LAPACK  3.10.1
LAPACK: Linear Algebra PACKage
dchkbb.f
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1 *> \brief \b DCHKBB
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 DCHKBB( NSIZES, MVAL, NVAL, NWDTHS, KK, NTYPES, DOTYPE,
12 * NRHS, ISEED, THRESH, NOUNIT, A, LDA, AB, LDAB,
13 * BD, BE, Q, LDQ, P, LDP, C, LDC, CC, WORK,
14 * LWORK, RESULT, INFO )
15 *
16 * .. Scalar Arguments ..
17 * INTEGER INFO, LDA, LDAB, LDC, LDP, LDQ, LWORK, NOUNIT,
18 * $ NRHS, NSIZES, NTYPES, NWDTHS
19 * DOUBLE PRECISION THRESH
20 * ..
21 * .. Array Arguments ..
22 * LOGICAL DOTYPE( * )
23 * INTEGER ISEED( 4 ), KK( * ), MVAL( * ), NVAL( * )
24 * DOUBLE PRECISION A( LDA, * ), AB( LDAB, * ), BD( * ), BE( * ),
25 * $ C( LDC, * ), CC( LDC, * ), P( LDP, * ),
26 * $ Q( LDQ, * ), RESULT( * ), WORK( * )
27 * ..
28 *
29 *
30 *> \par Purpose:
31 * =============
32 *>
33 *> \verbatim
34 *>
35 *> DCHKBB tests the reduction of a general real rectangular band
36 *> matrix to bidiagonal form.
37 *>
38 *> DGBBRD factors a general band matrix A as Q B P* , where * means
39 *> transpose, B is upper bidiagonal, and Q and P are orthogonal;
40 *> DGBBRD can also overwrite a given matrix C with Q* C .
41 *>
42 *> For each pair of matrix dimensions (M,N) and each selected matrix
43 *> type, an M by N matrix A and an M by NRHS matrix C are generated.
44 *> The problem dimensions are as follows
45 *> A: M x N
46 *> Q: M x M
47 *> P: N x N
48 *> B: min(M,N) x min(M,N)
49 *> C: M x NRHS
50 *>
51 *> For each generated matrix, 4 tests are performed:
52 *>
53 *> (1) | A - Q B PT | / ( |A| max(M,N) ulp ), PT = P'
54 *>
55 *> (2) | I - Q' Q | / ( M ulp )
56 *>
57 *> (3) | I - PT PT' | / ( N ulp )
58 *>
59 *> (4) | Y - Q' C | / ( |Y| max(M,NRHS) ulp ), where Y = Q' C.
60 *>
61 *> The "types" are specified by a logical array DOTYPE( 1:NTYPES );
62 *> if DOTYPE(j) is .TRUE., then matrix type "j" will be generated.
63 *> Currently, the list of possible types is:
64 *>
65 *> The possible matrix types are
66 *>
67 *> (1) The zero matrix.
68 *> (2) The identity matrix.
69 *>
70 *> (3) A diagonal matrix with evenly spaced entries
71 *> 1, ..., ULP and random signs.
72 *> (ULP = (first number larger than 1) - 1 )
73 *> (4) A diagonal matrix with geometrically spaced entries
74 *> 1, ..., ULP and random signs.
75 *> (5) A diagonal matrix with "clustered" entries 1, ULP, ..., ULP
76 *> and random signs.
77 *>
78 *> (6) Same as (3), but multiplied by SQRT( overflow threshold )
79 *> (7) Same as (3), but multiplied by SQRT( underflow threshold )
80 *>
81 *> (8) A matrix of the form U D V, where U and V are orthogonal and
82 *> D has evenly spaced entries 1, ..., ULP with random signs
83 *> on the diagonal.
84 *>
85 *> (9) A matrix of the form U D V, where U and V are orthogonal and
86 *> D has geometrically spaced entries 1, ..., ULP with random
87 *> signs on the diagonal.
88 *>
89 *> (10) A matrix of the form U D V, where U and V are orthogonal and
90 *> D has "clustered" entries 1, ULP,..., ULP with random
91 *> signs on the diagonal.
92 *>
93 *> (11) Same as (8), but multiplied by SQRT( overflow threshold )
94 *> (12) Same as (8), but multiplied by SQRT( underflow threshold )
95 *>
96 *> (13) Rectangular matrix with random entries chosen from (-1,1).
97 *> (14) Same as (13), but multiplied by SQRT( overflow threshold )
98 *> (15) Same as (13), but multiplied by SQRT( underflow threshold )
99 *> \endverbatim
100 *
101 * Arguments:
102 * ==========
103 *
104 *> \param[in] NSIZES
105 *> \verbatim
106 *> NSIZES is INTEGER
107 *> The number of values of M and N contained in the vectors
108 *> MVAL and NVAL. The matrix sizes are used in pairs (M,N).
109 *> If NSIZES is zero, DCHKBB does nothing. NSIZES must be at
110 *> least zero.
111 *> \endverbatim
112 *>
113 *> \param[in] MVAL
114 *> \verbatim
115 *> MVAL is INTEGER array, dimension (NSIZES)
116 *> The values of the matrix row dimension M.
117 *> \endverbatim
118 *>
119 *> \param[in] NVAL
120 *> \verbatim
121 *> NVAL is INTEGER array, dimension (NSIZES)
122 *> The values of the matrix column dimension N.
123 *> \endverbatim
124 *>
125 *> \param[in] NWDTHS
126 *> \verbatim
127 *> NWDTHS is INTEGER
128 *> The number of bandwidths to use. If it is zero,
129 *> DCHKBB does nothing. It must be at least zero.
130 *> \endverbatim
131 *>
132 *> \param[in] KK
133 *> \verbatim
134 *> KK is INTEGER array, dimension (NWDTHS)
135 *> An array containing the bandwidths to be used for the band
136 *> matrices. The values must be at least zero.
137 *> \endverbatim
138 *>
139 *> \param[in] NTYPES
140 *> \verbatim
141 *> NTYPES is INTEGER
142 *> The number of elements in DOTYPE. If it is zero, DCHKBB
143 *> does nothing. It must be at least zero. If it is MAXTYP+1
144 *> and NSIZES is 1, then an additional type, MAXTYP+1 is
145 *> defined, which is to use whatever matrix is in A. This
146 *> is only useful if DOTYPE(1:MAXTYP) is .FALSE. and
147 *> DOTYPE(MAXTYP+1) is .TRUE. .
148 *> \endverbatim
149 *>
150 *> \param[in] DOTYPE
151 *> \verbatim
152 *> DOTYPE is LOGICAL array, dimension (NTYPES)
153 *> If DOTYPE(j) is .TRUE., then for each size in NN a
154 *> matrix of that size and of type j will be generated.
155 *> If NTYPES is smaller than the maximum number of types
156 *> defined (PARAMETER MAXTYP), then types NTYPES+1 through
157 *> MAXTYP will not be generated. If NTYPES is larger
158 *> than MAXTYP, DOTYPE(MAXTYP+1) through DOTYPE(NTYPES)
159 *> will be ignored.
160 *> \endverbatim
161 *>
162 *> \param[in] NRHS
163 *> \verbatim
164 *> NRHS is INTEGER
165 *> The number of columns in the "right-hand side" matrix C.
166 *> If NRHS = 0, then the operations on the right-hand side will
167 *> not be tested. NRHS must be at least 0.
168 *> \endverbatim
169 *>
170 *> \param[in,out] ISEED
171 *> \verbatim
172 *> ISEED is INTEGER array, dimension (4)
173 *> On entry ISEED specifies the seed of the random number
174 *> generator. The array elements should be between 0 and 4095;
175 *> if not they will be reduced mod 4096. Also, ISEED(4) must
176 *> be odd. The random number generator uses a linear
177 *> congruential sequence limited to small integers, and so
178 *> should produce machine independent random numbers. The
179 *> values of ISEED are changed on exit, and can be used in the
180 *> next call to DCHKBB to continue the same random number
181 *> sequence.
182 *> \endverbatim
183 *>
184 *> \param[in] THRESH
185 *> \verbatim
186 *> THRESH is DOUBLE PRECISION
187 *> A test will count as "failed" if the "error", computed as
188 *> described above, exceeds THRESH. Note that the error
189 *> is scaled to be O(1), so THRESH should be a reasonably
190 *> small multiple of 1, e.g., 10 or 100. In particular,
191 *> it should not depend on the precision (single vs. double)
192 *> or the size of the matrix. It must be at least zero.
193 *> \endverbatim
194 *>
195 *> \param[in] NOUNIT
196 *> \verbatim
197 *> NOUNIT is INTEGER
198 *> The FORTRAN unit number for printing out error messages
199 *> (e.g., if a routine returns IINFO not equal to 0.)
200 *> \endverbatim
201 *>
202 *> \param[in,out] A
203 *> \verbatim
204 *> A is DOUBLE PRECISION array, dimension
205 *> (LDA, max(NN))
206 *> Used to hold the matrix A.
207 *> \endverbatim
208 *>
209 *> \param[in] LDA
210 *> \verbatim
211 *> LDA is INTEGER
212 *> The leading dimension of A. It must be at least 1
213 *> and at least max( NN ).
214 *> \endverbatim
215 *>
216 *> \param[out] AB
217 *> \verbatim
218 *> AB is DOUBLE PRECISION array, dimension (LDAB, max(NN))
219 *> Used to hold A in band storage format.
220 *> \endverbatim
221 *>
222 *> \param[in] LDAB
223 *> \verbatim
224 *> LDAB is INTEGER
225 *> The leading dimension of AB. It must be at least 2 (not 1!)
226 *> and at least max( KK )+1.
227 *> \endverbatim
228 *>
229 *> \param[out] BD
230 *> \verbatim
231 *> BD is DOUBLE PRECISION array, dimension (max(NN))
232 *> Used to hold the diagonal of the bidiagonal matrix computed
233 *> by DGBBRD.
234 *> \endverbatim
235 *>
236 *> \param[out] BE
237 *> \verbatim
238 *> BE is DOUBLE PRECISION array, dimension (max(NN))
239 *> Used to hold the off-diagonal of the bidiagonal matrix
240 *> computed by DGBBRD.
241 *> \endverbatim
242 *>
243 *> \param[out] Q
244 *> \verbatim
245 *> Q is DOUBLE PRECISION array, dimension (LDQ, max(NN))
246 *> Used to hold the orthogonal matrix Q computed by DGBBRD.
247 *> \endverbatim
248 *>
249 *> \param[in] LDQ
250 *> \verbatim
251 *> LDQ is INTEGER
252 *> The leading dimension of Q. It must be at least 1
253 *> and at least max( NN ).
254 *> \endverbatim
255 *>
256 *> \param[out] P
257 *> \verbatim
258 *> P is DOUBLE PRECISION array, dimension (LDP, max(NN))
259 *> Used to hold the orthogonal matrix P computed by DGBBRD.
260 *> \endverbatim
261 *>
262 *> \param[in] LDP
263 *> \verbatim
264 *> LDP is INTEGER
265 *> The leading dimension of P. It must be at least 1
266 *> and at least max( NN ).
267 *> \endverbatim
268 *>
269 *> \param[out] C
270 *> \verbatim
271 *> C is DOUBLE PRECISION array, dimension (LDC, max(NN))
272 *> Used to hold the matrix C updated by DGBBRD.
273 *> \endverbatim
274 *>
275 *> \param[in] LDC
276 *> \verbatim
277 *> LDC is INTEGER
278 *> The leading dimension of U. It must be at least 1
279 *> and at least max( NN ).
280 *> \endverbatim
281 *>
282 *> \param[out] CC
283 *> \verbatim
284 *> CC is DOUBLE PRECISION array, dimension (LDC, max(NN))
285 *> Used to hold a copy of the matrix C.
286 *> \endverbatim
287 *>
288 *> \param[out] WORK
289 *> \verbatim
290 *> WORK is DOUBLE PRECISION array, dimension (LWORK)
291 *> \endverbatim
292 *>
293 *> \param[in] LWORK
294 *> \verbatim
295 *> LWORK is INTEGER
296 *> The number of entries in WORK. This must be at least
297 *> max( LDA+1, max(NN)+1 )*max(NN).
298 *> \endverbatim
299 *>
300 *> \param[out] RESULT
301 *> \verbatim
302 *> RESULT is DOUBLE PRECISION array, dimension (4)
303 *> The values computed by the tests described above.
304 *> The values are currently limited to 1/ulp, to avoid
305 *> overflow.
306 *> \endverbatim
307 *>
308 *> \param[out] INFO
309 *> \verbatim
310 *> INFO is INTEGER
311 *> If 0, then everything ran OK.
312 *>
313 *>-----------------------------------------------------------------------
314 *>
315 *> Some Local Variables and Parameters:
316 *> ---- ----- --------- --- ----------
317 *> ZERO, ONE Real 0 and 1.
318 *> MAXTYP The number of types defined.
319 *> NTEST The number of tests performed, or which can
320 *> be performed so far, for the current matrix.
321 *> NTESTT The total number of tests performed so far.
322 *> NMAX Largest value in NN.
323 *> NMATS The number of matrices generated so far.
324 *> NERRS The number of tests which have exceeded THRESH
325 *> so far.
326 *> COND, IMODE Values to be passed to the matrix generators.
327 *> ANORM Norm of A; passed to matrix generators.
328 *>
329 *> OVFL, UNFL Overflow and underflow thresholds.
330 *> ULP, ULPINV Finest relative precision and its inverse.
331 *> RTOVFL, RTUNFL Square roots of the previous 2 values.
332 *> The following four arrays decode JTYPE:
333 *> KTYPE(j) The general type (1-10) for type "j".
334 *> KMODE(j) The MODE value to be passed to the matrix
335 *> generator for type "j".
336 *> KMAGN(j) The order of magnitude ( O(1),
337 *> O(overflow^(1/2) ), O(underflow^(1/2) )
338 *> \endverbatim
339 *
340 * Authors:
341 * ========
342 *
343 *> \author Univ. of Tennessee
344 *> \author Univ. of California Berkeley
345 *> \author Univ. of Colorado Denver
346 *> \author NAG Ltd.
347 *
348 *> \ingroup double_eig
349 *
350 * =====================================================================
351  SUBROUTINE dchkbb( NSIZES, MVAL, NVAL, NWDTHS, KK, NTYPES, DOTYPE,
352  $ NRHS, ISEED, THRESH, NOUNIT, A, LDA, AB, LDAB,
353  $ BD, BE, Q, LDQ, P, LDP, C, LDC, CC, WORK,
354  $ LWORK, RESULT, INFO )
355 *
356 * -- LAPACK test routine (input) --
357 * -- LAPACK is a software package provided by Univ. of Tennessee, --
358 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
359 *
360 * .. Scalar Arguments ..
361  INTEGER INFO, LDA, LDAB, LDC, LDP, LDQ, LWORK, NOUNIT,
362  $ NRHS, NSIZES, NTYPES, NWDTHS
363  DOUBLE PRECISION THRESH
364 * ..
365 * .. Array Arguments ..
366  LOGICAL DOTYPE( * )
367  INTEGER ISEED( 4 ), KK( * ), MVAL( * ), NVAL( * )
368  DOUBLE PRECISION A( LDA, * ), AB( LDAB, * ), BD( * ), BE( * ),
369  $ c( ldc, * ), cc( ldc, * ), p( ldp, * ),
370  $ q( ldq, * ), result( * ), work( * )
371 * ..
372 *
373 * =====================================================================
374 *
375 * .. Parameters ..
376  DOUBLE PRECISION ZERO, ONE
377  PARAMETER ( ZERO = 0.0d0, one = 1.0d0 )
378  INTEGER MAXTYP
379  parameter( maxtyp = 15 )
380 * ..
381 * .. Local Scalars ..
382  LOGICAL BADMM, BADNN, BADNNB
383  INTEGER I, IINFO, IMODE, ITYPE, J, JCOL, JR, JSIZE,
384  $ JTYPE, JWIDTH, K, KL, KMAX, KU, M, MMAX, MNMAX,
385  $ mnmin, mtypes, n, nerrs, nmats, nmax, ntest,
386  $ ntestt
387  DOUBLE PRECISION AMNINV, ANORM, COND, OVFL, RTOVFL, RTUNFL, ULP,
388  $ ULPINV, UNFL
389 * ..
390 * .. Local Arrays ..
391  INTEGER IDUMMA( 1 ), IOLDSD( 4 ), KMAGN( MAXTYP ),
392  $ KMODE( MAXTYP ), KTYPE( MAXTYP )
393 * ..
394 * .. External Functions ..
395  DOUBLE PRECISION DLAMCH
396  EXTERNAL DLAMCH
397 * ..
398 * .. External Subroutines ..
399  EXTERNAL dbdt01, dbdt02, dgbbrd, dlacpy, dlahd2, dlaset,
401 * ..
402 * .. Intrinsic Functions ..
403  INTRINSIC abs, dble, max, min, sqrt
404 * ..
405 * .. Data statements ..
406  DATA ktype / 1, 2, 5*4, 5*6, 3*9 /
407  DATA kmagn / 2*1, 3*1, 2, 3, 3*1, 2, 3, 1, 2, 3 /
408  DATA kmode / 2*0, 4, 3, 1, 4, 4, 4, 3, 1, 4, 4, 0,
409  $ 0, 0 /
410 * ..
411 * .. Executable Statements ..
412 *
413 * Check for errors
414 *
415  ntestt = 0
416  info = 0
417 *
418 * Important constants
419 *
420  badmm = .false.
421  badnn = .false.
422  mmax = 1
423  nmax = 1
424  mnmax = 1
425  DO 10 j = 1, nsizes
426  mmax = max( mmax, mval( j ) )
427  IF( mval( j ).LT.0 )
428  $ badmm = .true.
429  nmax = max( nmax, nval( j ) )
430  IF( nval( j ).LT.0 )
431  $ badnn = .true.
432  mnmax = max( mnmax, min( mval( j ), nval( j ) ) )
433  10 CONTINUE
434 *
435  badnnb = .false.
436  kmax = 0
437  DO 20 j = 1, nwdths
438  kmax = max( kmax, kk( j ) )
439  IF( kk( j ).LT.0 )
440  $ badnnb = .true.
441  20 CONTINUE
442 *
443 * Check for errors
444 *
445  IF( nsizes.LT.0 ) THEN
446  info = -1
447  ELSE IF( badmm ) THEN
448  info = -2
449  ELSE IF( badnn ) THEN
450  info = -3
451  ELSE IF( nwdths.LT.0 ) THEN
452  info = -4
453  ELSE IF( badnnb ) THEN
454  info = -5
455  ELSE IF( ntypes.LT.0 ) THEN
456  info = -6
457  ELSE IF( nrhs.LT.0 ) THEN
458  info = -8
459  ELSE IF( lda.LT.nmax ) THEN
460  info = -13
461  ELSE IF( ldab.LT.2*kmax+1 ) THEN
462  info = -15
463  ELSE IF( ldq.LT.nmax ) THEN
464  info = -19
465  ELSE IF( ldp.LT.nmax ) THEN
466  info = -21
467  ELSE IF( ldc.LT.nmax ) THEN
468  info = -23
469  ELSE IF( ( max( lda, nmax )+1 )*nmax.GT.lwork ) THEN
470  info = -26
471  END IF
472 *
473  IF( info.NE.0 ) THEN
474  CALL xerbla( 'DCHKBB', -info )
475  RETURN
476  END IF
477 *
478 * Quick return if possible
479 *
480  IF( nsizes.EQ.0 .OR. ntypes.EQ.0 .OR. nwdths.EQ.0 )
481  $ RETURN
482 *
483 * More Important constants
484 *
485  unfl = dlamch( 'Safe minimum' )
486  ovfl = one / unfl
487  ulp = dlamch( 'Epsilon' )*dlamch( 'Base' )
488  ulpinv = one / ulp
489  rtunfl = sqrt( unfl )
490  rtovfl = sqrt( ovfl )
491 *
492 * Loop over sizes, widths, types
493 *
494  nerrs = 0
495  nmats = 0
496 *
497  DO 160 jsize = 1, nsizes
498  m = mval( jsize )
499  n = nval( jsize )
500  mnmin = min( m, n )
501  amninv = one / dble( max( 1, m, n ) )
502 *
503  DO 150 jwidth = 1, nwdths
504  k = kk( jwidth )
505  IF( k.GE.m .AND. k.GE.n )
506  $ GO TO 150
507  kl = max( 0, min( m-1, k ) )
508  ku = max( 0, min( n-1, k ) )
509 *
510  IF( nsizes.NE.1 ) THEN
511  mtypes = min( maxtyp, ntypes )
512  ELSE
513  mtypes = min( maxtyp+1, ntypes )
514  END IF
515 *
516  DO 140 jtype = 1, mtypes
517  IF( .NOT.dotype( jtype ) )
518  $ GO TO 140
519  nmats = nmats + 1
520  ntest = 0
521 *
522  DO 30 j = 1, 4
523  ioldsd( j ) = iseed( j )
524  30 CONTINUE
525 *
526 * Compute "A".
527 *
528 * Control parameters:
529 *
530 * KMAGN KMODE KTYPE
531 * =1 O(1) clustered 1 zero
532 * =2 large clustered 2 identity
533 * =3 small exponential (none)
534 * =4 arithmetic diagonal, (w/ singular values)
535 * =5 random log (none)
536 * =6 random nonhermitian, w/ singular values
537 * =7 (none)
538 * =8 (none)
539 * =9 random nonhermitian
540 *
541  IF( mtypes.GT.maxtyp )
542  $ GO TO 90
543 *
544  itype = ktype( jtype )
545  imode = kmode( jtype )
546 *
547 * Compute norm
548 *
549  GO TO ( 40, 50, 60 )kmagn( jtype )
550 *
551  40 CONTINUE
552  anorm = one
553  GO TO 70
554 *
555  50 CONTINUE
556  anorm = ( rtovfl*ulp )*amninv
557  GO TO 70
558 *
559  60 CONTINUE
560  anorm = rtunfl*max( m, n )*ulpinv
561  GO TO 70
562 *
563  70 CONTINUE
564 *
565  CALL dlaset( 'Full', lda, n, zero, zero, a, lda )
566  CALL dlaset( 'Full', ldab, n, zero, zero, ab, ldab )
567  iinfo = 0
568  cond = ulpinv
569 *
570 * Special Matrices -- Identity & Jordan block
571 *
572 * Zero
573 *
574  IF( itype.EQ.1 ) THEN
575  iinfo = 0
576 *
577  ELSE IF( itype.EQ.2 ) THEN
578 *
579 * Identity
580 *
581  DO 80 jcol = 1, n
582  a( jcol, jcol ) = anorm
583  80 CONTINUE
584 *
585  ELSE IF( itype.EQ.4 ) THEN
586 *
587 * Diagonal Matrix, singular values specified
588 *
589  CALL dlatms( m, n, 'S', iseed, 'N', work, imode, cond,
590  $ anorm, 0, 0, 'N', a, lda, work( m+1 ),
591  $ iinfo )
592 *
593  ELSE IF( itype.EQ.6 ) THEN
594 *
595 * Nonhermitian, singular values specified
596 *
597  CALL dlatms( m, n, 'S', iseed, 'N', work, imode, cond,
598  $ anorm, kl, ku, 'N', a, lda, work( m+1 ),
599  $ iinfo )
600 *
601  ELSE IF( itype.EQ.9 ) THEN
602 *
603 * Nonhermitian, random entries
604 *
605  CALL dlatmr( m, n, 'S', iseed, 'N', work, 6, one, one,
606  $ 'T', 'N', work( n+1 ), 1, one,
607  $ work( 2*n+1 ), 1, one, 'N', idumma, kl,
608  $ ku, zero, anorm, 'N', a, lda, idumma,
609  $ iinfo )
610 *
611  ELSE
612 *
613  iinfo = 1
614  END IF
615 *
616 * Generate Right-Hand Side
617 *
618  CALL dlatmr( m, nrhs, 'S', iseed, 'N', work, 6, one, one,
619  $ 'T', 'N', work( m+1 ), 1, one,
620  $ work( 2*m+1 ), 1, one, 'N', idumma, m, nrhs,
621  $ zero, one, 'NO', c, ldc, idumma, iinfo )
622 *
623  IF( iinfo.NE.0 ) THEN
624  WRITE( nounit, fmt = 9999 )'Generator', iinfo, n,
625  $ jtype, ioldsd
626  info = abs( iinfo )
627  RETURN
628  END IF
629 *
630  90 CONTINUE
631 *
632 * Copy A to band storage.
633 *
634  DO 110 j = 1, n
635  DO 100 i = max( 1, j-ku ), min( m, j+kl )
636  ab( ku+1+i-j, j ) = a( i, j )
637  100 CONTINUE
638  110 CONTINUE
639 *
640 * Copy C
641 *
642  CALL dlacpy( 'Full', m, nrhs, c, ldc, cc, ldc )
643 *
644 * Call DGBBRD to compute B, Q and P, and to update C.
645 *
646  CALL dgbbrd( 'B', m, n, nrhs, kl, ku, ab, ldab, bd, be,
647  $ q, ldq, p, ldp, cc, ldc, work, iinfo )
648 *
649  IF( iinfo.NE.0 ) THEN
650  WRITE( nounit, fmt = 9999 )'DGBBRD', iinfo, n, jtype,
651  $ ioldsd
652  info = abs( iinfo )
653  IF( iinfo.LT.0 ) THEN
654  RETURN
655  ELSE
656  result( 1 ) = ulpinv
657  GO TO 120
658  END IF
659  END IF
660 *
661 * Test 1: Check the decomposition A := Q * B * P'
662 * 2: Check the orthogonality of Q
663 * 3: Check the orthogonality of P
664 * 4: Check the computation of Q' * C
665 *
666  CALL dbdt01( m, n, -1, a, lda, q, ldq, bd, be, p, ldp,
667  $ work, result( 1 ) )
668  CALL dort01( 'Columns', m, m, q, ldq, work, lwork,
669  $ result( 2 ) )
670  CALL dort01( 'Rows', n, n, p, ldp, work, lwork,
671  $ result( 3 ) )
672  CALL dbdt02( m, nrhs, c, ldc, cc, ldc, q, ldq, work,
673  $ result( 4 ) )
674 *
675 * End of Loop -- Check for RESULT(j) > THRESH
676 *
677  ntest = 4
678  120 CONTINUE
679  ntestt = ntestt + ntest
680 *
681 * Print out tests which fail.
682 *
683  DO 130 jr = 1, ntest
684  IF( result( jr ).GE.thresh ) THEN
685  IF( nerrs.EQ.0 )
686  $ CALL dlahd2( nounit, 'DBB' )
687  nerrs = nerrs + 1
688  WRITE( nounit, fmt = 9998 )m, n, k, ioldsd, jtype,
689  $ jr, result( jr )
690  END IF
691  130 CONTINUE
692 *
693  140 CONTINUE
694  150 CONTINUE
695  160 CONTINUE
696 *
697 * Summary
698 *
699  CALL dlasum( 'DBB', nounit, nerrs, ntestt )
700  RETURN
701 *
702  9999 FORMAT( ' DCHKBB: ', a, ' returned INFO=', i5, '.', / 9x, 'M=',
703  $ i5, ' N=', i5, ' K=', i5, ', JTYPE=', i5, ', ISEED=(',
704  $ 3( i5, ',' ), i5, ')' )
705  9998 FORMAT( ' M =', i4, ' N=', i4, ', K=', i3, ', seed=',
706  $ 4( i4, ',' ), ' type ', i2, ', test(', i2, ')=', g10.3 )
707 *
708 * End of DCHKBB
709 *
710  END
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
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
subroutine xerbla(SRNAME, INFO)
XERBLA
Definition: xerbla.f:60
subroutine dlasum(TYPE, IOUNIT, IE, NRUN)
DLASUM
Definition: dlasum.f:43
subroutine dbdt01(M, N, KD, A, LDA, Q, LDQ, D, E, PT, LDPT, WORK, RESID)
DBDT01
Definition: dbdt01.f:141
subroutine dbdt02(M, N, B, LDB, C, LDC, U, LDU, WORK, RESID)
DBDT02
Definition: dbdt02.f:112
subroutine dort01(ROWCOL, M, N, U, LDU, WORK, LWORK, RESID)
DORT01
Definition: dort01.f:116
subroutine dchkbb(NSIZES, MVAL, NVAL, NWDTHS, KK, NTYPES, DOTYPE, NRHS, ISEED, THRESH, NOUNIT, A, LDA, AB, LDAB, BD, BE, Q, LDQ, P, LDP, C, LDC, CC, WORK, LWORK, RESULT, INFO)
DCHKBB
Definition: dchkbb.f:355
subroutine dlahd2(IOUNIT, PATH)
DLAHD2
Definition: dlahd2.f:65
subroutine dlatmr(M, N, DIST, ISEED, SYM, D, MODE, COND, DMAX, RSIGN, GRADE, DL, MODEL, CONDL, DR, MODER, CONDR, PIVTNG, IPIVOT, KL, KU, SPARSE, ANORM, PACK, A, LDA, IWORK, INFO)
DLATMR
Definition: dlatmr.f:471
subroutine dlatms(M, N, DIST, ISEED, SYM, D, MODE, COND, DMAX, KL, KU, PACK, A, LDA, WORK, INFO)
DLATMS
Definition: dlatms.f:321
subroutine dgbbrd(VECT, M, N, NCC, KL, KU, AB, LDAB, D, E, Q, LDQ, PT, LDPT, C, LDC, WORK, INFO)
DGBBRD
Definition: dgbbrd.f:187