--- rpl/lapack/lapack/dgsvj1.f 2011/07/22 07:38:05 1.6
+++ rpl/lapack/lapack/dgsvj1.f 2023/08/07 08:38:51 1.22
@@ -1,22 +1,243 @@
- SUBROUTINE DGSVJ1( JOBV, M, N, N1, A, LDA, D, SVA, MV, V, LDV,
- $ EPS, SFMIN, TOL, NSWEEP, WORK, LWORK, INFO )
+*> \brief \b DGSVJ1 pre-processor for the routine dgesvj, applies Jacobi rotations targeting only particular pivots.
+*
+* =========== DOCUMENTATION ===========
*
-* -- LAPACK routine (version 3.3.1) --
+* Online html documentation available at
+* http://www.netlib.org/lapack/explore-html/
*
-* -- Contributed by Zlatko Drmac of the University of Zagreb and --
-* -- Kresimir Veselic of the Fernuniversitaet Hagen --
-* -- April 2011 --
+*> \htmlonly
+*> Download DGSVJ1 + dependencies
+*>
+*> [TGZ]
+*>
+*> [ZIP]
+*>
+*> [TXT]
+*> \endhtmlonly
+*
+* Definition:
+* ===========
+*
+* SUBROUTINE DGSVJ1( JOBV, M, N, N1, A, LDA, D, SVA, MV, V, LDV,
+* EPS, SFMIN, TOL, NSWEEP, WORK, LWORK, INFO )
+*
+* .. Scalar Arguments ..
+* DOUBLE PRECISION EPS, SFMIN, TOL
+* INTEGER INFO, LDA, LDV, LWORK, M, MV, N, N1, NSWEEP
+* CHARACTER*1 JOBV
+* ..
+* .. Array Arguments ..
+* DOUBLE PRECISION A( LDA, * ), D( N ), SVA( N ), V( LDV, * ),
+* $ WORK( LWORK )
+* ..
+*
+*
+*> \par Purpose:
+* =============
+*>
+*> \verbatim
+*>
+*> DGSVJ1 is called from DGESVJ as a pre-processor and that is its main
+*> purpose. It applies Jacobi rotations in the same way as DGESVJ does, but
+*> it targets only particular pivots and it does not check convergence
+*> (stopping criterion). Few tuning parameters (marked by [TP]) are
+*> available for the implementer.
+*>
+*> Further Details
+*> ~~~~~~~~~~~~~~~
+*> DGSVJ1 applies few sweeps of Jacobi rotations in the column space of
+*> the input M-by-N matrix A. The pivot pairs are taken from the (1,2)
+*> off-diagonal block in the corresponding N-by-N Gram matrix A^T * A. The
+*> block-entries (tiles) of the (1,2) off-diagonal block are marked by the
+*> [x]'s in the following scheme:
+*>
+*> | * * * [x] [x] [x]|
+*> | * * * [x] [x] [x]| Row-cycling in the nblr-by-nblc [x] blocks.
+*> | * * * [x] [x] [x]| Row-cyclic pivoting inside each [x] block.
+*> |[x] [x] [x] * * * |
+*> |[x] [x] [x] * * * |
+*> |[x] [x] [x] * * * |
+*>
+*> In terms of the columns of A, the first N1 columns are rotated 'against'
+*> the remaining N-N1 columns, trying to increase the angle between the
+*> corresponding subspaces. The off-diagonal block is N1-by(N-N1) and it is
+*> tiled using quadratic tiles of side KBL. Here, KBL is a tuning parameter.
+*> The number of sweeps is given in NSWEEP and the orthogonality threshold
+*> is given in TOL.
+*> \endverbatim
+*
+* Arguments:
+* ==========
+*
+*> \param[in] JOBV
+*> \verbatim
+*> JOBV is CHARACTER*1
+*> Specifies whether the output from this procedure is used
+*> to compute the matrix V:
+*> = 'V': the product of the Jacobi rotations is accumulated
+*> by postmulyiplying the N-by-N array V.
+*> (See the description of V.)
+*> = 'A': the product of the Jacobi rotations is accumulated
+*> by postmulyiplying the MV-by-N array V.
+*> (See the descriptions of MV and V.)
+*> = 'N': the Jacobi rotations are not accumulated.
+*> \endverbatim
+*>
+*> \param[in] M
+*> \verbatim
+*> M is INTEGER
+*> The number of rows of the input matrix A. M >= 0.
+*> \endverbatim
+*>
+*> \param[in] N
+*> \verbatim
+*> N is INTEGER
+*> The number of columns of the input matrix A.
+*> M >= N >= 0.
+*> \endverbatim
+*>
+*> \param[in] N1
+*> \verbatim
+*> N1 is INTEGER
+*> N1 specifies the 2 x 2 block partition, the first N1 columns are
+*> rotated 'against' the remaining N-N1 columns of A.
+*> \endverbatim
+*>
+*> \param[in,out] A
+*> \verbatim
+*> A is DOUBLE PRECISION array, dimension (LDA,N)
+*> On entry, M-by-N matrix A, such that A*diag(D) represents
+*> the input matrix.
+*> On exit,
+*> A_onexit * D_onexit represents the input matrix A*diag(D)
+*> post-multiplied by a sequence of Jacobi rotations, where the
+*> rotation threshold and the total number of sweeps are given in
+*> TOL and NSWEEP, respectively.
+*> (See the descriptions of N1, D, TOL and NSWEEP.)
+*> \endverbatim
+*>
+*> \param[in] LDA
+*> \verbatim
+*> LDA is INTEGER
+*> The leading dimension of the array A. LDA >= max(1,M).
+*> \endverbatim
+*>
+*> \param[in,out] D
+*> \verbatim
+*> D is DOUBLE PRECISION array, dimension (N)
+*> The array D accumulates the scaling factors from the fast scaled
+*> Jacobi rotations.
+*> On entry, A*diag(D) represents the input matrix.
+*> On exit, A_onexit*diag(D_onexit) represents the input matrix
+*> post-multiplied by a sequence of Jacobi rotations, where the
+*> rotation threshold and the total number of sweeps are given in
+*> TOL and NSWEEP, respectively.
+*> (See the descriptions of N1, A, TOL and NSWEEP.)
+*> \endverbatim
+*>
+*> \param[in,out] SVA
+*> \verbatim
+*> SVA is DOUBLE PRECISION array, dimension (N)
+*> On entry, SVA contains the Euclidean norms of the columns of
+*> the matrix A*diag(D).
+*> On exit, SVA contains the Euclidean norms of the columns of
+*> the matrix onexit*diag(D_onexit).
+*> \endverbatim
+*>
+*> \param[in] MV
+*> \verbatim
+*> MV is INTEGER
+*> If JOBV = 'A', then MV rows of V are post-multipled by a
+*> sequence of Jacobi rotations.
+*> If JOBV = 'N', then MV is not referenced.
+*> \endverbatim
+*>
+*> \param[in,out] V
+*> \verbatim
+*> V is DOUBLE PRECISION array, dimension (LDV,N)
+*> If JOBV = 'V', then N rows of V are post-multipled by a
+*> sequence of Jacobi rotations.
+*> If JOBV = 'A', then MV rows of V are post-multipled by a
+*> sequence of Jacobi rotations.
+*> If JOBV = 'N', then V is not referenced.
+*> \endverbatim
+*>
+*> \param[in] LDV
+*> \verbatim
+*> LDV is INTEGER
+*> The leading dimension of the array V, LDV >= 1.
+*> If JOBV = 'V', LDV >= N.
+*> If JOBV = 'A', LDV >= MV.
+*> \endverbatim
+*>
+*> \param[in] EPS
+*> \verbatim
+*> EPS is DOUBLE PRECISION
+*> EPS = DLAMCH('Epsilon')
+*> \endverbatim
+*>
+*> \param[in] SFMIN
+*> \verbatim
+*> SFMIN is DOUBLE PRECISION
+*> SFMIN = DLAMCH('Safe Minimum')
+*> \endverbatim
+*>
+*> \param[in] TOL
+*> \verbatim
+*> TOL is DOUBLE PRECISION
+*> TOL is the threshold for Jacobi rotations. For a pair
+*> A(:,p), A(:,q) of pivot columns, the Jacobi rotation is
+*> applied only if DABS(COS(angle(A(:,p),A(:,q)))) > TOL.
+*> \endverbatim
+*>
+*> \param[in] NSWEEP
+*> \verbatim
+*> NSWEEP is INTEGER
+*> NSWEEP is the number of sweeps of Jacobi rotations to be
+*> performed.
+*> \endverbatim
+*>
+*> \param[out] WORK
+*> \verbatim
+*> WORK is DOUBLE PRECISION array, dimension (LWORK)
+*> \endverbatim
+*>
+*> \param[in] LWORK
+*> \verbatim
+*> LWORK is INTEGER
+*> LWORK is the dimension of WORK. LWORK >= M.
+*> \endverbatim
+*>
+*> \param[out] INFO
+*> \verbatim
+*> INFO is INTEGER
+*> = 0: successful exit.
+*> < 0: if INFO = -i, then the i-th argument had an illegal value
+*> \endverbatim
+*
+* Authors:
+* ========
+*
+*> \author Univ. of Tennessee
+*> \author Univ. of California Berkeley
+*> \author Univ. of Colorado Denver
+*> \author NAG Ltd.
+*
+*> \ingroup doubleOTHERcomputational
+*
+*> \par Contributors:
+* ==================
+*>
+*> Zlatko Drmac (Zagreb, Croatia) and Kresimir Veselic (Hagen, Germany)
+*
+* =====================================================================
+ SUBROUTINE DGSVJ1( JOBV, M, N, N1, A, LDA, D, SVA, MV, V, LDV,
+ $ EPS, SFMIN, TOL, NSWEEP, WORK, LWORK, INFO )
*
+* -- LAPACK computational routine --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
-* This routine is also part of SIGMA (version 1.23, October 23. 2008.)
-* SIGMA is a library of algorithms for highly accurate algorithms for
-* computation of SVD, PSVD, QSVD, (H,K)-SVD, and for solution of the
-* eigenvalue problems Hx = lambda M x, H M x = lambda x with H, M > 0.
-*
- IMPLICIT NONE
-* ..
* .. Scalar Arguments ..
DOUBLE PRECISION EPS, SFMIN, TOL
INTEGER INFO, LDA, LDV, LWORK, M, MV, N, N1, NSWEEP
@@ -27,142 +248,11 @@
$ WORK( LWORK )
* ..
*
-* Purpose
-* =======
-*
-* DGSVJ1 is called from SGESVJ as a pre-processor and that is its main
-* purpose. It applies Jacobi rotations in the same way as SGESVJ does, but
-* it targets only particular pivots and it does not check convergence
-* (stopping criterion). Few tunning parameters (marked by [TP]) are
-* available for the implementer.
-*
-* Further Details
-* ~~~~~~~~~~~~~~~
-* DGSVJ1 applies few sweeps of Jacobi rotations in the column space of
-* the input M-by-N matrix A. The pivot pairs are taken from the (1,2)
-* off-diagonal block in the corresponding N-by-N Gram matrix A^T * A. The
-* block-entries (tiles) of the (1,2) off-diagonal block are marked by the
-* [x]'s in the following scheme:
-*
-* | * * * [x] [x] [x]|
-* | * * * [x] [x] [x]| Row-cycling in the nblr-by-nblc [x] blocks.
-* | * * * [x] [x] [x]| Row-cyclic pivoting inside each [x] block.
-* |[x] [x] [x] * * * |
-* |[x] [x] [x] * * * |
-* |[x] [x] [x] * * * |
-*
-* In terms of the columns of A, the first N1 columns are rotated 'against'
-* the remaining N-N1 columns, trying to increase the angle between the
-* corresponding subspaces. The off-diagonal block is N1-by(N-N1) and it is
-* tiled using quadratic tiles of side KBL. Here, KBL is a tunning parmeter.
-* The number of sweeps is given in NSWEEP and the orthogonality threshold
-* is given in TOL.
-*
-* Contributors
-* ~~~~~~~~~~~~
-* Zlatko Drmac (Zagreb, Croatia) and Kresimir Veselic (Hagen, Germany)
-*
-* Arguments
-* =========
-*
-* JOBV (input) CHARACTER*1
-* Specifies whether the output from this procedure is used
-* to compute the matrix V:
-* = 'V': the product of the Jacobi rotations is accumulated
-* by postmulyiplying the N-by-N array V.
-* (See the description of V.)
-* = 'A': the product of the Jacobi rotations is accumulated
-* by postmulyiplying the MV-by-N array V.
-* (See the descriptions of MV and V.)
-* = 'N': the Jacobi rotations are not accumulated.
-*
-* M (input) INTEGER
-* The number of rows of the input matrix A. M >= 0.
-*
-* N (input) INTEGER
-* The number of columns of the input matrix A.
-* M >= N >= 0.
-*
-* N1 (input) INTEGER
-* N1 specifies the 2 x 2 block partition, the first N1 columns are
-* rotated 'against' the remaining N-N1 columns of A.
-*
-* A (input/output) DOUBLE PRECISION array, dimension (LDA,N)
-* On entry, M-by-N matrix A, such that A*diag(D) represents
-* the input matrix.
-* On exit,
-* A_onexit * D_onexit represents the input matrix A*diag(D)
-* post-multiplied by a sequence of Jacobi rotations, where the
-* rotation threshold and the total number of sweeps are given in
-* TOL and NSWEEP, respectively.
-* (See the descriptions of N1, D, TOL and NSWEEP.)
-*
-* LDA (input) INTEGER
-* The leading dimension of the array A. LDA >= max(1,M).
-*
-* D (input/workspace/output) DOUBLE PRECISION array, dimension (N)
-* The array D accumulates the scaling factors from the fast scaled
-* Jacobi rotations.
-* On entry, A*diag(D) represents the input matrix.
-* On exit, A_onexit*diag(D_onexit) represents the input matrix
-* post-multiplied by a sequence of Jacobi rotations, where the
-* rotation threshold and the total number of sweeps are given in
-* TOL and NSWEEP, respectively.
-* (See the descriptions of N1, A, TOL and NSWEEP.)
-*
-* SVA (input/workspace/output) DOUBLE PRECISION array, dimension (N)
-* On entry, SVA contains the Euclidean norms of the columns of
-* the matrix A*diag(D).
-* On exit, SVA contains the Euclidean norms of the columns of
-* the matrix onexit*diag(D_onexit).
-*
-* MV (input) INTEGER
-* If JOBV .EQ. 'A', then MV rows of V are post-multipled by a
-* sequence of Jacobi rotations.
-* If JOBV = 'N', then MV is not referenced.
-*
-* V (input/output) DOUBLE PRECISION array, dimension (LDV,N)
-* If JOBV .EQ. 'V' then N rows of V are post-multipled by a
-* sequence of Jacobi rotations.
-* If JOBV .EQ. 'A' then MV rows of V are post-multipled by a
-* sequence of Jacobi rotations.
-* If JOBV = 'N', then V is not referenced.
-*
-* LDV (input) INTEGER
-* The leading dimension of the array V, LDV >= 1.
-* If JOBV = 'V', LDV .GE. N.
-* If JOBV = 'A', LDV .GE. MV.
-*
-* EPS (input) DOUBLE PRECISION
-* EPS = DLAMCH('Epsilon')
-*
-* SFMIN (input) DOUBLE PRECISION
-* SFMIN = DLAMCH('Safe Minimum')
-*
-* TOL (input) DOUBLE PRECISION
-* TOL is the threshold for Jacobi rotations. For a pair
-* A(:,p), A(:,q) of pivot columns, the Jacobi rotation is
-* applied only if DABS(COS(angle(A(:,p),A(:,q)))) .GT. TOL.
-*
-* NSWEEP (input) INTEGER
-* NSWEEP is the number of sweeps of Jacobi rotations to be
-* performed.
-*
-* WORK (workspace) DOUBLE PRECISION array, dimension (LWORK)
-*
-* LWORK (input) INTEGER
-* LWORK is the dimension of WORK. LWORK .GE. M.
-*
-* INFO (output) INTEGER
-* = 0 : successful exit.
-* < 0 : if INFO = -i, then the i-th argument had an illegal value
-*
* =====================================================================
*
* .. Local Parameters ..
- DOUBLE PRECISION ZERO, HALF, ONE, TWO
- PARAMETER ( ZERO = 0.0D0, HALF = 0.5D0, ONE = 1.0D0,
- $ TWO = 2.0D0 )
+ DOUBLE PRECISION ZERO, HALF, ONE
+ PARAMETER ( ZERO = 0.0D0, HALF = 0.5D0, ONE = 1.0D0 )
* ..
* .. Local Scalars ..
DOUBLE PRECISION AAPP, AAPP0, AAPQ, AAQQ, APOAQ, AQOAP, BIG,
@@ -178,7 +268,7 @@
DOUBLE PRECISION FASTR( 5 )
* ..
* .. Intrinsic Functions ..
- INTRINSIC DABS, DMAX1, DBLE, MIN0, DSIGN, DSQRT
+ INTRINSIC DABS, MAX, DBLE, MIN, DSIGN, DSQRT
* ..
* .. External Functions ..
DOUBLE PRECISION DDOT, DNRM2
@@ -187,7 +277,8 @@
EXTERNAL IDAMAX, LSAME, DDOT, DNRM2
* ..
* .. External Subroutines ..
- EXTERNAL DAXPY, DCOPY, DLASCL, DLASSQ, DROTM, DSWAP
+ EXTERNAL DAXPY, DCOPY, DLASCL, DLASSQ, DROTM, DSWAP,
+ $ XERBLA
* ..
* .. Executable Statements ..
*
@@ -207,7 +298,7 @@
INFO = -6
ELSE IF( ( RSVEC.OR.APPLV ) .AND. ( MV.LT.0 ) ) THEN
INFO = -9
- ELSE IF( ( RSVEC.AND.( LDV.LT.N ) ).OR.
+ ELSE IF( ( RSVEC.AND.( LDV.LT.N ) ).OR.
$ ( APPLV.AND.( LDV.LT.MV ) ) ) THEN
INFO = -11
ELSE IF( TOL.LE.EPS ) THEN
@@ -252,7 +343,7 @@
*
* .. Row-cyclic pivot strategy with de Rijk's pivoting ..
*
- KBL = MIN0( 8, N )
+ KBL = MIN( 8, N )
NBLR = N1 / KBL
IF( ( NBLR*KBL ).NE.N1 )NBLR = NBLR + 1
@@ -263,7 +354,7 @@
BLSKIP = ( KBL**2 ) + 1
*[TP] BLKSKIP is a tuning parameter that depends on SWBAND and KBL.
- ROWSKIP = MIN0( 5, KBL )
+ ROWSKIP = MIN( 5, KBL )
*[TP] ROWSKIP is a tuning parameter.
SWBAND = 0
*[TP] SWBAND is a tuning parameter. It is meaningful and effective
@@ -306,7 +397,7 @@
* doing the block at ( ibr, jbc )
IJBLSK = 0
- DO 2100 p = igl, MIN0( igl+KBL-1, N1 )
+ DO 2100 p = igl, MIN( igl+KBL-1, N1 )
AAPP = SVA( p )
@@ -314,7 +405,7 @@
PSKIPPED = 0
- DO 2200 q = jgl, MIN0( jgl+KBL-1, N )
+ DO 2200 q = jgl, MIN( jgl+KBL-1, N )
*
AAQQ = SVA( q )
@@ -361,7 +452,7 @@
END IF
END IF
- MXAAPQ = DMAX1( MXAAPQ, DABS( AAPQ ) )
+ MXAAPQ = MAX( MXAAPQ, DABS( AAPQ ) )
* TO rotate or NOT to rotate, THAT is the question ...
*
@@ -388,11 +479,11 @@
$ V( 1, p ), 1,
$ V( 1, q ), 1,
$ FASTR )
- SVA( q ) = AAQQ*DSQRT( DMAX1( ZERO,
+ SVA( q ) = AAQQ*DSQRT( MAX( ZERO,
$ ONE+T*APOAQ*AAPQ ) )
- AAPP = AAPP*DSQRT( DMAX1( ZERO,
+ AAPP = AAPP*DSQRT( MAX( ZERO,
$ ONE-T*AQOAP*AAPQ ) )
- MXSINJ = DMAX1( MXSINJ, DABS( T ) )
+ MXSINJ = MAX( MXSINJ, DABS( T ) )
ELSE
*
* .. choose correct signum for THETA and rotate
@@ -403,10 +494,10 @@
$ DSQRT( ONE+THETA*THETA ) )
CS = DSQRT( ONE / ( ONE+T*T ) )
SN = T*CS
- MXSINJ = DMAX1( MXSINJ, DABS( SN ) )
- SVA( q ) = AAQQ*DSQRT( DMAX1( ZERO,
+ MXSINJ = MAX( MXSINJ, DABS( SN ) )
+ SVA( q ) = AAQQ*DSQRT( MAX( ZERO,
$ ONE+T*APOAQ*AAPQ ) )
- AAPP = AAPP*DSQRT( DMAX1( ZERO,
+ AAPP = AAPP*DSQRT( MAX( ZERO,
$ ONE-T*AQOAP*AAPQ ) )
APOAQ = D( p ) / D( q )
@@ -521,9 +612,9 @@
CALL DLASCL( 'G', 0, 0, ONE, AAQQ,
$ M, 1, A( 1, q ), LDA,
$ IERR )
- SVA( q ) = AAQQ*DSQRT( DMAX1( ZERO,
+ SVA( q ) = AAQQ*DSQRT( MAX( ZERO,
$ ONE-AAPQ*AAPQ ) )
- MXSINJ = DMAX1( MXSINJ, SFMIN )
+ MXSINJ = MAX( MXSINJ, SFMIN )
ELSE
CALL DCOPY( M, A( 1, q ), 1, WORK,
$ 1 )
@@ -538,9 +629,9 @@
CALL DLASCL( 'G', 0, 0, ONE, AAPP,
$ M, 1, A( 1, p ), LDA,
$ IERR )
- SVA( p ) = AAPP*DSQRT( DMAX1( ZERO,
+ SVA( p ) = AAPP*DSQRT( MAX( ZERO,
$ ONE-AAPQ*AAPQ ) )
- MXSINJ = DMAX1( MXSINJ, SFMIN )
+ MXSINJ = MAX( MXSINJ, SFMIN )
END IF
END IF
* END IF ROTOK THEN ... ELSE
@@ -611,7 +702,7 @@
*
ELSE
IF( AAPP.EQ.ZERO )NOTROT = NOTROT +
- $ MIN0( jgl+KBL-1, N ) - jgl + 1
+ $ MIN( jgl+KBL-1, N ) - jgl + 1
IF( AAPP.LT.ZERO )NOTROT = 0
*** IF ( NOTROT .GE. EMPTSW ) GO TO 2011
END IF
@@ -622,7 +713,7 @@
* end of the jbc-loop
2011 CONTINUE
*2011 bailed out of the jbc-loop
- DO 2012 p = igl, MIN0( igl+KBL-1, N )
+ DO 2012 p = igl, MIN( igl+KBL-1, N )
SVA( p ) = DABS( SVA( p ) )
2012 CONTINUE
*** IF ( NOTROT .GE. EMPTSW ) GO TO 1994