!>
!> DLATRF_AA factorizes a panel of a real symmetric matrix A using
!> the Aasen's algorithm. The panel consists of a set of NB rows of A
!> when UPLO is U, or a set of NB columns when UPLO is L.
!>
!> In order to factorize the panel, the Aasen's algorithm requires the
!> last row, or column, of the previous panel. The first row, or column,
!> of A is set to be the first row, or column, of an identity matrix,
!> which is used to factorize the first panel.
!>
!> The resulting J-th row of U, or J-th column of L, is stored in the
!> (J-1)-th row, or column, of A (without the unit diagonals), while
!> the diagonal and subdiagonal of A are overwritten by those of T.
!>
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          = 'U':  Upper triangle of A is stored;
!>          = 'L':  Lower triangle of A is stored.
!> 

J1

!>          J1 is INTEGER
!>          The location of the first row, or column, of the panel
!>          within the submatrix of A, passed to this routine, e.g.,
!>          when called by DSYTRF_AA, for the first panel, J1 is 1,
!>          while for the remaining panels, J1 is 2.
!> 

M

!>          M is INTEGER
!>          The dimension of the submatrix. M >= 0.
!> 

NB

!>          NB is INTEGER
!>          The dimension of the panel to be facotorized.
!> 

A

!>          A is DOUBLE PRECISION array, dimension (LDA,M) for
!>          the first panel, while dimension (LDA,M+1) for the
!>          remaining panels.
!>
!>          On entry, A contains the last row, or column, of
!>          the previous panel, and the trailing submatrix of A
!>          to be factorized, except for the first panel, only
!>          the panel is passed.
!>
!>          On exit, the leading panel is factorized.
!> 

LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= max(1,M).
!> 

IPIV

!>          IPIV is INTEGER array, dimension (M)
!>          Details of the row and column interchanges,
!>          the row and column k were interchanged with the row and
!>          column IPIV(k).
!> 

H

!>          H is DOUBLE PRECISION workspace, dimension (LDH,NB).
!>
!> 

LDH

!>          LDH is INTEGER
!>          The leading dimension of the workspace H. LDH >= max(1,M).
!> 

WORK

!>          WORK is DOUBLE PRECISION workspace, dimension (M).
!> 

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