioff. Thus ioff = 0 means the main diagonal
• diag is an array of reals of length nrow containing the wanted diagonal. diag contains the diagonal (a(i,j),j-i = ioff) as defined above.
• idiag is an array of integer of length len, containing the poisitions in the original arrays a and ja of the diagonal elements collected in diag. A zero entry in idiag(i) means that there was no entry found in row i belonging to the diagonal.

Interface 2

INTERFACE
  MODULE SUBROUTINE GetDiagonal(obj, diag, offset)
    TYPE(CSRMatrix_), INTENT(INOUT) :: obj
    REAL(DFP), ALLOCATABLE, INTENT(INOUT) :: diag(:)
    INTEGER(I4B), OPTIONAL, INTENT(IN) :: offset
  END SUBROUTINE GetDiagonal
END INTERFACE

This routine is like interface-1, but in this routine we do not get idiag

◉ Close