LAPACK  3.10.1
LAPACK: Linear Algebra PACKage
ddrvgbx.f
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1 *> \brief \b DDRVGBX
2 *
3 * =========== DOCUMENTATION ===========
4 *
5 * Online html documentation available at
6 * http://www.netlib.org/lapack/explore-html/
7 *
8 * Definition:
9 * ===========
10 *
11 * SUBROUTINE DDRVGB( DOTYPE, NN, NVAL, NRHS, THRESH, TSTERR, A, LA,
12 * AFB, LAFB, ASAV, B, BSAV, X, XACT, S, WORK,
13 * RWORK, IWORK, NOUT )
14 *
15 * .. Scalar Arguments ..
16 * LOGICAL TSTERR
17 * INTEGER LA, LAFB, NN, NOUT, NRHS
18 * DOUBLE PRECISION THRESH
19 * ..
20 * .. Array Arguments ..
21 * LOGICAL DOTYPE( * )
22 * INTEGER IWORK( * ), NVAL( * )
23 * DOUBLE PRECISION A( * ), AFB( * ), ASAV( * ), B( * ), BSAV( * ),
24 * $ RWORK( * ), S( * ), WORK( * ), X( * ),
25 * $ XACT( * )
26 * ..
27 *
28 *
29 *> \par Purpose:
30 * =============
31 *>
32 *> \verbatim
33 *>
34 *> DDRVGB tests the driver routines DGBSV, -SVX, and -SVXX.
35 *>
36 *> Note that this file is used only when the XBLAS are available,
37 *> otherwise ddrvgb.f defines this subroutine.
38 *> \endverbatim
39 *
40 * Arguments:
41 * ==========
42 *
43 *> \param[in] DOTYPE
44 *> \verbatim
45 *> DOTYPE is LOGICAL array, dimension (NTYPES)
46 *> The matrix types to be used for testing. Matrices of type j
47 *> (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) =
48 *> .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used.
49 *> \endverbatim
50 *>
51 *> \param[in] NN
52 *> \verbatim
53 *> NN is INTEGER
54 *> The number of values of N contained in the vector NVAL.
55 *> \endverbatim
56 *>
57 *> \param[in] NVAL
58 *> \verbatim
59 *> NVAL is INTEGER array, dimension (NN)
60 *> The values of the matrix column dimension N.
61 *> \endverbatim
62 *>
63 *> \param[in] NRHS
64 *> \verbatim
65 *> NRHS is INTEGER
66 *> The number of right hand side vectors to be generated for
67 *> each linear system.
68 *> \endverbatim
69 *>
70 *> \param[in] THRESH
71 *> \verbatim
72 *> THRESH is DOUBLE PRECISION
73 *> The threshold value for the test ratios. A result is
74 *> included in the output file if RESULT >= THRESH. To have
75 *> every test ratio printed, use THRESH = 0.
76 *> \endverbatim
77 *>
78 *> \param[in] TSTERR
79 *> \verbatim
80 *> TSTERR is LOGICAL
81 *> Flag that indicates whether error exits are to be tested.
82 *> \endverbatim
83 *>
84 *> \param[out] A
85 *> \verbatim
86 *> A is DOUBLE PRECISION array, dimension (LA)
87 *> \endverbatim
88 *>
89 *> \param[in] LA
90 *> \verbatim
91 *> LA is INTEGER
92 *> The length of the array A. LA >= (2*NMAX-1)*NMAX
93 *> where NMAX is the largest entry in NVAL.
94 *> \endverbatim
95 *>
96 *> \param[out] AFB
97 *> \verbatim
98 *> AFB is DOUBLE PRECISION array, dimension (LAFB)
99 *> \endverbatim
100 *>
101 *> \param[in] LAFB
102 *> \verbatim
103 *> LAFB is INTEGER
104 *> The length of the array AFB. LAFB >= (3*NMAX-2)*NMAX
105 *> where NMAX is the largest entry in NVAL.
106 *> \endverbatim
107 *>
108 *> \param[out] ASAV
109 *> \verbatim
110 *> ASAV is DOUBLE PRECISION array, dimension (LA)
111 *> \endverbatim
112 *>
113 *> \param[out] B
114 *> \verbatim
115 *> B is DOUBLE PRECISION array, dimension (NMAX*NRHS)
116 *> \endverbatim
117 *>
118 *> \param[out] BSAV
119 *> \verbatim
120 *> BSAV is DOUBLE PRECISION array, dimension (NMAX*NRHS)
121 *> \endverbatim
122 *>
123 *> \param[out] X
124 *> \verbatim
125 *> X is DOUBLE PRECISION array, dimension (NMAX*NRHS)
126 *> \endverbatim
127 *>
128 *> \param[out] XACT
129 *> \verbatim
130 *> XACT is DOUBLE PRECISION array, dimension (NMAX*NRHS)
131 *> \endverbatim
132 *>
133 *> \param[out] S
134 *> \verbatim
135 *> S is DOUBLE PRECISION array, dimension (2*NMAX)
136 *> \endverbatim
137 *>
138 *> \param[out] WORK
139 *> \verbatim
140 *> WORK is DOUBLE PRECISION array, dimension
141 *> (NMAX*max(3,NRHS,NMAX))
142 *> \endverbatim
143 *>
144 *> \param[out] RWORK
145 *> \verbatim
146 *> RWORK is DOUBLE PRECISION array, dimension
147 *> (max(2*NMAX,NMAX+2*NRHS))
148 *> \endverbatim
149 *>
150 *> \param[out] IWORK
151 *> \verbatim
152 *> IWORK is INTEGER array, dimension (2*NMAX)
153 *> \endverbatim
154 *>
155 *> \param[in] NOUT
156 *> \verbatim
157 *> NOUT is INTEGER
158 *> The unit number for output.
159 *> \endverbatim
160 *
161 * Authors:
162 * ========
163 *
164 *> \author Univ. of Tennessee
165 *> \author Univ. of California Berkeley
166 *> \author Univ. of Colorado Denver
167 *> \author NAG Ltd.
168 *
169 *> \ingroup double_lin
170 *
171 * =====================================================================
172  SUBROUTINE ddrvgb( DOTYPE, NN, NVAL, NRHS, THRESH, TSTERR, A, LA,
173  $ AFB, LAFB, ASAV, B, BSAV, X, XACT, S, WORK,
174  $ RWORK, IWORK, NOUT )
175 *
176 * -- LAPACK test routine --
177 * -- LAPACK is a software package provided by Univ. of Tennessee, --
178 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
179 *
180 * .. Scalar Arguments ..
181  LOGICAL TSTERR
182  INTEGER LA, LAFB, NN, NOUT, NRHS
183  DOUBLE PRECISION THRESH
184 * ..
185 * .. Array Arguments ..
186  LOGICAL DOTYPE( * )
187  INTEGER IWORK( * ), NVAL( * )
188  DOUBLE PRECISION A( * ), AFB( * ), ASAV( * ), B( * ), BSAV( * ),
189  $ rwork( * ), s( * ), work( * ), x( * ),
190  $ xact( * )
191 * ..
192 *
193 * =====================================================================
194 *
195 * .. Parameters ..
196  DOUBLE PRECISION ONE, ZERO
197  PARAMETER ( ONE = 1.0d+0, zero = 0.0d+0 )
198  INTEGER NTYPES
199  parameter( ntypes = 8 )
200  INTEGER NTESTS
201  parameter( ntests = 7 )
202  INTEGER NTRAN
203  parameter( ntran = 3 )
204 * ..
205 * .. Local Scalars ..
206  LOGICAL EQUIL, NOFACT, PREFAC, TRFCON, ZEROT
207  CHARACTER DIST, EQUED, FACT, TRANS, TYPE, XTYPE
208  CHARACTER*3 PATH
209  INTEGER I, I1, I2, IEQUED, IFACT, IKL, IKU, IMAT, IN,
210  $ info, ioff, itran, izero, j, k, k1, kl, ku,
211  $ lda, ldafb, ldb, mode, n, nb, nbmin, nerrs,
212  $ nfact, nfail, nimat, nkl, nku, nrun, nt,
213  $ n_err_bnds
214  DOUBLE PRECISION AINVNM, AMAX, ANORM, ANORMI, ANORMO, ANRMPV,
215  $ CNDNUM, COLCND, RCOND, RCONDC, RCONDI, RCONDO,
216  $ roldc, roldi, roldo, rowcnd, rpvgrw,
217  $ rpvgrw_svxx
218 * ..
219 * .. Local Arrays ..
220  CHARACTER EQUEDS( 4 ), FACTS( 3 ), TRANSS( NTRAN )
221  INTEGER ISEED( 4 ), ISEEDY( 4 )
222  DOUBLE PRECISION RESULT( NTESTS ), BERR( NRHS ),
223  $ errbnds_n( nrhs, 3 ), errbnds_c( nrhs, 3 )
224 * ..
225 * .. External Functions ..
226  LOGICAL LSAME
227  DOUBLE PRECISION DGET06, DLAMCH, DLANGB, DLANGE, DLANTB,
228  $ dla_gbrpvgrw
229  EXTERNAL lsame, dget06, dlamch, dlangb, dlange, dlantb,
230  $ dla_gbrpvgrw
231 * ..
232 * .. External Subroutines ..
233  EXTERNAL aladhd, alaerh, alasvm, derrvx, dgbequ, dgbsv,
234  $ dgbsvx, dgbt01, dgbt02, dgbt05, dgbtrf, dgbtrs,
235  $ dget04, dlacpy, dlaqgb, dlarhs, dlaset, dlatb4,
236  $ dlatms, xlaenv, dgbsvxx, dgbequb
237 * ..
238 * .. Intrinsic Functions ..
239  INTRINSIC abs, max, min
240 * ..
241 * .. Scalars in Common ..
242  LOGICAL LERR, OK
243  CHARACTER*32 SRNAMT
244  INTEGER INFOT, NUNIT
245 * ..
246 * .. Common blocks ..
247  COMMON / infoc / infot, nunit, ok, lerr
248  COMMON / srnamc / srnamt
249 * ..
250 * .. Data statements ..
251  DATA iseedy / 1988, 1989, 1990, 1991 /
252  DATA transs / 'N', 'T', 'C' /
253  DATA facts / 'F', 'N', 'E' /
254  DATA equeds / 'N', 'R', 'C', 'B' /
255 * ..
256 * .. Executable Statements ..
257 *
258 * Initialize constants and the random number seed.
259 *
260  path( 1: 1 ) = 'Double precision'
261  path( 2: 3 ) = 'GB'
262  nrun = 0
263  nfail = 0
264  nerrs = 0
265  DO 10 i = 1, 4
266  iseed( i ) = iseedy( i )
267  10 CONTINUE
268 *
269 * Test the error exits
270 *
271  IF( tsterr )
272  $ CALL derrvx( path, nout )
273  infot = 0
274 *
275 * Set the block size and minimum block size for testing.
276 *
277  nb = 1
278  nbmin = 2
279  CALL xlaenv( 1, nb )
280  CALL xlaenv( 2, nbmin )
281 *
282 * Do for each value of N in NVAL
283 *
284  DO 150 in = 1, nn
285  n = nval( in )
286  ldb = max( n, 1 )
287  xtype = 'N'
288 *
289 * Set limits on the number of loop iterations.
290 *
291  nkl = max( 1, min( n, 4 ) )
292  IF( n.EQ.0 )
293  $ nkl = 1
294  nku = nkl
295  nimat = ntypes
296  IF( n.LE.0 )
297  $ nimat = 1
298 *
299  DO 140 ikl = 1, nkl
300 *
301 * Do for KL = 0, N-1, (3N-1)/4, and (N+1)/4. This order makes
302 * it easier to skip redundant values for small values of N.
303 *
304  IF( ikl.EQ.1 ) THEN
305  kl = 0
306  ELSE IF( ikl.EQ.2 ) THEN
307  kl = max( n-1, 0 )
308  ELSE IF( ikl.EQ.3 ) THEN
309  kl = ( 3*n-1 ) / 4
310  ELSE IF( ikl.EQ.4 ) THEN
311  kl = ( n+1 ) / 4
312  END IF
313  DO 130 iku = 1, nku
314 *
315 * Do for KU = 0, N-1, (3N-1)/4, and (N+1)/4. This order
316 * makes it easier to skip redundant values for small
317 * values of N.
318 *
319  IF( iku.EQ.1 ) THEN
320  ku = 0
321  ELSE IF( iku.EQ.2 ) THEN
322  ku = max( n-1, 0 )
323  ELSE IF( iku.EQ.3 ) THEN
324  ku = ( 3*n-1 ) / 4
325  ELSE IF( iku.EQ.4 ) THEN
326  ku = ( n+1 ) / 4
327  END IF
328 *
329 * Check that A and AFB are big enough to generate this
330 * matrix.
331 *
332  lda = kl + ku + 1
333  ldafb = 2*kl + ku + 1
334  IF( lda*n.GT.la .OR. ldafb*n.GT.lafb ) THEN
335  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
336  $ CALL aladhd( nout, path )
337  IF( lda*n.GT.la ) THEN
338  WRITE( nout, fmt = 9999 )la, n, kl, ku,
339  $ n*( kl+ku+1 )
340  nerrs = nerrs + 1
341  END IF
342  IF( ldafb*n.GT.lafb ) THEN
343  WRITE( nout, fmt = 9998 )lafb, n, kl, ku,
344  $ n*( 2*kl+ku+1 )
345  nerrs = nerrs + 1
346  END IF
347  GO TO 130
348  END IF
349 *
350  DO 120 imat = 1, nimat
351 *
352 * Do the tests only if DOTYPE( IMAT ) is true.
353 *
354  IF( .NOT.dotype( imat ) )
355  $ GO TO 120
356 *
357 * Skip types 2, 3, or 4 if the matrix is too small.
358 *
359  zerot = imat.GE.2 .AND. imat.LE.4
360  IF( zerot .AND. n.LT.imat-1 )
361  $ GO TO 120
362 *
363 * Set up parameters with DLATB4 and generate a
364 * test matrix with DLATMS.
365 *
366  CALL dlatb4( path, imat, n, n, TYPE, KL, KU, ANORM,
367  $ MODE, CNDNUM, DIST )
368  rcondc = one / cndnum
369 *
370  srnamt = 'DLATMS'
371  CALL dlatms( n, n, dist, iseed, TYPE, RWORK, MODE,
372  $ cndnum, anorm, kl, ku, 'Z', a, lda, work,
373  $ info )
374 *
375 * Check the error code from DLATMS.
376 *
377  IF( info.NE.0 ) THEN
378  CALL alaerh( path, 'DLATMS', info, 0, ' ', n, n,
379  $ kl, ku, -1, imat, nfail, nerrs, nout )
380  GO TO 120
381  END IF
382 *
383 * For types 2, 3, and 4, zero one or more columns of
384 * the matrix to test that INFO is returned correctly.
385 *
386  izero = 0
387  IF( zerot ) THEN
388  IF( imat.EQ.2 ) THEN
389  izero = 1
390  ELSE IF( imat.EQ.3 ) THEN
391  izero = n
392  ELSE
393  izero = n / 2 + 1
394  END IF
395  ioff = ( izero-1 )*lda
396  IF( imat.LT.4 ) THEN
397  i1 = max( 1, ku+2-izero )
398  i2 = min( kl+ku+1, ku+1+( n-izero ) )
399  DO 20 i = i1, i2
400  a( ioff+i ) = zero
401  20 CONTINUE
402  ELSE
403  DO 40 j = izero, n
404  DO 30 i = max( 1, ku+2-j ),
405  $ min( kl+ku+1, ku+1+( n-j ) )
406  a( ioff+i ) = zero
407  30 CONTINUE
408  ioff = ioff + lda
409  40 CONTINUE
410  END IF
411  END IF
412 *
413 * Save a copy of the matrix A in ASAV.
414 *
415  CALL dlacpy( 'Full', kl+ku+1, n, a, lda, asav, lda )
416 *
417  DO 110 iequed = 1, 4
418  equed = equeds( iequed )
419  IF( iequed.EQ.1 ) THEN
420  nfact = 3
421  ELSE
422  nfact = 1
423  END IF
424 *
425  DO 100 ifact = 1, nfact
426  fact = facts( ifact )
427  prefac = lsame( fact, 'F' )
428  nofact = lsame( fact, 'N' )
429  equil = lsame( fact, 'E' )
430 *
431  IF( zerot ) THEN
432  IF( prefac )
433  $ GO TO 100
434  rcondo = zero
435  rcondi = zero
436 *
437  ELSE IF( .NOT.nofact ) THEN
438 *
439 * Compute the condition number for comparison
440 * with the value returned by DGESVX (FACT =
441 * 'N' reuses the condition number from the
442 * previous iteration with FACT = 'F').
443 *
444  CALL dlacpy( 'Full', kl+ku+1, n, asav, lda,
445  $ afb( kl+1 ), ldafb )
446  IF( equil .OR. iequed.GT.1 ) THEN
447 *
448 * Compute row and column scale factors to
449 * equilibrate the matrix A.
450 *
451  CALL dgbequ( n, n, kl, ku, afb( kl+1 ),
452  $ ldafb, s, s( n+1 ), rowcnd,
453  $ colcnd, amax, info )
454  IF( info.EQ.0 .AND. n.GT.0 ) THEN
455  IF( lsame( equed, 'R' ) ) THEN
456  rowcnd = zero
457  colcnd = one
458  ELSE IF( lsame( equed, 'C' ) ) THEN
459  rowcnd = one
460  colcnd = zero
461  ELSE IF( lsame( equed, 'B' ) ) THEN
462  rowcnd = zero
463  colcnd = zero
464  END IF
465 *
466 * Equilibrate the matrix.
467 *
468  CALL dlaqgb( n, n, kl, ku, afb( kl+1 ),
469  $ ldafb, s, s( n+1 ),
470  $ rowcnd, colcnd, amax,
471  $ equed )
472  END IF
473  END IF
474 *
475 * Save the condition number of the
476 * non-equilibrated system for use in DGET04.
477 *
478  IF( equil ) THEN
479  roldo = rcondo
480  roldi = rcondi
481  END IF
482 *
483 * Compute the 1-norm and infinity-norm of A.
484 *
485  anormo = dlangb( '1', n, kl, ku, afb( kl+1 ),
486  $ ldafb, rwork )
487  anormi = dlangb( 'I', n, kl, ku, afb( kl+1 ),
488  $ ldafb, rwork )
489 *
490 * Factor the matrix A.
491 *
492  CALL dgbtrf( n, n, kl, ku, afb, ldafb, iwork,
493  $ info )
494 *
495 * Form the inverse of A.
496 *
497  CALL dlaset( 'Full', n, n, zero, one, work,
498  $ ldb )
499  srnamt = 'DGBTRS'
500  CALL dgbtrs( 'No transpose', n, kl, ku, n,
501  $ afb, ldafb, iwork, work, ldb,
502  $ info )
503 *
504 * Compute the 1-norm condition number of A.
505 *
506  ainvnm = dlange( '1', n, n, work, ldb,
507  $ rwork )
508  IF( anormo.LE.zero .OR. ainvnm.LE.zero ) THEN
509  rcondo = one
510  ELSE
511  rcondo = ( one / anormo ) / ainvnm
512  END IF
513 *
514 * Compute the infinity-norm condition number
515 * of A.
516 *
517  ainvnm = dlange( 'I', n, n, work, ldb,
518  $ rwork )
519  IF( anormi.LE.zero .OR. ainvnm.LE.zero ) THEN
520  rcondi = one
521  ELSE
522  rcondi = ( one / anormi ) / ainvnm
523  END IF
524  END IF
525 *
526  DO 90 itran = 1, ntran
527 *
528 * Do for each value of TRANS.
529 *
530  trans = transs( itran )
531  IF( itran.EQ.1 ) THEN
532  rcondc = rcondo
533  ELSE
534  rcondc = rcondi
535  END IF
536 *
537 * Restore the matrix A.
538 *
539  CALL dlacpy( 'Full', kl+ku+1, n, asav, lda,
540  $ a, lda )
541 *
542 * Form an exact solution and set the right hand
543 * side.
544 *
545  srnamt = 'DLARHS'
546  CALL dlarhs( path, xtype, 'Full', trans, n,
547  $ n, kl, ku, nrhs, a, lda, xact,
548  $ ldb, b, ldb, iseed, info )
549  xtype = 'C'
550  CALL dlacpy( 'Full', n, nrhs, b, ldb, bsav,
551  $ ldb )
552 *
553  IF( nofact .AND. itran.EQ.1 ) THEN
554 *
555 * --- Test DGBSV ---
556 *
557 * Compute the LU factorization of the matrix
558 * and solve the system.
559 *
560  CALL dlacpy( 'Full', kl+ku+1, n, a, lda,
561  $ afb( kl+1 ), ldafb )
562  CALL dlacpy( 'Full', n, nrhs, b, ldb, x,
563  $ ldb )
564 *
565  srnamt = 'DGBSV '
566  CALL dgbsv( n, kl, ku, nrhs, afb, ldafb,
567  $ iwork, x, ldb, info )
568 *
569 * Check error code from DGBSV .
570 *
571  IF( info.NE.izero )
572  $ CALL alaerh( path, 'DGBSV ', info,
573  $ izero, ' ', n, n, kl, ku,
574  $ nrhs, imat, nfail, nerrs,
575  $ nout )
576 *
577 * Reconstruct matrix from factors and
578 * compute residual.
579 *
580  CALL dgbt01( n, n, kl, ku, a, lda, afb,
581  $ ldafb, iwork, work,
582  $ result( 1 ) )
583  nt = 1
584  IF( izero.EQ.0 ) THEN
585 *
586 * Compute residual of the computed
587 * solution.
588 *
589  CALL dlacpy( 'Full', n, nrhs, b, ldb,
590  $ work, ldb )
591  CALL dgbt02( 'No transpose', n, n, kl,
592  $ ku, nrhs, a, lda, x, ldb,
593  $ work, ldb, rwork,
594  $ result( 2 ) )
595 *
596 * Check solution from generated exact
597 * solution.
598 *
599  CALL dget04( n, nrhs, x, ldb, xact,
600  $ ldb, rcondc, result( 3 ) )
601  nt = 3
602  END IF
603 *
604 * Print information about the tests that did
605 * not pass the threshold.
606 *
607  DO 50 k = 1, nt
608  IF( result( k ).GE.thresh ) THEN
609  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
610  $ CALL aladhd( nout, path )
611  WRITE( nout, fmt = 9997 )'DGBSV ',
612  $ n, kl, ku, imat, k, result( k )
613  nfail = nfail + 1
614  END IF
615  50 CONTINUE
616  nrun = nrun + nt
617  END IF
618 *
619 * --- Test DGBSVX ---
620 *
621  IF( .NOT.prefac )
622  $ CALL dlaset( 'Full', 2*kl+ku+1, n, zero,
623  $ zero, afb, ldafb )
624  CALL dlaset( 'Full', n, nrhs, zero, zero, x,
625  $ ldb )
626  IF( iequed.GT.1 .AND. n.GT.0 ) THEN
627 *
628 * Equilibrate the matrix if FACT = 'F' and
629 * EQUED = 'R', 'C', or 'B'.
630 *
631  CALL dlaqgb( n, n, kl, ku, a, lda, s,
632  $ s( n+1 ), rowcnd, colcnd,
633  $ amax, equed )
634  END IF
635 *
636 * Solve the system and compute the condition
637 * number and error bounds using DGBSVX.
638 *
639  srnamt = 'DGBSVX'
640  CALL dgbsvx( fact, trans, n, kl, ku, nrhs, a,
641  $ lda, afb, ldafb, iwork, equed,
642  $ s, s( n+1 ), b, ldb, x, ldb,
643  $ rcond, rwork, rwork( nrhs+1 ),
644  $ work, iwork( n+1 ), info )
645 *
646 * Check the error code from DGBSVX.
647 *
648  IF( info.NE.izero )
649  $ CALL alaerh( path, 'DGBSVX', info, izero,
650  $ fact // trans, n, n, kl, ku,
651  $ nrhs, imat, nfail, nerrs,
652  $ nout )
653 *
654 * Compare WORK(1) from DGBSVX with the computed
655 * reciprocal pivot growth factor RPVGRW
656 *
657  IF( info.NE.0 ) THEN
658  anrmpv = zero
659  DO 70 j = 1, info
660  DO 60 i = max( ku+2-j, 1 ),
661  $ min( n+ku+1-j, kl+ku+1 )
662  anrmpv = max( anrmpv,
663  $ abs( a( i+( j-1 )*lda ) ) )
664  60 CONTINUE
665  70 CONTINUE
666  rpvgrw = dlantb( 'M', 'U', 'N', info,
667  $ min( info-1, kl+ku ),
668  $ afb( max( 1, kl+ku+2-info ) ),
669  $ ldafb, work )
670  IF( rpvgrw.EQ.zero ) THEN
671  rpvgrw = one
672  ELSE
673  rpvgrw = anrmpv / rpvgrw
674  END IF
675  ELSE
676  rpvgrw = dlantb( 'M', 'U', 'N', n, kl+ku,
677  $ afb, ldafb, work )
678  IF( rpvgrw.EQ.zero ) THEN
679  rpvgrw = one
680  ELSE
681  rpvgrw = dlangb( 'M', n, kl, ku, a,
682  $ lda, work ) / rpvgrw
683  END IF
684  END IF
685  result( 7 ) = abs( rpvgrw-work( 1 ) ) /
686  $ max( work( 1 ), rpvgrw ) /
687  $ dlamch( 'E' )
688 *
689  IF( .NOT.prefac ) THEN
690 *
691 * Reconstruct matrix from factors and
692 * compute residual.
693 *
694  CALL dgbt01( n, n, kl, ku, a, lda, afb,
695  $ ldafb, iwork, work,
696  $ result( 1 ) )
697  k1 = 1
698  ELSE
699  k1 = 2
700  END IF
701 *
702  IF( info.EQ.0 ) THEN
703  trfcon = .false.
704 *
705 * Compute residual of the computed solution.
706 *
707  CALL dlacpy( 'Full', n, nrhs, bsav, ldb,
708  $ work, ldb )
709  CALL dgbt02( trans, n, n, kl, ku, nrhs,
710  $ asav, lda, x, ldb, work, ldb,
711  $ rwork( 2*nrhs+1 ),
712  $ result( 2 ) )
713 *
714 * Check solution from generated exact
715 * solution.
716 *
717  IF( nofact .OR. ( prefac .AND.
718  $ lsame( equed, 'N' ) ) ) THEN
719  CALL dget04( n, nrhs, x, ldb, xact,
720  $ ldb, rcondc, result( 3 ) )
721  ELSE
722  IF( itran.EQ.1 ) THEN
723  roldc = roldo
724  ELSE
725  roldc = roldi
726  END IF
727  CALL dget04( n, nrhs, x, ldb, xact,
728  $ ldb, roldc, result( 3 ) )
729  END IF
730 *
731 * Check the error bounds from iterative
732 * refinement.
733 *
734  CALL dgbt05( trans, n, kl, ku, nrhs, asav,
735  $ lda, b, ldb, x, ldb, xact,
736  $ ldb, rwork, rwork( nrhs+1 ),
737  $ result( 4 ) )
738  ELSE
739  trfcon = .true.
740  END IF
741 *
742 * Compare RCOND from DGBSVX with the computed
743 * value in RCONDC.
744 *
745  result( 6 ) = dget06( rcond, rcondc )
746 *
747 * Print information about the tests that did
748 * not pass the threshold.
749 *
750  IF( .NOT.trfcon ) THEN
751  DO 80 k = k1, ntests
752  IF( result( k ).GE.thresh ) THEN
753  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
754  $ CALL aladhd( nout, path )
755  IF( prefac ) THEN
756  WRITE( nout, fmt = 9995 )
757  $ 'DGBSVX', fact, trans, n, kl,
758  $ ku, equed, imat, k,
759  $ result( k )
760  ELSE
761  WRITE( nout, fmt = 9996 )
762  $ 'DGBSVX', fact, trans, n, kl,
763  $ ku, imat, k, result( k )
764  END IF
765  nfail = nfail + 1
766  END IF
767  80 CONTINUE
768  nrun = nrun + 7 - k1
769  ELSE
770  IF( result( 1 ).GE.thresh .AND. .NOT.
771  $ prefac ) THEN
772  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
773  $ CALL aladhd( nout, path )
774  IF( prefac ) THEN
775  WRITE( nout, fmt = 9995 )'DGBSVX',
776  $ fact, trans, n, kl, ku, equed,
777  $ imat, 1, result( 1 )
778  ELSE
779  WRITE( nout, fmt = 9996 )'DGBSVX',
780  $ fact, trans, n, kl, ku, imat, 1,
781  $ result( 1 )
782  END IF
783  nfail = nfail + 1
784  nrun = nrun + 1
785  END IF
786  IF( result( 6 ).GE.thresh ) THEN
787  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
788  $ CALL aladhd( nout, path )
789  IF( prefac ) THEN
790  WRITE( nout, fmt = 9995 )'DGBSVX',
791  $ fact, trans, n, kl, ku, equed,
792  $ imat, 6, result( 6 )
793  ELSE
794  WRITE( nout, fmt = 9996 )'DGBSVX',
795  $ fact, trans, n, kl, ku, imat, 6,
796  $ result( 6 )
797  END IF
798  nfail = nfail + 1
799  nrun = nrun + 1
800  END IF
801  IF( result( 7 ).GE.thresh ) THEN
802  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
803  $ CALL aladhd( nout, path )
804  IF( prefac ) THEN
805  WRITE( nout, fmt = 9995 )'DGBSVX',
806  $ fact, trans, n, kl, ku, equed,
807  $ imat, 7, result( 7 )
808  ELSE
809  WRITE( nout, fmt = 9996 )'DGBSVX',
810  $ fact, trans, n, kl, ku, imat, 7,
811  $ result( 7 )
812  END IF
813  nfail = nfail + 1
814  nrun = nrun + 1
815  END IF
816 *
817  END IF
818 *
819 * --- Test DGBSVXX ---
820 *
821 * Restore the matrices A and B.
822 *
823  CALL dlacpy( 'Full', kl+ku+1, n, asav, lda, a,
824  $ lda )
825  CALL dlacpy( 'Full', n, nrhs, bsav, ldb, b, ldb )
826 
827  IF( .NOT.prefac )
828  $ CALL dlaset( 'Full', 2*kl+ku+1, n, zero, zero,
829  $ afb, ldafb )
830  CALL dlaset( 'Full', n, nrhs, zero, zero, x, ldb )
831  IF( iequed.GT.1 .AND. n.GT.0 ) THEN
832 *
833 * Equilibrate the matrix if FACT = 'F' and
834 * EQUED = 'R', 'C', or 'B'.
835 *
836  CALL dlaqgb( n, n, kl, ku, a, lda, s, s( n+1 ),
837  $ rowcnd, colcnd, amax, equed )
838  END IF
839 *
840 * Solve the system and compute the condition number
841 * and error bounds using DGBSVXX.
842 *
843  srnamt = 'DGBSVXX'
844  n_err_bnds = 3
845  CALL dgbsvxx( fact, trans, n, kl, ku, nrhs, a, lda,
846  $ afb, ldafb, iwork, equed, s, s( n+1 ), b, ldb,
847  $ x, ldb, rcond, rpvgrw_svxx, berr, n_err_bnds,
848  $ errbnds_n, errbnds_c, 0, zero, work,
849  $ iwork( n+1 ), info )
850 *
851 * Check the error code from DGBSVXX.
852 *
853  IF( info.EQ.n+1 ) GOTO 90
854  IF( info.NE.izero ) THEN
855  CALL alaerh( path, 'DGBSVXX', info, izero,
856  $ fact // trans, n, n, -1, -1, nrhs,
857  $ imat, nfail, nerrs, nout )
858  GOTO 90
859  END IF
860 *
861 * Compare rpvgrw_svxx from DGBSVXX with the computed
862 * reciprocal pivot growth factor RPVGRW
863 *
864 
865  IF ( info .GT. 0 .AND. info .LT. n+1 ) THEN
866  rpvgrw = dla_gbrpvgrw(n, kl, ku, info, a, lda,
867  $ afb, ldafb)
868  ELSE
869  rpvgrw = dla_gbrpvgrw(n, kl, ku, n, a, lda,
870  $ afb, ldafb)
871  ENDIF
872 
873  result( 7 ) = abs( rpvgrw-rpvgrw_svxx ) /
874  $ max( rpvgrw_svxx, rpvgrw ) /
875  $ dlamch( 'E' )
876 *
877  IF( .NOT.prefac ) THEN
878 *
879 * Reconstruct matrix from factors and compute
880 * residual.
881 *
882  CALL dgbt01( n, n, kl, ku, a, lda, afb, ldafb,
883  $ iwork, work, result( 1 ) )
884  k1 = 1
885  ELSE
886  k1 = 2
887  END IF
888 *
889  IF( info.EQ.0 ) THEN
890  trfcon = .false.
891 *
892 * Compute residual of the computed solution.
893 *
894  CALL dlacpy( 'Full', n, nrhs, bsav, ldb, work,
895  $ ldb )
896  CALL dgbt02( trans, n, n, kl, ku, nrhs, asav,
897  $ lda, x, ldb, work, ldb, rwork,
898  $ result( 2 ) )
899 *
900 * Check solution from generated exact solution.
901 *
902  IF( nofact .OR. ( prefac .AND. lsame( equed,
903  $ 'N' ) ) ) THEN
904  CALL dget04( n, nrhs, x, ldb, xact, ldb,
905  $ rcondc, result( 3 ) )
906  ELSE
907  IF( itran.EQ.1 ) THEN
908  roldc = roldo
909  ELSE
910  roldc = roldi
911  END IF
912  CALL dget04( n, nrhs, x, ldb, xact, ldb,
913  $ roldc, result( 3 ) )
914  END IF
915  ELSE
916  trfcon = .true.
917  END IF
918 *
919 * Compare RCOND from DGBSVXX with the computed value
920 * in RCONDC.
921 *
922  result( 6 ) = dget06( rcond, rcondc )
923 *
924 * Print information about the tests that did not pass
925 * the threshold.
926 *
927  IF( .NOT.trfcon ) THEN
928  DO 45 k = k1, ntests
929  IF( result( k ).GE.thresh ) THEN
930  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
931  $ CALL aladhd( nout, path )
932  IF( prefac ) THEN
933  WRITE( nout, fmt = 9995 )'DGBSVXX',
934  $ fact, trans, n, kl, ku, equed,
935  $ imat, k, result( k )
936  ELSE
937  WRITE( nout, fmt = 9996 )'DGBSVXX',
938  $ fact, trans, n, kl, ku, imat, k,
939  $ result( k )
940  END IF
941  nfail = nfail + 1
942  END IF
943  45 CONTINUE
944  nrun = nrun + 7 - k1
945  ELSE
946  IF( result( 1 ).GE.thresh .AND. .NOT.prefac )
947  $ THEN
948  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
949  $ CALL aladhd( nout, path )
950  IF( prefac ) THEN
951  WRITE( nout, fmt = 9995 )'DGBSVXX', fact,
952  $ trans, n, kl, ku, equed, imat, 1,
953  $ result( 1 )
954  ELSE
955  WRITE( nout, fmt = 9996 )'DGBSVXX', fact,
956  $ trans, n, kl, ku, imat, 1,
957  $ result( 1 )
958  END IF
959  nfail = nfail + 1
960  nrun = nrun + 1
961  END IF
962  IF( result( 6 ).GE.thresh ) THEN
963  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
964  $ CALL aladhd( nout, path )
965  IF( prefac ) THEN
966  WRITE( nout, fmt = 9995 )'DGBSVXX', fact,
967  $ trans, n, kl, ku, equed, imat, 6,
968  $ result( 6 )
969  ELSE
970  WRITE( nout, fmt = 9996 )'DGBSVXX', fact,
971  $ trans, n, kl, ku, imat, 6,
972  $ result( 6 )
973  END IF
974  nfail = nfail + 1
975  nrun = nrun + 1
976  END IF
977  IF( result( 7 ).GE.thresh ) THEN
978  IF( nfail.EQ.0 .AND. nerrs.EQ.0 )
979  $ CALL aladhd( nout, path )
980  IF( prefac ) THEN
981  WRITE( nout, fmt = 9995 )'DGBSVXX', fact,
982  $ trans, n, kl, ku, equed, imat, 7,
983  $ result( 7 )
984  ELSE
985  WRITE( nout, fmt = 9996 )'DGBSVXX', fact,
986  $ trans, n, kl, ku, imat, 7,
987  $ result( 7 )
988  END IF
989  nfail = nfail + 1
990  nrun = nrun + 1
991  END IF
992 *
993  END IF
994  90 CONTINUE
995  100 CONTINUE
996  110 CONTINUE
997  120 CONTINUE
998  130 CONTINUE
999  140 CONTINUE
1000  150 CONTINUE
1001 *
1002 * Print a summary of the results.
1003 *
1004  CALL alasvm( path, nout, nfail, nrun, nerrs )
1005 
1006 * Test Error Bounds from DGBSVXX
1007 
1008  CALL debchvxx(thresh, path)
1009 
1010  9999 FORMAT( ' *** In DDRVGB, LA=', i5, ' is too small for N=', i5,
1011  $ ', KU=', i5, ', KL=', i5, / ' ==> Increase LA to at least ',
1012  $ i5 )
1013  9998 FORMAT( ' *** In DDRVGB, LAFB=', i5, ' is too small for N=', i5,
1014  $ ', KU=', i5, ', KL=', i5, /
1015  $ ' ==> Increase LAFB to at least ', i5 )
1016  9997 FORMAT( 1x, a, ', N=', i5, ', KL=', i5, ', KU=', i5, ', type ',
1017  $ i1, ', test(', i1, ')=', g12.5 )
1018  9996 FORMAT( 1x, a, '( ''', a1, ''',''', a1, ''',', i5, ',', i5, ',',
1019  $ i5, ',...), type ', i1, ', test(', i1, ')=', g12.5 )
1020  9995 FORMAT( 1x, a, '( ''', a1, ''',''', a1, ''',', i5, ',', i5, ',',
1021  $ i5, ',...), EQUED=''', a1, ''', type ', i1, ', test(', i1,
1022  $ ')=', g12.5 )
1023 *
1024  RETURN
1025 *
1026 * End of DDRVGBX
1027 *
1028  END
dlacpy
subroutine dlacpy(UPLO, M, N, A, LDA, B, LDB)
DLACPY copies all or part of one two-dimensional array to another.
Definition: dlacpy.f:103
dlaset
subroutine dlaset(UPLO, M, N, ALPHA, BETA, A, LDA)
DLASET initializes the off-diagonal elements and the diagonal elements of a matrix to given values.
Definition: dlaset.f:110
alasvm
subroutine alasvm(TYPE, NOUT, NFAIL, NRUN, NERRS)
ALASVM
Definition: alasvm.f:73
xlaenv
subroutine xlaenv(ISPEC, NVALUE)
XLAENV
Definition: xlaenv.f:81
aladhd
subroutine aladhd(IOUNIT, PATH)
ALADHD
Definition: aladhd.f:90
alaerh
subroutine alaerh(PATH, SUBNAM, INFO, INFOE, OPTS, M, N, KL, KU, N5, IMAT, NFAIL, NERRS, NOUT)
ALAERH
Definition: alaerh.f:147
dlarhs
subroutine dlarhs(PATH, XTYPE, UPLO, TRANS, M, N, KL, KU, NRHS, A, LDA, X, LDX, B, LDB, ISEED, INFO)
DLARHS
Definition: dlarhs.f:205
dget04
subroutine dget04(N, NRHS, X, LDX, XACT, LDXACT, RCOND, RESID)
DGET04
Definition: dget04.f:102
dgbt01
subroutine dgbt01(M, N, KL, KU, A, LDA, AFAC, LDAFAC, IPIV, WORK, RESID)
DGBT01
Definition: dgbt01.f:126
dgbt05
subroutine dgbt05(TRANS, N, KL, KU, NRHS, AB, LDAB, B, LDB, X, LDX, XACT, LDXACT, FERR, BERR, RESLTS)
DGBT05
Definition: dgbt05.f:176
ddrvgb
subroutine ddrvgb(DOTYPE, NN, NVAL, NRHS, THRESH, TSTERR, A, LA, AFB, LAFB, ASAV, B, BSAV, X, XACT, S, WORK, RWORK, IWORK, NOUT)
DDRVGB
Definition: ddrvgb.f:172
dgbt02
subroutine dgbt02(TRANS, M, N, KL, KU, NRHS, A, LDA, X, LDX, B, LDB, RWORK, RESID)
DGBT02
Definition: dgbt02.f:149
dlatb4
subroutine dlatb4(PATH, IMAT, M, N, TYPE, KL, KU, ANORM, MODE, CNDNUM, DIST)
DLATB4
Definition: dlatb4.f:120
derrvx
subroutine derrvx(PATH, NUNIT)
DERRVX
Definition: derrvx.f:55
debchvxx
subroutine debchvxx(THRESH, PATH)
DEBCHVXX
Definition: debchvxx.f:96
dlatms
subroutine dlatms(M, N, DIST, ISEED, SYM, D, MODE, COND, DMAX, KL, KU, PACK, A, LDA, WORK, INFO)
DLATMS
Definition: dlatms.f:321
dlaqgb
subroutine dlaqgb(M, N, KL, KU, AB, LDAB, R, C, ROWCND, COLCND, AMAX, EQUED)
DLAQGB scales a general band matrix, using row and column scaling factors computed by sgbequ.
Definition: dlaqgb.f:159
dla_gbrpvgrw
double precision function dla_gbrpvgrw(N, KL, KU, NCOLS, AB, LDAB, AFB, LDAFB)
DLA_GBRPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a general banded matrix.
Definition: dla_gbrpvgrw.f:117
dgbtrs
subroutine dgbtrs(TRANS, N, KL, KU, NRHS, AB, LDAB, IPIV, B, LDB, INFO)
DGBTRS
Definition: dgbtrs.f:138
dgbequb
subroutine dgbequb(M, N, KL, KU, AB, LDAB, R, C, ROWCND, COLCND, AMAX, INFO)
DGBEQUB
Definition: dgbequb.f:160
dgbtrf
subroutine dgbtrf(M, N, KL, KU, AB, LDAB, IPIV, INFO)
DGBTRF
Definition: dgbtrf.f:144
dgbequ
subroutine dgbequ(M, N, KL, KU, AB, LDAB, R, C, ROWCND, COLCND, AMAX, INFO)
DGBEQU
Definition: dgbequ.f:153
dgbsvx
subroutine dgbsvx(FACT, TRANS, N, KL, KU, NRHS, AB, LDAB, AFB, LDAFB, IPIV, EQUED, R, C, B, LDB, X, LDX, RCOND, FERR, BERR, WORK, IWORK, INFO)
DGBSVX computes the solution to system of linear equations A * X = B for GB matrices
Definition: dgbsvx.f:369
dgbsvxx
subroutine dgbsvxx(FACT, TRANS, N, KL, KU, NRHS, AB, LDAB, AFB, LDAFB, IPIV, EQUED, R, C, B, LDB, X, LDX, RCOND, RPVGRW, BERR, N_ERR_BNDS, ERR_BNDS_NORM, ERR_BNDS_COMP, NPARAMS, PARAMS, WORK, IWORK, INFO)
DGBSVXX computes the solution to system of linear equations A * X = B for GB matrices
Definition: dgbsvxx.f:560
dgbsv
subroutine dgbsv(N, KL, KU, NRHS, AB, LDAB, IPIV, B, LDB, INFO)
DGBSV computes the solution to system of linear equations A * X = B for GB matrices (simple driver)
Definition: dgbsv.f:162