Refs #247. Included lapack source codes. Avoid downloading tar.gz from netlib.org
Based on 3.4.2 version, apply patch.for_lapack-3.4.2.
This commit is contained in:
Zhang Xianyi
243
lapack-netlib/SRC/dlarrc.f
Normal file
243
lapack-netlib/SRC/dlarrc.f
Normal file
@@ -0,0 +1,243 @@
|
||||
*> \brief \b DLARRC computes the number of eigenvalues of the symmetric tridiagonal matrix.
|
||||
*
|
||||
* =========== DOCUMENTATION ===========
|
||||
*
|
||||
* Online html documentation available at
|
||||
* http://www.netlib.org/lapack/explore-html/
|
||||
*
|
||||
*> \htmlonly
|
||||
*> Download DLARRC + dependencies
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlarrc.f">
|
||||
*> [TGZ]</a>
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlarrc.f">
|
||||
*> [ZIP]</a>
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlarrc.f">
|
||||
*> [TXT]</a>
|
||||
*> \endhtmlonly
|
||||
*
|
||||
* Definition:
|
||||
* ===========
|
||||
*
|
||||
* SUBROUTINE DLARRC( JOBT, N, VL, VU, D, E, PIVMIN,
|
||||
* EIGCNT, LCNT, RCNT, INFO )
|
||||
*
|
||||
* .. Scalar Arguments ..
|
||||
* CHARACTER JOBT
|
||||
* INTEGER EIGCNT, INFO, LCNT, N, RCNT
|
||||
* DOUBLE PRECISION PIVMIN, VL, VU
|
||||
* ..
|
||||
* .. Array Arguments ..
|
||||
* DOUBLE PRECISION D( * ), E( * )
|
||||
* ..
|
||||
*
|
||||
*
|
||||
*> \par Purpose:
|
||||
* =============
|
||||
*>
|
||||
*> \verbatim
|
||||
*>
|
||||
*> Find the number of eigenvalues of the symmetric tridiagonal matrix T
|
||||
*> that are in the interval (VL,VU] if JOBT = 'T', and of L D L^T
|
||||
*> if JOBT = 'L'.
|
||||
*> \endverbatim
|
||||
*
|
||||
* Arguments:
|
||||
* ==========
|
||||
*
|
||||
*> \param[in] JOBT
|
||||
*> \verbatim
|
||||
*> JOBT is CHARACTER*1
|
||||
*> = 'T': Compute Sturm count for matrix T.
|
||||
*> = 'L': Compute Sturm count for matrix L D L^T.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] N
|
||||
*> \verbatim
|
||||
*> N is INTEGER
|
||||
*> The order of the matrix. N > 0.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] VL
|
||||
*> \verbatim
|
||||
*> VL is DOUBLE PRECISION
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] VU
|
||||
*> \verbatim
|
||||
*> VU is DOUBLE PRECISION
|
||||
*> The lower and upper bounds for the eigenvalues.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] D
|
||||
*> \verbatim
|
||||
*> D is DOUBLE PRECISION array, dimension (N)
|
||||
*> JOBT = 'T': The N diagonal elements of the tridiagonal matrix T.
|
||||
*> JOBT = 'L': The N diagonal elements of the diagonal matrix D.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] E
|
||||
*> \verbatim
|
||||
*> E is DOUBLE PRECISION array, dimension (N)
|
||||
*> JOBT = 'T': The N-1 offdiagonal elements of the matrix T.
|
||||
*> JOBT = 'L': The N-1 offdiagonal elements of the matrix L.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] PIVMIN
|
||||
*> \verbatim
|
||||
*> PIVMIN is DOUBLE PRECISION
|
||||
*> The minimum pivot in the Sturm sequence for T.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] EIGCNT
|
||||
*> \verbatim
|
||||
*> EIGCNT is INTEGER
|
||||
*> The number of eigenvalues of the symmetric tridiagonal matrix T
|
||||
*> that are in the interval (VL,VU]
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] LCNT
|
||||
*> \verbatim
|
||||
*> LCNT is INTEGER
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] RCNT
|
||||
*> \verbatim
|
||||
*> RCNT is INTEGER
|
||||
*> The left and right negcounts of the interval.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] INFO
|
||||
*> \verbatim
|
||||
*> INFO is INTEGER
|
||||
*> \endverbatim
|
||||
*
|
||||
* Authors:
|
||||
* ========
|
||||
*
|
||||
*> \author Univ. of Tennessee
|
||||
*> \author Univ. of California Berkeley
|
||||
*> \author Univ. of Colorado Denver
|
||||
*> \author NAG Ltd.
|
||||
*
|
||||
*> \date September 2012
|
||||
*
|
||||
*> \ingroup auxOTHERauxiliary
|
||||
*
|
||||
*> \par Contributors:
|
||||
* ==================
|
||||
*>
|
||||
*> Beresford Parlett, University of California, Berkeley, USA \n
|
||||
*> Jim Demmel, University of California, Berkeley, USA \n
|
||||
*> Inderjit Dhillon, University of Texas, Austin, USA \n
|
||||
*> Osni Marques, LBNL/NERSC, USA \n
|
||||
*> Christof Voemel, University of California, Berkeley, USA
|
||||
*
|
||||
* =====================================================================
|
||||
SUBROUTINE DLARRC( JOBT, N, VL, VU, D, E, PIVMIN,
|
||||
$ EIGCNT, LCNT, RCNT, INFO )
|
||||
*
|
||||
* -- LAPACK auxiliary routine (version 3.4.2) --
|
||||
* -- LAPACK is a software package provided by Univ. of Tennessee, --
|
||||
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
|
||||
* September 2012
|
||||
*
|
||||
* .. Scalar Arguments ..
|
||||
CHARACTER JOBT
|
||||
INTEGER EIGCNT, INFO, LCNT, N, RCNT
|
||||
DOUBLE PRECISION PIVMIN, VL, VU
|
||||
* ..
|
||||
* .. Array Arguments ..
|
||||
DOUBLE PRECISION D( * ), E( * )
|
||||
* ..
|
||||
*
|
||||
* =====================================================================
|
||||
*
|
||||
* .. Parameters ..
|
||||
DOUBLE PRECISION ZERO
|
||||
PARAMETER ( ZERO = 0.0D0 )
|
||||
* ..
|
||||
* .. Local Scalars ..
|
||||
INTEGER I
|
||||
LOGICAL MATT
|
||||
DOUBLE PRECISION LPIVOT, RPIVOT, SL, SU, TMP, TMP2
|
||||
|
||||
* ..
|
||||
* .. External Functions ..
|
||||
LOGICAL LSAME
|
||||
EXTERNAL LSAME
|
||||
* ..
|
||||
* .. Executable Statements ..
|
||||
*
|
||||
INFO = 0
|
||||
LCNT = 0
|
||||
RCNT = 0
|
||||
EIGCNT = 0
|
||||
MATT = LSAME( JOBT, 'T' )
|
||||
|
||||
|
||||
IF (MATT) THEN
|
||||
* Sturm sequence count on T
|
||||
LPIVOT = D( 1 ) - VL
|
||||
RPIVOT = D( 1 ) - VU
|
||||
IF( LPIVOT.LE.ZERO ) THEN
|
||||
LCNT = LCNT + 1
|
||||
ENDIF
|
||||
IF( RPIVOT.LE.ZERO ) THEN
|
||||
RCNT = RCNT + 1
|
||||
ENDIF
|
||||
DO 10 I = 1, N-1
|
||||
TMP = E(I)**2
|
||||
LPIVOT = ( D( I+1 )-VL ) - TMP/LPIVOT
|
||||
RPIVOT = ( D( I+1 )-VU ) - TMP/RPIVOT
|
||||
IF( LPIVOT.LE.ZERO ) THEN
|
||||
LCNT = LCNT + 1
|
||||
ENDIF
|
||||
IF( RPIVOT.LE.ZERO ) THEN
|
||||
RCNT = RCNT + 1
|
||||
ENDIF
|
||||
10 CONTINUE
|
||||
ELSE
|
||||
* Sturm sequence count on L D L^T
|
||||
SL = -VL
|
||||
SU = -VU
|
||||
DO 20 I = 1, N - 1
|
||||
LPIVOT = D( I ) + SL
|
||||
RPIVOT = D( I ) + SU
|
||||
IF( LPIVOT.LE.ZERO ) THEN
|
||||
LCNT = LCNT + 1
|
||||
ENDIF
|
||||
IF( RPIVOT.LE.ZERO ) THEN
|
||||
RCNT = RCNT + 1
|
||||
ENDIF
|
||||
TMP = E(I) * D(I) * E(I)
|
||||
*
|
||||
TMP2 = TMP / LPIVOT
|
||||
IF( TMP2.EQ.ZERO ) THEN
|
||||
SL = TMP - VL
|
||||
ELSE
|
||||
SL = SL*TMP2 - VL
|
||||
END IF
|
||||
*
|
||||
TMP2 = TMP / RPIVOT
|
||||
IF( TMP2.EQ.ZERO ) THEN
|
||||
SU = TMP - VU
|
||||
ELSE
|
||||
SU = SU*TMP2 - VU
|
||||
END IF
|
||||
20 CONTINUE
|
||||
LPIVOT = D( N ) + SL
|
||||
RPIVOT = D( N ) + SU
|
||||
IF( LPIVOT.LE.ZERO ) THEN
|
||||
LCNT = LCNT + 1
|
||||
ENDIF
|
||||
IF( RPIVOT.LE.ZERO ) THEN
|
||||
RCNT = RCNT + 1
|
||||
ENDIF
|
||||
ENDIF
|
||||
EIGCNT = RCNT - LCNT
|
||||
|
||||
RETURN
|
||||
*
|
||||
* end of DLARRC
|
||||
*
|
||||
END
|
||||
Reference in New Issue
Block a user