1 *> \brief <b> SGELSS solves overdetermined or underdetermined systems for GE matrices</b>
3 * =========== DOCUMENTATION ===========
5 * Online html documentation available at
6 * http://www.netlib.org/lapack/explore-html/
9 *> Download SGELSS + dependencies
10 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/sgelss.f">
12 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/sgelss.f">
14 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/sgelss.f">
21 * SUBROUTINE SGELSS( M, N, NRHS, A, LDA, B, LDB, S, RCOND, RANK,
24 * .. Scalar Arguments ..
25 * INTEGER INFO, LDA, LDB, LWORK, M, N, NRHS, RANK
28 * .. Array Arguments ..
29 * REAL A( LDA, * ), B( LDB, * ), S( * ), WORK( * )
38 *> SGELSS computes the minimum norm solution to a real linear least
41 *> Minimize 2-norm(| b - A*x |).
43 *> using the singular value decomposition (SVD) of A. A is an M-by-N
44 *> matrix which may be rank-deficient.
46 *> Several right hand side vectors b and solution vectors x can be
47 *> handled in a single call; they are stored as the columns of the
48 *> M-by-NRHS right hand side matrix B and the N-by-NRHS solution matrix
51 *> The effective rank of A is determined by treating as zero those
52 *> singular values which are less than RCOND times the largest singular
62 *> The number of rows of the matrix A. M >= 0.
68 *> The number of columns of the matrix A. N >= 0.
74 *> The number of right hand sides, i.e., the number of columns
75 *> of the matrices B and X. NRHS >= 0.
80 *> A is REAL array, dimension (LDA,N)
81 *> On entry, the M-by-N matrix A.
82 *> On exit, the first min(m,n) rows of A are overwritten with
83 *> its right singular vectors, stored rowwise.
89 *> The leading dimension of the array A. LDA >= max(1,M).
94 *> B is REAL array, dimension (LDB,NRHS)
95 *> On entry, the M-by-NRHS right hand side matrix B.
96 *> On exit, B is overwritten by the N-by-NRHS solution
97 *> matrix X. If m >= n and RANK = n, the residual
98 *> sum-of-squares for the solution in the i-th column is given
99 *> by the sum of squares of elements n+1:m in that column.
105 *> The leading dimension of the array B. LDB >= max(1,max(M,N)).
110 *> S is REAL array, dimension (min(M,N))
111 *> The singular values of A in decreasing order.
112 *> The condition number of A in the 2-norm = S(1)/S(min(m,n)).
118 *> RCOND is used to determine the effective rank of A.
119 *> Singular values S(i) <= RCOND*S(1) are treated as zero.
120 *> If RCOND < 0, machine precision is used instead.
126 *> The effective rank of A, i.e., the number of singular values
127 *> which are greater than RCOND*S(1).
132 *> WORK is REAL array, dimension (MAX(1,LWORK))
133 *> On exit, if INFO = 0, WORK(1) returns the optimal LWORK.
139 *> The dimension of the array WORK. LWORK >= 1, and also:
140 *> LWORK >= 3*min(M,N) + max( 2*min(M,N), max(M,N), NRHS )
141 *> For good performance, LWORK should generally be larger.
143 *> If LWORK = -1, then a workspace query is assumed; the routine
144 *> only calculates the optimal size of the WORK array, returns
145 *> this value as the first entry of the WORK array, and no error
146 *> message related to LWORK is issued by XERBLA.
152 *> = 0: successful exit
153 *> < 0: if INFO = -i, the i-th argument had an illegal value.
154 *> > 0: the algorithm for computing the SVD failed to converge;
155 *> if INFO = i, i off-diagonal elements of an intermediate
156 *> bidiagonal form did not converge to zero.
162 *> \author Univ. of Tennessee
163 *> \author Univ. of California Berkeley
164 *> \author Univ. of Colorado Denver
167 *> \date December 2016
169 *> \ingroup realGEsolve
171 * =====================================================================
172 SUBROUTINE SGELSS( M, N, NRHS, A, LDA, B, LDB, S, RCOND, RANK,
173 $ WORK, LWORK, INFO )
175 * -- LAPACK driver routine (version 3.7.0) --
176 * -- LAPACK is a software package provided by Univ. of Tennessee, --
177 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
180 * .. Scalar Arguments ..
181 INTEGER INFO, LDA, LDB, LWORK, M, N, NRHS, RANK
184 * .. Array Arguments ..
185 REAL A( LDA, * ), B( LDB, * ), S( * ), WORK( * )
188 * =====================================================================
192 PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 )
194 * .. Local Scalars ..
196 INTEGER BDSPAC, BL, CHUNK, I, IASCL, IBSCL, IE, IL,
197 $ ITAU, ITAUP, ITAUQ, IWORK, LDWORK, MAXMN,
198 $ MAXWRK, MINMN, MINWRK, MM, MNTHR
199 INTEGER LWORK_SGEQRF, LWORK_SORMQR, LWORK_SGEBRD,
200 $ LWORK_SORMBR, LWORK_SORGBR, LWORK_SORMLQ
201 REAL ANRM, BIGNUM, BNRM, EPS, SFMIN, SMLNUM, THR
206 * .. External Subroutines ..
207 EXTERNAL SBDSQR, SCOPY, SGEBRD, SGELQF, SGEMM, SGEMV,
208 $ SGEQRF, SLABAD, SLACPY, SLASCL, SLASET, SORGBR,
209 $ SORMBR, SORMLQ, SORMQR, SRSCL, XERBLA
211 * .. External Functions ..
214 EXTERNAL ILAENV, SLAMCH, SLANGE
216 * .. Intrinsic Functions ..
219 * .. Executable Statements ..
221 * Test the input arguments
226 LQUERY = ( LWORK.EQ.-1 )
229 ELSE IF( N.LT.0 ) THEN
231 ELSE IF( NRHS.LT.0 ) THEN
233 ELSE IF( LDA.LT.MAX( 1, M ) ) THEN
235 ELSE IF( LDB.LT.MAX( 1, MAXMN ) ) THEN
240 * (Note: Comments in the code beginning "Workspace:" describe the
241 * minimal amount of workspace needed at that point in the code,
242 * as well as the preferred amount for good performance.
243 * NB refers to the optimal block size for the immediately
244 * following subroutine, as returned by ILAENV.)
249 IF( MINMN.GT.0 ) THEN
251 MNTHR = ILAENV( 6, 'SGELSS', ' ', M, N, NRHS, -1 )
252 IF( M.GE.N .AND. M.GE.MNTHR ) THEN
254 * Path 1a - overdetermined, with many more rows than
257 * Compute space needed for SGEQRF
258 CALL SGEQRF( M, N, A, LDA, DUM(1), DUM(1), -1, INFO )
260 * Compute space needed for SORMQR
261 CALL SORMQR( 'L', 'T', M, NRHS, N, A, LDA, DUM(1), B,
262 $ LDB, DUM(1), -1, INFO )
265 MAXWRK = MAX( MAXWRK, N + LWORK_SGEQRF )
266 MAXWRK = MAX( MAXWRK, N + LWORK_SORMQR )
270 * Path 1 - overdetermined or exactly determined
272 * Compute workspace needed for SBDSQR
274 BDSPAC = MAX( 1, 5*N )
275 * Compute space needed for SGEBRD
276 CALL SGEBRD( MM, N, A, LDA, S, DUM(1), DUM(1),
277 $ DUM(1), DUM(1), -1, INFO )
279 * Compute space needed for SORMBR
280 CALL SORMBR( 'Q', 'L', 'T', MM, NRHS, N, A, LDA, DUM(1),
281 $ B, LDB, DUM(1), -1, INFO )
283 * Compute space needed for SORGBR
284 CALL SORGBR( 'P', N, N, N, A, LDA, DUM(1),
287 * Compute total workspace needed
288 MAXWRK = MAX( MAXWRK, 3*N + LWORK_SGEBRD )
289 MAXWRK = MAX( MAXWRK, 3*N + LWORK_SORMBR )
290 MAXWRK = MAX( MAXWRK, 3*N + LWORK_SORGBR )
291 MAXWRK = MAX( MAXWRK, BDSPAC )
292 MAXWRK = MAX( MAXWRK, N*NRHS )
293 MINWRK = MAX( 3*N + MM, 3*N + NRHS, BDSPAC )
294 MAXWRK = MAX( MINWRK, MAXWRK )
298 * Compute workspace needed for SBDSQR
300 BDSPAC = MAX( 1, 5*M )
301 MINWRK = MAX( 3*M+NRHS, 3*M+N, BDSPAC )
302 IF( N.GE.MNTHR ) THEN
304 * Path 2a - underdetermined, with many more columns
307 * Compute space needed for SGEBRD
308 CALL SGEBRD( M, M, A, LDA, S, DUM(1), DUM(1),
309 $ DUM(1), DUM(1), -1, INFO )
311 * Compute space needed for SORMBR
312 CALL SORMBR( 'Q', 'L', 'T', M, NRHS, N, A, LDA,
313 $ DUM(1), B, LDB, DUM(1), -1, INFO )
315 * Compute space needed for SORGBR
316 CALL SORGBR( 'P', M, M, M, A, LDA, DUM(1),
319 * Compute space needed for SORMLQ
320 CALL SORMLQ( 'L', 'T', N, NRHS, M, A, LDA, DUM(1),
321 $ B, LDB, DUM(1), -1, INFO )
323 * Compute total workspace needed
324 MAXWRK = M + M*ILAENV( 1, 'SGELQF', ' ', M, N, -1,
326 MAXWRK = MAX( MAXWRK, M*M + 4*M + LWORK_SGEBRD )
327 MAXWRK = MAX( MAXWRK, M*M + 4*M + LWORK_SORMBR )
328 MAXWRK = MAX( MAXWRK, M*M + 4*M + LWORK_SORGBR )
329 MAXWRK = MAX( MAXWRK, M*M + M + BDSPAC )
331 MAXWRK = MAX( MAXWRK, M*M + M + M*NRHS )
333 MAXWRK = MAX( MAXWRK, M*M + 2*M )
335 MAXWRK = MAX( MAXWRK, M + LWORK_SORMLQ )
338 * Path 2 - underdetermined
340 * Compute space needed for SGEBRD
341 CALL SGEBRD( M, N, A, LDA, S, DUM(1), DUM(1),
342 $ DUM(1), DUM(1), -1, INFO )
344 * Compute space needed for SORMBR
345 CALL SORMBR( 'Q', 'L', 'T', M, NRHS, M, A, LDA,
346 $ DUM(1), B, LDB, DUM(1), -1, INFO )
348 * Compute space needed for SORGBR
349 CALL SORGBR( 'P', M, N, M, A, LDA, DUM(1),
352 MAXWRK = 3*M + LWORK_SGEBRD
353 MAXWRK = MAX( MAXWRK, 3*M + LWORK_SORMBR )
354 MAXWRK = MAX( MAXWRK, 3*M + LWORK_SORGBR )
355 MAXWRK = MAX( MAXWRK, BDSPAC )
356 MAXWRK = MAX( MAXWRK, N*NRHS )
359 MAXWRK = MAX( MINWRK, MAXWRK )
363 IF( LWORK.LT.MINWRK .AND. .NOT.LQUERY )
368 CALL XERBLA( 'SGELSS', -INFO )
370 ELSE IF( LQUERY ) THEN
374 * Quick return if possible
376 IF( M.EQ.0 .OR. N.EQ.0 ) THEN
381 * Get machine parameters
384 SFMIN = SLAMCH( 'S' )
386 BIGNUM = ONE / SMLNUM
387 CALL SLABAD( SMLNUM, BIGNUM )
389 * Scale A if max element outside range [SMLNUM,BIGNUM]
391 ANRM = SLANGE( 'M', M, N, A, LDA, WORK )
393 IF( ANRM.GT.ZERO .AND. ANRM.LT.SMLNUM ) THEN
395 * Scale matrix norm up to SMLNUM
397 CALL SLASCL( 'G', 0, 0, ANRM, SMLNUM, M, N, A, LDA, INFO )
399 ELSE IF( ANRM.GT.BIGNUM ) THEN
401 * Scale matrix norm down to BIGNUM
403 CALL SLASCL( 'G', 0, 0, ANRM, BIGNUM, M, N, A, LDA, INFO )
405 ELSE IF( ANRM.EQ.ZERO ) THEN
407 * Matrix all zero. Return zero solution.
409 CALL SLASET( 'F', MAX( M, N ), NRHS, ZERO, ZERO, B, LDB )
410 CALL SLASET( 'F', MINMN, 1, ZERO, ZERO, S, MINMN )
415 * Scale B if max element outside range [SMLNUM,BIGNUM]
417 BNRM = SLANGE( 'M', M, NRHS, B, LDB, WORK )
419 IF( BNRM.GT.ZERO .AND. BNRM.LT.SMLNUM ) THEN
421 * Scale matrix norm up to SMLNUM
423 CALL SLASCL( 'G', 0, 0, BNRM, SMLNUM, M, NRHS, B, LDB, INFO )
425 ELSE IF( BNRM.GT.BIGNUM ) THEN
427 * Scale matrix norm down to BIGNUM
429 CALL SLASCL( 'G', 0, 0, BNRM, BIGNUM, M, NRHS, B, LDB, INFO )
433 * Overdetermined case
437 * Path 1 - overdetermined or exactly determined
440 IF( M.GE.MNTHR ) THEN
442 * Path 1a - overdetermined, with many more rows than columns
449 * (Workspace: need 2*N, prefer N+N*NB)
451 CALL SGEQRF( M, N, A, LDA, WORK( ITAU ), WORK( IWORK ),
452 $ LWORK-IWORK+1, INFO )
454 * Multiply B by transpose(Q)
455 * (Workspace: need N+NRHS, prefer N+NRHS*NB)
457 CALL SORMQR( 'L', 'T', M, NRHS, N, A, LDA, WORK( ITAU ), B,
458 $ LDB, WORK( IWORK ), LWORK-IWORK+1, INFO )
463 $ CALL SLASET( 'L', N-1, N-1, ZERO, ZERO, A( 2, 1 ), LDA )
471 * Bidiagonalize R in A
472 * (Workspace: need 3*N+MM, prefer 3*N+(MM+N)*NB)
474 CALL SGEBRD( MM, N, A, LDA, S, WORK( IE ), WORK( ITAUQ ),
475 $ WORK( ITAUP ), WORK( IWORK ), LWORK-IWORK+1,
478 * Multiply B by transpose of left bidiagonalizing vectors of R
479 * (Workspace: need 3*N+NRHS, prefer 3*N+NRHS*NB)
481 CALL SORMBR( 'Q', 'L', 'T', MM, NRHS, N, A, LDA, WORK( ITAUQ ),
482 $ B, LDB, WORK( IWORK ), LWORK-IWORK+1, INFO )
484 * Generate right bidiagonalizing vectors of R in A
485 * (Workspace: need 4*N-1, prefer 3*N+(N-1)*NB)
487 CALL SORGBR( 'P', N, N, N, A, LDA, WORK( ITAUP ),
488 $ WORK( IWORK ), LWORK-IWORK+1, INFO )
491 * Perform bidiagonal QR iteration
492 * multiply B by transpose of left singular vectors
493 * compute right singular vectors in A
494 * (Workspace: need BDSPAC)
496 CALL SBDSQR( 'U', N, N, 0, NRHS, S, WORK( IE ), A, LDA, DUM,
497 $ 1, B, LDB, WORK( IWORK ), INFO )
501 * Multiply B by reciprocals of singular values
503 THR = MAX( RCOND*S( 1 ), SFMIN )
505 $ THR = MAX( EPS*S( 1 ), SFMIN )
508 IF( S( I ).GT.THR ) THEN
509 CALL SRSCL( NRHS, S( I ), B( I, 1 ), LDB )
512 CALL SLASET( 'F', 1, NRHS, ZERO, ZERO, B( I, 1 ), LDB )
516 * Multiply B by right singular vectors
517 * (Workspace: need N, prefer N*NRHS)
519 IF( LWORK.GE.LDB*NRHS .AND. NRHS.GT.1 ) THEN
520 CALL SGEMM( 'T', 'N', N, NRHS, N, ONE, A, LDA, B, LDB, ZERO,
522 CALL SLACPY( 'G', N, NRHS, WORK, LDB, B, LDB )
523 ELSE IF( NRHS.GT.1 ) THEN
525 DO 20 I = 1, NRHS, CHUNK
526 BL = MIN( NRHS-I+1, CHUNK )
527 CALL SGEMM( 'T', 'N', N, BL, N, ONE, A, LDA, B( 1, I ),
528 $ LDB, ZERO, WORK, N )
529 CALL SLACPY( 'G', N, BL, WORK, N, B( 1, I ), LDB )
532 CALL SGEMV( 'T', N, N, ONE, A, LDA, B, 1, ZERO, WORK, 1 )
533 CALL SCOPY( N, WORK, 1, B, 1 )
536 ELSE IF( N.GE.MNTHR .AND. LWORK.GE.4*M+M*M+
537 $ MAX( M, 2*M-4, NRHS, N-3*M ) ) THEN
539 * Path 2a - underdetermined, with many more columns than rows
540 * and sufficient workspace for an efficient algorithm
543 IF( LWORK.GE.MAX( 4*M+M*LDA+MAX( M, 2*M-4, NRHS, N-3*M ),
544 $ M*LDA+M+M*NRHS ) )LDWORK = LDA
549 * (Workspace: need 2*M, prefer M+M*NB)
551 CALL SGELQF( M, N, A, LDA, WORK( ITAU ), WORK( IWORK ),
552 $ LWORK-IWORK+1, INFO )
555 * Copy L to WORK(IL), zeroing out above it
557 CALL SLACPY( 'L', M, M, A, LDA, WORK( IL ), LDWORK )
558 CALL SLASET( 'U', M-1, M-1, ZERO, ZERO, WORK( IL+LDWORK ),
565 * Bidiagonalize L in WORK(IL)
566 * (Workspace: need M*M+5*M, prefer M*M+4*M+2*M*NB)
568 CALL SGEBRD( M, M, WORK( IL ), LDWORK, S, WORK( IE ),
569 $ WORK( ITAUQ ), WORK( ITAUP ), WORK( IWORK ),
570 $ LWORK-IWORK+1, INFO )
572 * Multiply B by transpose of left bidiagonalizing vectors of L
573 * (Workspace: need M*M+4*M+NRHS, prefer M*M+4*M+NRHS*NB)
575 CALL SORMBR( 'Q', 'L', 'T', M, NRHS, M, WORK( IL ), LDWORK,
576 $ WORK( ITAUQ ), B, LDB, WORK( IWORK ),
577 $ LWORK-IWORK+1, INFO )
579 * Generate right bidiagonalizing vectors of R in WORK(IL)
580 * (Workspace: need M*M+5*M-1, prefer M*M+4*M+(M-1)*NB)
582 CALL SORGBR( 'P', M, M, M, WORK( IL ), LDWORK, WORK( ITAUP ),
583 $ WORK( IWORK ), LWORK-IWORK+1, INFO )
586 * Perform bidiagonal QR iteration,
587 * computing right singular vectors of L in WORK(IL) and
588 * multiplying B by transpose of left singular vectors
589 * (Workspace: need M*M+M+BDSPAC)
591 CALL SBDSQR( 'U', M, M, 0, NRHS, S, WORK( IE ), WORK( IL ),
592 $ LDWORK, A, LDA, B, LDB, WORK( IWORK ), INFO )
596 * Multiply B by reciprocals of singular values
598 THR = MAX( RCOND*S( 1 ), SFMIN )
600 $ THR = MAX( EPS*S( 1 ), SFMIN )
603 IF( S( I ).GT.THR ) THEN
604 CALL SRSCL( NRHS, S( I ), B( I, 1 ), LDB )
607 CALL SLASET( 'F', 1, NRHS, ZERO, ZERO, B( I, 1 ), LDB )
612 * Multiply B by right singular vectors of L in WORK(IL)
613 * (Workspace: need M*M+2*M, prefer M*M+M+M*NRHS)
615 IF( LWORK.GE.LDB*NRHS+IWORK-1 .AND. NRHS.GT.1 ) THEN
616 CALL SGEMM( 'T', 'N', M, NRHS, M, ONE, WORK( IL ), LDWORK,
617 $ B, LDB, ZERO, WORK( IWORK ), LDB )
618 CALL SLACPY( 'G', M, NRHS, WORK( IWORK ), LDB, B, LDB )
619 ELSE IF( NRHS.GT.1 ) THEN
620 CHUNK = ( LWORK-IWORK+1 ) / M
621 DO 40 I = 1, NRHS, CHUNK
622 BL = MIN( NRHS-I+1, CHUNK )
623 CALL SGEMM( 'T', 'N', M, BL, M, ONE, WORK( IL ), LDWORK,
624 $ B( 1, I ), LDB, ZERO, WORK( IWORK ), M )
625 CALL SLACPY( 'G', M, BL, WORK( IWORK ), M, B( 1, I ),
629 CALL SGEMV( 'T', M, M, ONE, WORK( IL ), LDWORK, B( 1, 1 ),
630 $ 1, ZERO, WORK( IWORK ), 1 )
631 CALL SCOPY( M, WORK( IWORK ), 1, B( 1, 1 ), 1 )
634 * Zero out below first M rows of B
636 CALL SLASET( 'F', N-M, NRHS, ZERO, ZERO, B( M+1, 1 ), LDB )
639 * Multiply transpose(Q) by B
640 * (Workspace: need M+NRHS, prefer M+NRHS*NB)
642 CALL SORMLQ( 'L', 'T', N, NRHS, M, A, LDA, WORK( ITAU ), B,
643 $ LDB, WORK( IWORK ), LWORK-IWORK+1, INFO )
647 * Path 2 - remaining underdetermined cases
655 * (Workspace: need 3*M+N, prefer 3*M+(M+N)*NB)
657 CALL SGEBRD( M, N, A, LDA, S, WORK( IE ), WORK( ITAUQ ),
658 $ WORK( ITAUP ), WORK( IWORK ), LWORK-IWORK+1,
661 * Multiply B by transpose of left bidiagonalizing vectors
662 * (Workspace: need 3*M+NRHS, prefer 3*M+NRHS*NB)
664 CALL SORMBR( 'Q', 'L', 'T', M, NRHS, N, A, LDA, WORK( ITAUQ ),
665 $ B, LDB, WORK( IWORK ), LWORK-IWORK+1, INFO )
667 * Generate right bidiagonalizing vectors in A
668 * (Workspace: need 4*M, prefer 3*M+M*NB)
670 CALL SORGBR( 'P', M, N, M, A, LDA, WORK( ITAUP ),
671 $ WORK( IWORK ), LWORK-IWORK+1, INFO )
674 * Perform bidiagonal QR iteration,
675 * computing right singular vectors of A in A and
676 * multiplying B by transpose of left singular vectors
677 * (Workspace: need BDSPAC)
679 CALL SBDSQR( 'L', M, N, 0, NRHS, S, WORK( IE ), A, LDA, DUM,
680 $ 1, B, LDB, WORK( IWORK ), INFO )
684 * Multiply B by reciprocals of singular values
686 THR = MAX( RCOND*S( 1 ), SFMIN )
688 $ THR = MAX( EPS*S( 1 ), SFMIN )
691 IF( S( I ).GT.THR ) THEN
692 CALL SRSCL( NRHS, S( I ), B( I, 1 ), LDB )
695 CALL SLASET( 'F', 1, NRHS, ZERO, ZERO, B( I, 1 ), LDB )
699 * Multiply B by right singular vectors of A
700 * (Workspace: need N, prefer N*NRHS)
702 IF( LWORK.GE.LDB*NRHS .AND. NRHS.GT.1 ) THEN
703 CALL SGEMM( 'T', 'N', N, NRHS, M, ONE, A, LDA, B, LDB, ZERO,
705 CALL SLACPY( 'F', N, NRHS, WORK, LDB, B, LDB )
706 ELSE IF( NRHS.GT.1 ) THEN
708 DO 60 I = 1, NRHS, CHUNK
709 BL = MIN( NRHS-I+1, CHUNK )
710 CALL SGEMM( 'T', 'N', N, BL, M, ONE, A, LDA, B( 1, I ),
711 $ LDB, ZERO, WORK, N )
712 CALL SLACPY( 'F', N, BL, WORK, N, B( 1, I ), LDB )
715 CALL SGEMV( 'T', M, N, ONE, A, LDA, B, 1, ZERO, WORK, 1 )
716 CALL SCOPY( N, WORK, 1, B, 1 )
722 IF( IASCL.EQ.1 ) THEN
723 CALL SLASCL( 'G', 0, 0, ANRM, SMLNUM, N, NRHS, B, LDB, INFO )
724 CALL SLASCL( 'G', 0, 0, SMLNUM, ANRM, MINMN, 1, S, MINMN,
726 ELSE IF( IASCL.EQ.2 ) THEN
727 CALL SLASCL( 'G', 0, 0, ANRM, BIGNUM, N, NRHS, B, LDB, INFO )
728 CALL SLASCL( 'G', 0, 0, BIGNUM, ANRM, MINMN, 1, S, MINMN,
731 IF( IBSCL.EQ.1 ) THEN
732 CALL SLASCL( 'G', 0, 0, SMLNUM, BNRM, N, NRHS, B, LDB, INFO )
733 ELSE IF( IBSCL.EQ.2 ) THEN
734 CALL SLASCL( 'G', 0, 0, BIGNUM, BNRM, N, NRHS, B, LDB, INFO )