You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
497 lines
14 KiB
497 lines
14 KiB
2 years ago
|
*> \brief \b CLASYF_AA
|
||
|
|
*
|
||
|
|
* =========== DOCUMENTATION ===========
|
||
|
|
*
|
||
|
|
* Online html documentation available at
|
||
|
|
* http://www.netlib.org/lapack/explore-html/
|
||
|
|
*
|
||
|
|
*> \htmlonly
|
||
|
|
*> Download CLASYF_AA + dependencies
|
||
|
|
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/clasyf_aa.f">
|
||
|
|
*> [TGZ]</a>
|
||
|
|
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/clasyf_aa.f">
|
||
|
|
*> [ZIP]</a>
|
||
|
|
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/clasyf_aa.f">
|
||
|
|
*> [TXT]</a>
|
||
|
|
*> \endhtmlonly
|
||
|
|
*
|
||
|
|
* Definition:
|
||
|
|
* ===========
|
||
|
|
*
|
||
|
|
* SUBROUTINE CLASYF_AA( UPLO, J1, M, NB, A, LDA, IPIV,
|
||
|
|
* H, LDH, WORK )
|
||
|
|
*
|
||
|
|
* .. Scalar Arguments ..
|
||
|
|
* CHARACTER UPLO
|
||
|
|
* INTEGER J1, M, NB, LDA, LDH
|
||
|
|
* ..
|
||
|
|
* .. Array Arguments ..
|
||
|
|
* INTEGER IPIV( * )
|
||
|
|
* COMPLEX A( LDA, * ), H( LDH, * ), WORK( * )
|
||
|
|
* ..
|
||
|
|
*
|
||
|
|
*
|
||
|
|
*> \par Purpose:
|
||
|
|
* =============
|
||
|
|
*>
|
||
|
|
*> \verbatim
|
||
|
|
*>
|
||
|
|
*> DLATRF_AA factorizes a panel of a complex 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.
|
||
|
|
*>
|
||
|
|
*> \endverbatim
|
||
|
|
*
|
||
|
|
* Arguments:
|
||
|
|
* ==========
|
||
|
|
*
|
||
|
|
*> \param[in] UPLO
|
||
|
|
*> \verbatim
|
||
|
|
*> UPLO is CHARACTER*1
|
||
|
|
*> = 'U': Upper triangle of A is stored;
|
||
|
|
*> = 'L': Lower triangle of A is stored.
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in] J1
|
||
|
|
*> \verbatim
|
||
|
|
*> 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 CSYTRF_AA, for the first panel, J1 is 1,
|
||
|
|
*> while for the remaining panels, J1 is 2.
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in] M
|
||
|
|
*> \verbatim
|
||
|
|
*> M is INTEGER
|
||
|
|
*> The dimension of the submatrix. M >= 0.
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in] NB
|
||
|
|
*> \verbatim
|
||
|
|
*> NB is INTEGER
|
||
|
|
*> The dimension of the panel to be facotorized.
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in,out] A
|
||
|
|
*> \verbatim
|
||
|
|
*> A is COMPLEX 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.
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in] LDA
|
||
|
|
*> \verbatim
|
||
|
|
*> LDA is INTEGER
|
||
|
|
*> The leading dimension of the array A. LDA >= max(1,M).
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[out] IPIV
|
||
|
|
*> \verbatim
|
||
|
|
*> 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).
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in,out] H
|
||
|
|
*> \verbatim
|
||
|
|
*> H is COMPLEX workspace, dimension (LDH,NB).
|
||
|
|
*>
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[in] LDH
|
||
|
|
*> \verbatim
|
||
|
|
*> LDH is INTEGER
|
||
|
|
*> The leading dimension of the workspace H. LDH >= max(1,M).
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*> \param[out] WORK
|
||
|
|
*> \verbatim
|
||
|
|
*> WORK is COMPLEX workspace, dimension (M).
|
||
|
|
*> \endverbatim
|
||
|
|
*>
|
||
|
|
*
|
||
|
|
* Authors:
|
||
|
|
* ========
|
||
|
|
*
|
||
|
|
*> \author Univ. of Tennessee
|
||
|
|
*> \author Univ. of California Berkeley
|
||
|
|
*> \author Univ. of Colorado Denver
|
||
|
|
*> \author NAG Ltd.
|
||
|
|
*
|
||
|
|
*> \ingroup complexSYcomputational
|
||
|
|
*
|
||
|
|
* =====================================================================
|
||
|
|
SUBROUTINE CLASYF_AA( UPLO, J1, M, NB, A, LDA, IPIV,
|
||
|
|
$ H, LDH, WORK )
|
||
|
|
*
|
||
|
|
* -- LAPACK computational routine --
|
||
|
|
* -- LAPACK is a software package provided by Univ. of Tennessee, --
|
||
|
|
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
|
||
|
|
*
|
||
|
|
IMPLICIT NONE
|
||
|
|
*
|
||
|
|
* .. Scalar Arguments ..
|
||
|
|
CHARACTER UPLO
|
||
|
|
INTEGER M, NB, J1, LDA, LDH
|
||
|
|
* ..
|
||
|
|
* .. Array Arguments ..
|
||
|
|
INTEGER IPIV( * )
|
||
|
|
COMPLEX A( LDA, * ), H( LDH, * ), WORK( * )
|
||
|
|
* ..
|
||
|
|
*
|
||
|
|
* =====================================================================
|
||
|
|
* .. Parameters ..
|
||
|
|
COMPLEX ZERO, ONE
|
||
|
|
PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
|
||
|
|
*
|
||
|
|
* .. Local Scalars ..
|
||
|
|
INTEGER J, K, K1, I1, I2, MJ
|
||
|
|
COMPLEX PIV, ALPHA
|
||
|
|
* ..
|
||
|
|
* .. External Functions ..
|
||
|
|
LOGICAL LSAME
|
||
|
|
INTEGER ICAMAX, ILAENV
|
||
|
|
EXTERNAL LSAME, ILAENV, ICAMAX
|
||
|
|
* ..
|
||
|
|
* .. External Subroutines ..
|
||
|
|
EXTERNAL CAXPY, CGEMV, CSCAL, CCOPY, CSWAP, CLASET,
|
||
|
|
$ XERBLA
|
||
|
|
* ..
|
||
|
|
* .. Intrinsic Functions ..
|
||
|
|
INTRINSIC MAX
|
||
|
|
* ..
|
||
|
|
* .. Executable Statements ..
|
||
|
|
*
|
||
|
|
J = 1
|
||
|
|
*
|
||
|
|
* K1 is the first column of the panel to be factorized
|
||
|
|
* i.e., K1 is 2 for the first block column, and 1 for the rest of the blocks
|
||
|
|
*
|
||
|
|
K1 = (2-J1)+1
|
||
|
|
*
|
||
|
|
IF( LSAME( UPLO, 'U' ) ) THEN
|
||
|
|
*
|
||
|
|
* .....................................................
|
||
|
|
* Factorize A as U**T*D*U using the upper triangle of A
|
||
|
|
* .....................................................
|
||
|
|
*
|
||
|
|
10 CONTINUE
|
||
|
|
IF ( J.GT.MIN(M, NB) )
|
||
|
|
$ GO TO 20
|
||
|
|
*
|
||
|
|
* K is the column to be factorized
|
||
|
|
* when being called from CSYTRF_AA,
|
||
|
|
* > for the first block column, J1 is 1, hence J1+J-1 is J,
|
||
|
|
* > for the rest of the columns, J1 is 2, and J1+J-1 is J+1,
|
||
|
|
*
|
||
|
|
K = J1+J-1
|
||
|
|
IF( J.EQ.M ) THEN
|
||
|
|
*
|
||
|
|
* Only need to compute T(J, J)
|
||
|
|
*
|
||
|
|
MJ = 1
|
||
|
|
ELSE
|
||
|
|
MJ = M-J+1
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* H(J:M, J) := A(J, J:M) - H(J:M, 1:(J-1)) * L(J1:(J-1), J),
|
||
|
|
* where H(J:M, J) has been initialized to be A(J, J:M)
|
||
|
|
*
|
||
|
|
IF( K.GT.2 ) THEN
|
||
|
|
*
|
||
|
|
* K is the column to be factorized
|
||
|
|
* > for the first block column, K is J, skipping the first two
|
||
|
|
* columns
|
||
|
|
* > for the rest of the columns, K is J+1, skipping only the
|
||
|
|
* first column
|
||
|
|
*
|
||
|
|
CALL CGEMV( 'No transpose', MJ, J-K1,
|
||
|
|
$ -ONE, H( J, K1 ), LDH,
|
||
|
|
$ A( 1, J ), 1,
|
||
|
|
$ ONE, H( J, J ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Copy H(i:M, i) into WORK
|
||
|
|
*
|
||
|
|
CALL CCOPY( MJ, H( J, J ), 1, WORK( 1 ), 1 )
|
||
|
|
*
|
||
|
|
IF( J.GT.K1 ) THEN
|
||
|
|
*
|
||
|
|
* Compute WORK := WORK - L(J-1, J:M) * T(J-1,J),
|
||
|
|
* where A(J-1, J) stores T(J-1, J) and A(J-2, J:M) stores U(J-1, J:M)
|
||
|
|
*
|
||
|
|
ALPHA = -A( K-1, J )
|
||
|
|
CALL CAXPY( MJ, ALPHA, A( K-2, J ), LDA, WORK( 1 ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Set A(J, J) = T(J, J)
|
||
|
|
*
|
||
|
|
A( K, J ) = WORK( 1 )
|
||
|
|
*
|
||
|
|
IF( J.LT.M ) THEN
|
||
|
|
*
|
||
|
|
* Compute WORK(2:M) = T(J, J) L(J, (J+1):M)
|
||
|
|
* where A(J, J) stores T(J, J) and A(J-1, (J+1):M) stores U(J, (J+1):M)
|
||
|
|
*
|
||
|
|
IF( K.GT.1 ) THEN
|
||
|
|
ALPHA = -A( K, J )
|
||
|
|
CALL CAXPY( M-J, ALPHA, A( K-1, J+1 ), LDA,
|
||
|
|
$ WORK( 2 ), 1 )
|
||
|
|
ENDIF
|
||
|
|
*
|
||
|
|
* Find max(|WORK(2:M)|)
|
||
|
|
*
|
||
|
|
I2 = ICAMAX( M-J, WORK( 2 ), 1 ) + 1
|
||
|
|
PIV = WORK( I2 )
|
||
|
|
*
|
||
|
|
* Apply symmetric pivot
|
||
|
|
*
|
||
|
|
IF( (I2.NE.2) .AND. (PIV.NE.0) ) THEN
|
||
|
|
*
|
||
|
|
* Swap WORK(I1) and WORK(I2)
|
||
|
|
*
|
||
|
|
I1 = 2
|
||
|
|
WORK( I2 ) = WORK( I1 )
|
||
|
|
WORK( I1 ) = PIV
|
||
|
|
*
|
||
|
|
* Swap A(I1, I1+1:M) with A(I1+1:M, I2)
|
||
|
|
*
|
||
|
|
I1 = I1+J-1
|
||
|
|
I2 = I2+J-1
|
||
|
|
CALL CSWAP( I2-I1-1, A( J1+I1-1, I1+1 ), LDA,
|
||
|
|
$ A( J1+I1, I2 ), 1 )
|
||
|
|
*
|
||
|
|
* Swap A(I1, I2+1:M) with A(I2, I2+1:M)
|
||
|
|
*
|
||
|
|
IF( I2.LT.M )
|
||
|
|
$ CALL CSWAP( M-I2, A( J1+I1-1, I2+1 ), LDA,
|
||
|
|
$ A( J1+I2-1, I2+1 ), LDA )
|
||
|
|
*
|
||
|
|
* Swap A(I1, I1) with A(I2,I2)
|
||
|
|
*
|
||
|
|
PIV = A( I1+J1-1, I1 )
|
||
|
|
A( J1+I1-1, I1 ) = A( J1+I2-1, I2 )
|
||
|
|
A( J1+I2-1, I2 ) = PIV
|
||
|
|
*
|
||
|
|
* Swap H(I1, 1:J1) with H(I2, 1:J1)
|
||
|
|
*
|
||
|
|
CALL CSWAP( I1-1, H( I1, 1 ), LDH, H( I2, 1 ), LDH )
|
||
|
|
IPIV( I1 ) = I2
|
||
|
|
*
|
||
|
|
IF( I1.GT.(K1-1) ) THEN
|
||
|
|
*
|
||
|
|
* Swap L(1:I1-1, I1) with L(1:I1-1, I2),
|
||
|
|
* skipping the first column
|
||
|
|
*
|
||
|
|
CALL CSWAP( I1-K1+1, A( 1, I1 ), 1,
|
||
|
|
$ A( 1, I2 ), 1 )
|
||
|
|
END IF
|
||
|
|
ELSE
|
||
|
|
IPIV( J+1 ) = J+1
|
||
|
|
ENDIF
|
||
|
|
*
|
||
|
|
* Set A(J, J+1) = T(J, J+1)
|
||
|
|
*
|
||
|
|
A( K, J+1 ) = WORK( 2 )
|
||
|
|
*
|
||
|
|
IF( J.LT.NB ) THEN
|
||
|
|
*
|
||
|
|
* Copy A(J+1:M, J+1) into H(J:M, J),
|
||
|
|
*
|
||
|
|
CALL CCOPY( M-J, A( K+1, J+1 ), LDA,
|
||
|
|
$ H( J+1, J+1 ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Compute L(J+2, J+1) = WORK( 3:M ) / T(J, J+1),
|
||
|
|
* where A(J, J+1) = T(J, J+1) and A(J+2:M, J) = L(J+2:M, J+1)
|
||
|
|
*
|
||
|
|
IF( J.LT.(M-1) ) THEN
|
||
|
|
IF( A( K, J+1 ).NE.ZERO ) THEN
|
||
|
|
ALPHA = ONE / A( K, J+1 )
|
||
|
|
CALL CCOPY( M-J-1, WORK( 3 ), 1, A( K, J+2 ), LDA )
|
||
|
|
CALL CSCAL( M-J-1, ALPHA, A( K, J+2 ), LDA )
|
||
|
|
ELSE
|
||
|
|
CALL CLASET( 'Full', 1, M-J-1, ZERO, ZERO,
|
||
|
|
$ A( K, J+2 ), LDA)
|
||
|
|
END IF
|
||
|
|
END IF
|
||
|
|
END IF
|
||
|
|
J = J + 1
|
||
|
|
GO TO 10
|
||
|
|
20 CONTINUE
|
||
|
|
*
|
||
|
|
ELSE
|
||
|
|
*
|
||
|
|
* .....................................................
|
||
|
|
* Factorize A as L*D*L**T using the lower triangle of A
|
||
|
|
* .....................................................
|
||
|
|
*
|
||
|
|
30 CONTINUE
|
||
|
|
IF( J.GT.MIN( M, NB ) )
|
||
|
|
$ GO TO 40
|
||
|
|
*
|
||
|
|
* K is the column to be factorized
|
||
|
|
* when being called from CSYTRF_AA,
|
||
|
|
* > for the first block column, J1 is 1, hence J1+J-1 is J,
|
||
|
|
* > for the rest of the columns, J1 is 2, and J1+J-1 is J+1,
|
||
|
|
*
|
||
|
|
K = J1+J-1
|
||
|
|
IF( J.EQ.M ) THEN
|
||
|
|
*
|
||
|
|
* Only need to compute T(J, J)
|
||
|
|
*
|
||
|
|
MJ = 1
|
||
|
|
ELSE
|
||
|
|
MJ = M-J+1
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* H(J:M, J) := A(J:M, J) - H(J:M, 1:(J-1)) * L(J, J1:(J-1))^T,
|
||
|
|
* where H(J:M, J) has been initialized to be A(J:M, J)
|
||
|
|
*
|
||
|
|
IF( K.GT.2 ) THEN
|
||
|
|
*
|
||
|
|
* K is the column to be factorized
|
||
|
|
* > for the first block column, K is J, skipping the first two
|
||
|
|
* columns
|
||
|
|
* > for the rest of the columns, K is J+1, skipping only the
|
||
|
|
* first column
|
||
|
|
*
|
||
|
|
CALL CGEMV( 'No transpose', MJ, J-K1,
|
||
|
|
$ -ONE, H( J, K1 ), LDH,
|
||
|
|
$ A( J, 1 ), LDA,
|
||
|
|
$ ONE, H( J, J ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Copy H(J:M, J) into WORK
|
||
|
|
*
|
||
|
|
CALL CCOPY( MJ, H( J, J ), 1, WORK( 1 ), 1 )
|
||
|
|
*
|
||
|
|
IF( J.GT.K1 ) THEN
|
||
|
|
*
|
||
|
|
* Compute WORK := WORK - L(J:M, J-1) * T(J-1,J),
|
||
|
|
* where A(J-1, J) = T(J-1, J) and A(J, J-2) = L(J, J-1)
|
||
|
|
*
|
||
|
|
ALPHA = -A( J, K-1 )
|
||
|
|
CALL CAXPY( MJ, ALPHA, A( J, K-2 ), 1, WORK( 1 ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Set A(J, J) = T(J, J)
|
||
|
|
*
|
||
|
|
A( J, K ) = WORK( 1 )
|
||
|
|
*
|
||
|
|
IF( J.LT.M ) THEN
|
||
|
|
*
|
||
|
|
* Compute WORK(2:M) = T(J, J) L((J+1):M, J)
|
||
|
|
* where A(J, J) = T(J, J) and A((J+1):M, J-1) = L((J+1):M, J)
|
||
|
|
*
|
||
|
|
IF( K.GT.1 ) THEN
|
||
|
|
ALPHA = -A( J, K )
|
||
|
|
CALL CAXPY( M-J, ALPHA, A( J+1, K-1 ), 1,
|
||
|
|
$ WORK( 2 ), 1 )
|
||
|
|
ENDIF
|
||
|
|
*
|
||
|
|
* Find max(|WORK(2:M)|)
|
||
|
|
*
|
||
|
|
I2 = ICAMAX( M-J, WORK( 2 ), 1 ) + 1
|
||
|
|
PIV = WORK( I2 )
|
||
|
|
*
|
||
|
|
* Apply symmetric pivot
|
||
|
|
*
|
||
|
|
IF( (I2.NE.2) .AND. (PIV.NE.0) ) THEN
|
||
|
|
*
|
||
|
|
* Swap WORK(I1) and WORK(I2)
|
||
|
|
*
|
||
|
|
I1 = 2
|
||
|
|
WORK( I2 ) = WORK( I1 )
|
||
|
|
WORK( I1 ) = PIV
|
||
|
|
*
|
||
|
|
* Swap A(I1+1:M, I1) with A(I2, I1+1:M)
|
||
|
|
*
|
||
|
|
I1 = I1+J-1
|
||
|
|
I2 = I2+J-1
|
||
|
|
CALL CSWAP( I2-I1-1, A( I1+1, J1+I1-1 ), 1,
|
||
|
|
$ A( I2, J1+I1 ), LDA )
|
||
|
|
*
|
||
|
|
* Swap A(I2+1:M, I1) with A(I2+1:M, I2)
|
||
|
|
*
|
||
|
|
IF( I2.LT.M )
|
||
|
|
$ CALL CSWAP( M-I2, A( I2+1, J1+I1-1 ), 1,
|
||
|
|
$ A( I2+1, J1+I2-1 ), 1 )
|
||
|
|
*
|
||
|
|
* Swap A(I1, I1) with A(I2, I2)
|
||
|
|
*
|
||
|
|
PIV = A( I1, J1+I1-1 )
|
||
|
|
A( I1, J1+I1-1 ) = A( I2, J1+I2-1 )
|
||
|
|
A( I2, J1+I2-1 ) = PIV
|
||
|
|
*
|
||
|
|
* Swap H(I1, I1:J1) with H(I2, I2:J1)
|
||
|
|
*
|
||
|
|
CALL CSWAP( I1-1, H( I1, 1 ), LDH, H( I2, 1 ), LDH )
|
||
|
|
IPIV( I1 ) = I2
|
||
|
|
*
|
||
|
|
IF( I1.GT.(K1-1) ) THEN
|
||
|
|
*
|
||
|
|
* Swap L(1:I1-1, I1) with L(1:I1-1, I2),
|
||
|
|
* skipping the first column
|
||
|
|
*
|
||
|
|
CALL CSWAP( I1-K1+1, A( I1, 1 ), LDA,
|
||
|
|
$ A( I2, 1 ), LDA )
|
||
|
|
END IF
|
||
|
|
ELSE
|
||
|
|
IPIV( J+1 ) = J+1
|
||
|
|
ENDIF
|
||
|
|
*
|
||
|
|
* Set A(J+1, J) = T(J+1, J)
|
||
|
|
*
|
||
|
|
A( J+1, K ) = WORK( 2 )
|
||
|
|
*
|
||
|
|
IF( J.LT.NB ) THEN
|
||
|
|
*
|
||
|
|
* Copy A(J+1:M, J+1) into H(J+1:M, J),
|
||
|
|
*
|
||
|
|
CALL CCOPY( M-J, A( J+1, K+1 ), 1,
|
||
|
|
$ H( J+1, J+1 ), 1 )
|
||
|
|
END IF
|
||
|
|
*
|
||
|
|
* Compute L(J+2, J+1) = WORK( 3:M ) / T(J, J+1),
|
||
|
|
* where A(J, J+1) = T(J, J+1) and A(J+2:M, J) = L(J+2:M, J+1)
|
||
|
|
*
|
||
|
|
IF( J.LT.(M-1) ) THEN
|
||
|
|
IF( A( J+1, K ).NE.ZERO ) THEN
|
||
|
|
ALPHA = ONE / A( J+1, K )
|
||
|
|
CALL CCOPY( M-J-1, WORK( 3 ), 1, A( J+2, K ), 1 )
|
||
|
|
CALL CSCAL( M-J-1, ALPHA, A( J+2, K ), 1 )
|
||
|
|
ELSE
|
||
|
|
CALL CLASET( 'Full', M-J-1, 1, ZERO, ZERO,
|
||
|
|
$ A( J+2, K ), LDA )
|
||
|
|
END IF
|
||
|
|
END IF
|
||
|
|
END IF
|
||
|
|
J = J + 1
|
||
|
|
GO TO 30
|
||
|
|
40 CONTINUE
|
||
|
|
END IF
|
||
|
|
RETURN
|
||
|
|
*
|
||
|
|
* End of CLASYF_AA
|
||
|
|
*
|
||
|
|
END
|