1       SUBROUTINE SDRVGG( NSIZES, NN, NTYPES, DOTYPE, ISEED, THRESH,
  2      $                   THRSHN, NOUNIT, A, LDA, B, S, T, S2, T2, Q,
  3      $                   LDQ, Z, ALPHR1, ALPHI1, BETA1, ALPHR2, ALPHI2,
  4      $                   BETA2, VL, VR, WORK, LWORK, RESULT, INFO )
  5 *
  6 *  -- LAPACK test routine (version 3.1) --
  7 *     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
  8 *     November 2006
  9 *
 10 *     .. Scalar Arguments ..
 11       INTEGER            INFO, LDA, LDQ, LWORK, NOUNIT, NSIZES, NTYPES
 12       REAL               THRESH, THRSHN
 13 *     ..
 14 *     .. Array Arguments ..
 15       LOGICAL            DOTYPE( * )
 16       INTEGER            ISEED( 4 ), NN( * )
 17       REAL               A( LDA, * ), ALPHI1( * ), ALPHI2( * ),
 18      $                   ALPHR1( * ), ALPHR2( * ), B( LDA, * ),
 19      $                   BETA1( * ), BETA2( * ), Q( LDQ, * ),
 20      $                   RESULT* ), S( LDA, * ), S2( LDA, * ),
 21      $                   T( LDA, * ), T2( LDA, * ), VL( LDQ, * ),
 22      $                   VR( LDQ, * ), WORK( * ), Z( LDQ, * )
 23 *     ..
 24 *
 25 *  Purpose
 26 *  =======
 27 *
 28 *  SDRVGG  checks the nonsymmetric generalized eigenvalue driver
 29 *  routines.
 30 *                                T          T        T
 31 *  SGEGS factors A and B as Q S Z  and Q T Z , where   means
 32 *  transpose, T is upper triangular, S is in generalized Schur form
 33 *  (block upper triangular, with 1x1 and 2x2 blocks on the diagonal,
 34 *  the 2x2 blocks corresponding to complex conjugate pairs of
 35 *  generalized eigenvalues), and Q and Z are orthogonal.  It also
 36 *  computes the generalized eigenvalues (alpha(1),beta(1)), ...,
 37 *  (alpha(n),beta(n)), where alpha(j)=S(j,j) and beta(j)=P(j,j) --
 38 *  thus, w(j) = alpha(j)/beta(j) is a root of the generalized
 39 *  eigenvalue problem
 40 *
 41 *      det( A - w(j) B ) = 0
 42 *
 43 *  and m(j) = beta(j)/alpha(j) is a root of the essentially equivalent
 44 *  problem
 45 *
 46 *      det( m(j) A - B ) = 0
 47 *
 48 *  SGEGV computes the generalized eigenvalues (alpha(1),beta(1)), ...,
 49 *  (alpha(n),beta(n)), the matrix L whose columns contain the
 50 *  generalized left eigenvectors l, and the matrix R whose columns
 51 *  contain the generalized right eigenvectors r for the pair (A,B).
 52 *
 53 *  When SDRVGG is called, a number of matrix "sizes" ("n's") and a
 54 *  number of matrix "types" are specified.  For each size ("n")
 55 *  and each type of matrix, one matrix will be generated and used
 56 *  to test the nonsymmetric eigenroutines.  For each matrix, 7
 57 *  tests will be performed and compared with the threshhold THRESH:
 58 *
 59 *  Results from SGEGS:
 60 *
 61 *                   T
 62 *  (1)   | A - Q S Z  | / ( |A| n ulp )
 63 *
 64 *                   T
 65 *  (2)   | B - Q T Z  | / ( |B| n ulp )
 66 *
 67 *                T
 68 *  (3)   | I - QQ  | / ( n ulp )
 69 *
 70 *                T
 71 *  (4)   | I - ZZ  | / ( n ulp )
 72 *
 73 *  (5)   maximum over j of D(j)  where:
 74 *
 75 *  if alpha(j) is real:
 76 *                      |alpha(j) - S(j,j)|        |beta(j) - T(j,j)|
 77 *            D(j) = ------------------------ + -----------------------
 78 *                   max(|alpha(j)|,|S(j,j)|)   max(|beta(j)|,|T(j,j)|)
 79 *
 80 *  if alpha(j) is complex:
 81 *                                  | det( s S - w T ) |
 82 *            D(j) = ---------------------------------------------------
 83 *                   ulp max( s norm(S), |w| norm(T) )*norm( s S - w T )
 84 *
 85 *            and S and T are here the 2 x 2 diagonal blocks of S and T
 86 *            corresponding to the j-th eigenvalue.
 87 *
 88 *  Results from SGEGV:
 89 *
 90 *  (6)   max over all left eigenvalue/-vector pairs (beta/alpha,l) of
 91 *
 92 *     | l**H * (beta A - alpha B) | / ( ulp max( |beta A|, |alpha B| ) )
 93 *
 94 *        where l**H is the conjugate tranpose of l.
 95 *
 96 *  (7)   max over all right eigenvalue/-vector pairs (beta/alpha,r) of
 97 *
 98 *        | (beta A - alpha B) r | / ( ulp max( |beta A|, |alpha B| ) )
 99 *
100 *  Test Matrices
101 *  ---- --------
102 *
103 *  The sizes of the test matrices are specified by an array
104 *  NN(1:NSIZES); the value of each element NN(j) specifies one size.
105 *  The "types" are specified by a logical array DOTYPE( 1:NTYPES ); if
106 *  DOTYPE(j) is .TRUE., then matrix type "j" will be generated.
107 *  Currently, the list of possible types is:
108 *
109 *  (1)  ( 0, 0 )         (a pair of zero matrices)
110 *
111 *  (2)  ( I, 0 )         (an identity and a zero matrix)
112 *
113 *  (3)  ( 0, I )         (an identity and a zero matrix)
114 *
115 *  (4)  ( I, I )         (a pair of identity matrices)
116 *
117 *          t   t
118 *  (5)  ( J , J  )       (a pair of transposed Jordan blocks)
119 *
120 *                                      t                ( I   0  )
121 *  (6)  ( X, Y )         where  X = ( J   0  )  and Y = (      t )
122 *                                   ( 0   I  )          ( 0   J  )
123 *                        and I is a k x k identity and J a (k+1)x(k+1)
124 *                        Jordan block; k=(N-1)/2
125 *
126 *  (7)  ( D, I )         where D is diag( 0, 1,..., N-1 ) (a diagonal
127 *                        matrix with those diagonal entries.)
128 *  (8)  ( I, D )
129 *
130 *  (9)  ( big*D, small*I ) where "big" is near overflow and small=1/big
131 *
132 *  (10) ( small*D, big*I )
133 *
134 *  (11) ( big*I, small*D )
135 *
136 *  (12) ( small*I, big*D )
137 *
138 *  (13) ( big*D, big*I )
139 *
140 *  (14) ( small*D, small*I )
141 *
142 *  (15) ( D1, D2 )        where D1 is diag( 0, 0, 1, ..., N-3, 0 ) and
143 *                         D2 is diag( 0, N-3, N-4,..., 1, 0, 0 )
144 *            t   t
145 *  (16) Q ( J , J ) Z     where Q and Z are random orthogonal matrices.
146 *
147 *  (17) Q ( T1, T2 ) Z    where T1 and T2 are upper triangular matrices
148 *                         with random O(1) entries above the diagonal
149 *                         and diagonal entries diag(T1) =
150 *                         ( 0, 0, 1, ..., N-3, 0 ) and diag(T2) =
151 *                         ( 0, N-3, N-4,..., 1, 0, 0 )
152 *
153 *  (18) Q ( T1, T2 ) Z    diag(T1) = ( 0, 0, 1, 1, s, ..., s, 0 )
154 *                         diag(T2) = ( 0, 1, 0, 1,..., 1, 0 )
155 *                         s = machine precision.
156 *
157 *  (19) Q ( T1, T2 ) Z    diag(T1)=( 0,0,1,1, 1-d, ..., 1-(N-5)*d=s, 0 )
158 *                         diag(T2) = ( 0, 1, 0, 1, ..., 1, 0 )
159 *
160 *                                                         N-5
161 *  (20) Q ( T1, T2 ) Z    diag(T1)=( 0, 0, 1, 1, a, ..., a   =s, 0 )
162 *                         diag(T2) = ( 0, 1, 0, 1, ..., 1, 0, 0 )
163 *
164 *  (21) Q ( T1, T2 ) Z    diag(T1)=( 0, 0, 1, r1, r2, ..., r(N-4), 0 )
165 *                         diag(T2) = ( 0, 1, 0, 1, ..., 1, 0, 0 )
166 *                         where r1,..., r(N-4) are random.
167 *
168 *  (22) Q ( big*T1, small*T2 ) Z    diag(T1) = ( 0, 0, 1, ..., N-3, 0 )
169 *                                   diag(T2) = ( 0, 1, ..., 1, 0, 0 )
170 *
171 *  (23) Q ( small*T1, big*T2 ) Z    diag(T1) = ( 0, 0, 1, ..., N-3, 0 )
172 *                                   diag(T2) = ( 0, 1, ..., 1, 0, 0 )
173 *
174 *  (24) Q ( small*T1, small*T2 ) Z  diag(T1) = ( 0, 0, 1, ..., N-3, 0 )
175 *                                   diag(T2) = ( 0, 1, ..., 1, 0, 0 )
176 *
177 *  (25) Q ( big*T1, big*T2 ) Z      diag(T1) = ( 0, 0, 1, ..., N-3, 0 )
178 *                                   diag(T2) = ( 0, 1, ..., 1, 0, 0 )
179 *
180 *  (26) Q ( T1, T2 ) Z     where T1 and T2 are random upper-triangular
181 *                          matrices.
182 *
183 *  Arguments
184 *  =========
185 *
186 *  NSIZES  (input) INTEGER
187 *          The number of sizes of matrices to use.  If it is zero,
188 *          SDRVGG does nothing.  It must be at least zero.
189 *
190 *  NN      (input) INTEGER array, dimension (NSIZES)
191 *          An array containing the sizes to be used for the matrices.
192 *          Zero values will be skipped.  The values must be at least
193 *          zero.
194 *
195 *  NTYPES  (input) INTEGER
196 *          The number of elements in DOTYPE.   If it is zero, SDRVGG
197 *          does nothing.  It must be at least zero.  If it is MAXTYP+1
198 *          and NSIZES is 1, then an additional type, MAXTYP+1 is
199 *          defined, which is to use whatever matrix is in A.  This
200 *          is only useful if DOTYPE(1:MAXTYP) is .FALSE. and
201 *          DOTYPE(MAXTYP+1) is .TRUE. .
202 *
203 *  DOTYPE  (input) LOGICAL array, dimension (NTYPES)
204 *          If DOTYPE(j) is .TRUE., then for each size in NN a
205 *          matrix of that size and of type j will be generated.
206 *          If NTYPES is smaller than the maximum number of types
207 *          defined (PARAMETER MAXTYP), then types NTYPES+1 through
208 *          MAXTYP will not be generated.  If NTYPES is larger
209 *          than MAXTYP, DOTYPE(MAXTYP+1) through DOTYPE(NTYPES)
210 *          will be ignored.
211 *
212 *  ISEED   (input/output) INTEGER array, dimension (4)
213 *          On entry ISEED specifies the seed of the random number
214 *          generator. The array elements should be between 0 and 4095;
215 *          if not they will be reduced mod 4096.  Also, ISEED(4) must
216 *          be odd.  The random number generator uses a linear
217 *          congruential sequence limited to small integers, and so
218 *          should produce machine independent random numbers. The
219 *          values of ISEED are changed on exit, and can be used in the
220 *          next call to SDRVGG to continue the same random number
221 *          sequence.
222 *
223 *  THRESH  (input) REAL
224 *          A test will count as "failed" if the "error", computed as
225 *          described above, exceeds THRESH.  Note that the error is
226 *          scaled to be O(1), so THRESH should be a reasonably small
227 *          multiple of 1, e.g., 10 or 100.  In particular, it should
228 *          not depend on the precision (single vs. double) or the size
229 *          of the matrix.  It must be at least zero.
230 *
231 *  THRSHN  (input) REAL
232 *          Threshhold for reporting eigenvector normalization error.
233 *          If the normalization of any eigenvector differs from 1 by
234 *          more than THRSHN*ulp, then a special error message will be
235 *          printed.  (This is handled separately from the other tests,
236 *          since only a compiler or programming error should cause an
237 *          error message, at least if THRSHN is at least 5--10.)
238 *
239 *  NOUNIT  (input) INTEGER
240 *          The FORTRAN unit number for printing out error messages
241 *          (e.g., if a routine returns IINFO not equal to 0.)
242 *
243 *  A       (input/workspace) REAL array, dimension
244 *                            (LDA, max(NN))
245 *          Used to hold the original A matrix.  Used as input only
246 *          if NTYPES=MAXTYP+1, DOTYPE(1:MAXTYP)=.FALSE., and
247 *          DOTYPE(MAXTYP+1)=.TRUE.
248 *
249 *  LDA     (input) INTEGER
250 *          The leading dimension of A, B, S, T, S2, and T2.
251 *          It must be at least 1 and at least max( NN ).
252 *
253 *  B       (input/workspace) REAL array, dimension
254 *                            (LDA, max(NN))
255 *          Used to hold the original B matrix.  Used as input only
256 *          if NTYPES=MAXTYP+1, DOTYPE(1:MAXTYP)=.FALSE., and
257 *          DOTYPE(MAXTYP+1)=.TRUE.
258 *
259 *  S       (workspace) REAL array, dimension (LDA, max(NN))
260 *          The Schur form matrix computed from A by SGEGS.  On exit, S
261 *          contains the Schur form matrix corresponding to the matrix
262 *          in A.
263 *
264 *  T       (workspace) REAL array, dimension (LDA, max(NN))
265 *          The upper triangular matrix computed from B by SGEGS.
266 *
267 *  S2      (workspace) REAL array, dimension (LDA, max(NN))
268 *          The matrix computed from A by SGEGV.  This will be the
269 *          Schur form of some matrix related to A, but will not, in
270 *          general, be the same as S.
271 *
272 *  T2      (workspace) REAL array, dimension (LDA, max(NN))
273 *          The matrix computed from B by SGEGV.  This will be the
274 *          Schur form of some matrix related to B, but will not, in
275 *          general, be the same as T.
276 *
277 *  Q       (workspace) REAL array, dimension (LDQ, max(NN))
278 *          The (left) orthogonal matrix computed by SGEGS.
279 *
280 *  LDQ     (input) INTEGER
281 *          The leading dimension of Q, Z, VL, and VR.  It must
282 *          be at least 1 and at least max( NN ).
283 *
284 *  Z       (workspace) REAL array of
285 *                             dimension( LDQ, max(NN) )
286 *          The (right) orthogonal matrix computed by SGEGS.
287 *
288 *  ALPHR1  (workspace) REAL array, dimension (max(NN))
289 *  ALPHI1  (workspace) REAL array, dimension (max(NN))
290 *  BETA1   (workspace) REAL array, dimension (max(NN))
291 *
292 *          The generalized eigenvalues of (A,B) computed by SGEGS.
293 *          ( ALPHR1(k)+ALPHI1(k)*i ) / BETA1(k) is the k-th
294 *          generalized eigenvalue of the matrices in A and B.
295 *
296 *  ALPHR2  (workspace) REAL array, dimension (max(NN))
297 *  ALPHI2  (workspace) REAL array, dimension (max(NN))
298 *  BETA2   (workspace) REAL array, dimension (max(NN))
299 *
300 *          The generalized eigenvalues of (A,B) computed by SGEGV.
301 *          ( ALPHR2(k)+ALPHI2(k)*i ) / BETA2(k) is the k-th
302 *          generalized eigenvalue of the matrices in A and B.
303 *
304 *  VL      (workspace) REAL array, dimension (LDQ, max(NN))
305 *          The (block lower triangular) left eigenvector matrix for
306 *          the matrices in A and B.  (See STGEVC for the format.)
307 *
308 *  VR      (workspace) REAL array, dimension (LDQ, max(NN))
309 *          The (block upper triangular) right eigenvector matrix for
310 *          the matrices in A and B.  (See STGEVC for the format.)
311 *
312 *  WORK    (workspace) REAL array, dimension (LWORK)
313 *
314 *  LWORK   (input) INTEGER
315 *          The number of entries in WORK.  This must be at least
316 *          2*N + MAX( 6*N, N*(NB+1), (k+1)*(2*k+N+1) ), where
317 *          "k" is the sum of the blocksize and number-of-shifts for
318 *          SHGEQZ, and NB is the greatest of the blocksizes for
319 *          SGEQRF, SORMQR, and SORGQR.  (The blocksizes and the
320 *          number-of-shifts are retrieved through calls to ILAENV.)
321 *
322 *  RESULT  (output) REAL array, dimension (15)
323 *          The values computed by the tests described above.
324 *          The values are currently limited to 1/ulp, to avoid
325 *          overflow.
326 *
327 *  INFO    (output) INTEGER
328 *          = 0:  successful exit
329 *          < 0:  if INFO = -i, the i-th argument had an illegal value.
330 *          > 0:  A routine returned an error code.  INFO is the
331 *                absolute value of the INFO value returned.
332 *
333 *  =====================================================================
334 *
335 *     .. Parameters ..
336       REAL               ZERO, ONE
337       PARAMETER          ( ZERO = 0.0, ONE = 1.0 )
338       INTEGER            MAXTYP
339       PARAMETER          ( MAXTYP = 26 )
340 *     ..
341 *     .. Local Scalars ..
342       LOGICAL            BADNN, ILABAD
343       INTEGER            I1, IADD, IINFO, IN, J, JC, JR, JSIZE, JTYPE,
344      $                   LWKOPT, MTYPES, N, N1, NB, NBZ, NERRS, NMATS,
345      $                   NMAX, NS, NTEST, NTESTT
346       REAL               SAFMAX, SAFMIN, TEMP1, TEMP2, ULP, ULPINV
347 *     ..
348 *     .. Local Arrays ..
349       INTEGER            IASIGN( MAXTYP ), IBSIGN( MAXTYP ),
350      $                   IOLDSD( 4 ), KADD( 6 ), KAMAGN( MAXTYP ),
351      $                   KATYPE( MAXTYP ), KAZERO( MAXTYP ),
352      $                   KBMAGN( MAXTYP ), KBTYPE( MAXTYP ),
353      $                   KBZERO( MAXTYP ), KCLASS( MAXTYP ),
354      $                   KTRIAN( MAXTYP ), KZ1( 6 ), KZ2( 6 )
355       REAL               DUMMA( 4 ), RMAGN( 03 )
356 *     ..
357 *     .. External Functions ..
358       INTEGER            ILAENV
359       REAL               SLAMCH, SLARND
360       EXTERNAL           ILAENV, SLAMCH, SLARND
361 *     ..
362 *     .. External Subroutines ..
363       EXTERNAL           ALASVM, SGEGS, SGEGV, SGET51, SGET52, SGET53,
364      $                   SLABAD, SLACPY, SLARFG, SLASET, SLATM4, SORM2R,
365      $                   XERBLA
366 *     ..
367 *     .. Intrinsic Functions ..
368       INTRINSIC          ABSMAXMIN, REAL, SIGN
369 *     ..
370 *     .. Data statements ..
371       DATA               KCLASS / 15*110*21*3 /
372       DATA               KZ1 / 012133 /
373       DATA               KZ2 / 001211 /
374       DATA               KADD / 000032 /
375       DATA               KATYPE / 0101234144114,
376      $                   442458794*40 /
377       DATA               KBTYPE / 00112-3141144,
378      $                   11-42-48*80 /
379       DATA               KAZERO / 6*1212*22*12*2313,
380      $                   4*54*31 /
381       DATA               KBZERO / 6*1122*12*22*1414,
382      $                   4*64*41 /
383       DATA               KAMAGN / 8*12323237*1233,
384      $                   21 /
385       DATA               KBMAGN / 8*13232237*1323,
386      $                   21 /
387       DATA               KTRIAN / 16*010*1 /
388       DATA               IASIGN / 6*0202*22*03*2023*0,
389      $                   5*20 /
390       DATA               IBSIGN / 7*022*02*22*02029*0 /
391 *     ..
392 *     .. Executable Statements ..
393 *
394 *     Check for errors
395 *
396       INFO = 0
397 *
398       BADNN = .FALSE.
399       NMAX = 1
400       DO 10 J = 1, NSIZES
401          NMAX = MAX( NMAX, NN( J ) )
402          IF( NN( J ).LT.0 )
403      $      BADNN = .TRUE.
404    10 CONTINUE
405 *
406 *     Maximum blocksize and shift -- we assume that blocksize and number
407 *     of shifts are monotone increasing functions of N.
408 *
409       NB = MAX1, ILAENV( 1'SGEQRF'' ', NMAX, NMAX, -1-1 ),
410      $     ILAENV( 1'SORMQR''LT', NMAX, NMAX, NMAX, -1 ),
411      $     ILAENV( 1'SORGQR'' ', NMAX, NMAX, NMAX, -1 ) )
412       NBZ = ILAENV( 1'SHGEQZ''SII', NMAX, 1, NMAX, 0 )
413       NS = ILAENV( 4'SHGEQZ''SII', NMAX, 1, NMAX, 0 )
414       I1 = NBZ + NS
415       LWKOPT = 2*NMAX + MAX6*NMAX, NMAX*( NB+1 ),
416      $         ( 2*I1+NMAX+1 )*( I1+1 ) )
417 *
418 *     Check for errors
419 *
420       IF( NSIZES.LT.0 ) THEN
421          INFO = -1
422       ELSE IF( BADNN ) THEN
423          INFO = -2
424       ELSE IF( NTYPES.LT.0 ) THEN
425          INFO = -3
426       ELSE IF( THRESH.LT.ZERO ) THEN
427          INFO = -6
428       ELSE IF( LDA.LE.1 .OR. LDA.LT.NMAX ) THEN
429          INFO = -10
430       ELSE IF( LDQ.LE.1 .OR. LDQ.LT.NMAX ) THEN
431          INFO = -19
432       ELSE IF( LWKOPT.GT.LWORK ) THEN
433          INFO = -30
434       END IF
435 *
436       IF( INFO.NE.0 ) THEN
437          CALL XERBLA( 'SDRVGG'-INFO )
438          RETURN
439       END IF
440 *
441 *     Quick return if possible
442 *
443       IF( NSIZES.EQ.0 .OR. NTYPES.EQ.0 )
444      $   RETURN
445 *
446       SAFMIN = SLAMCH( 'Safe minimum' )
447       ULP = SLAMCH( 'Epsilon' )*SLAMCH( 'Base' )
448       SAFMIN = SAFMIN / ULP
449       SAFMAX = ONE / SAFMIN
450       CALL SLABAD( SAFMIN, SAFMAX )
451       ULPINV = ONE / ULP
452 *
453 *     The values RMAGN(2:3) depend on N, see below.
454 *
455       RMAGN( 0 ) = ZERO
456       RMAGN( 1 ) = ONE
457 *
458 *     Loop over sizes, types
459 *
460       NTESTT = 0
461       NERRS = 0
462       NMATS = 0
463 *
464       DO 170 JSIZE = 1, NSIZES
465          N = NN( JSIZE )
466          N1 = MAX1, N )
467          RMAGN( 2 ) = SAFMAX*ULP / REAL( N1 )
468          RMAGN( 3 ) = SAFMIN*ULPINV*N1
469 *
470          IF( NSIZES.NE.1 ) THEN
471             MTYPES = MIN( MAXTYP, NTYPES )
472          ELSE
473             MTYPES = MIN( MAXTYP+1, NTYPES )
474          END IF
475 *
476          DO 160 JTYPE = 1, MTYPES
477             IF.NOT.DOTYPE( JTYPE ) )
478      $         GO TO 160
479             NMATS = NMATS + 1
480             NTEST = 0
481 *
482 *           Save ISEED in case of an error.
483 *
484             DO 20 J = 14
485                IOLDSD( J ) = ISEED( J )
486    20       CONTINUE
487 *
488 *           Initialize RESULT
489 *
490             DO 30 J = 115
491                RESULT( J ) = ZERO
492    30       CONTINUE
493 *
494 *           Compute A and B
495 *
496 *           Description of control parameters:
497 *
498 *           KCLASS: =1 means w/o rotation, =2 means w/ rotation,
499 *                   =3 means random.
500 *           KATYPE: the "type" to be passed to SLATM4 for computing A.
501 *           KAZERO: the pattern of zeros on the diagonal for A:
502 *                   =1: ( xxx ), =2: (0, xxx ) =3: ( 0, 0, xxx, 0 ),
503 *                   =4: ( 0, xxx, 0, 0 ), =5: ( 0, 0, 1, xxx, 0 ),
504 *                   =6: ( 0, 1, 0, xxx, 0 ).  (xxx means a string of
505 *                   non-zero entries.)
506 *           KAMAGN: the magnitude of the matrix: =0: zero, =1: O(1),
507 *                   =2: large, =3: small.
508 *           IASIGN: 1 if the diagonal elements of A are to be
509 *                   multiplied by a random magnitude 1 number, =2 if
510 *                   randomly chosen diagonal blocks are to be rotated
511 *                   to form 2x2 blocks.
512 *           KBTYPE, KBZERO, KBMAGN, IBSIGN: the same, but for B.
513 *           KTRIAN: =0: don't fill in the upper triangle, =1: do.
514 *           KZ1, KZ2, KADD: used to implement KAZERO and KBZERO.
515 *           RMAGN: used to implement KAMAGN and KBMAGN.
516 *
517             IF( MTYPES.GT.MAXTYP )
518      $         GO TO 110
519             IINFO = 0
520             IF( KCLASS( JTYPE ).LT.3 ) THEN
521 *
522 *              Generate A (w/o rotation)
523 *
524                IFABS( KATYPE( JTYPE ) ).EQ.3 ) THEN
525                   IN = 2*( ( N-1 ) / 2 ) + 1
526                   IFIN.NE.N )
527      $               CALL SLASET( 'Full', N, N, ZERO, ZERO, A, LDA )
528                ELSE
529                   IN = N
530                END IF
531                CALL SLATM4( KATYPE( JTYPE ), IN, KZ1( KAZERO( JTYPE ) ),
532      $                      KZ2( KAZERO( JTYPE ) ), IASIGN( JTYPE ),
533      $                      RMAGN( KAMAGN( JTYPE ) ), ULP,
534      $                      RMAGN( KTRIAN( JTYPE )*KAMAGN( JTYPE ) ), 2,
535      $                      ISEED, A, LDA )
536                IADD = KADD( KAZERO( JTYPE ) )
537                IF( IADD.GT.0 .AND. IADD.LE.N )
538      $            A( IADD, IADD ) = ONE
539 *
540 *              Generate B (w/o rotation)
541 *
542                IFABS( KBTYPE( JTYPE ) ).EQ.3 ) THEN
543                   IN = 2*( ( N-1 ) / 2 ) + 1
544                   IFIN.NE.N )
545      $               CALL SLASET( 'Full', N, N, ZERO, ZERO, B, LDA )
546                ELSE
547                   IN = N
548                END IF
549                CALL SLATM4( KBTYPE( JTYPE ), IN, KZ1( KBZERO( JTYPE ) ),
550      $                      KZ2( KBZERO( JTYPE ) ), IBSIGN( JTYPE ),
551      $                      RMAGN( KBMAGN( JTYPE ) ), ONE,
552      $                      RMAGN( KTRIAN( JTYPE )*KBMAGN( JTYPE ) ), 2,
553      $                      ISEED, B, LDA )
554                IADD = KADD( KBZERO( JTYPE ) )
555                IF( IADD.NE.0 .AND. IADD.LE.N )
556      $            B( IADD, IADD ) = ONE
557 *
558                IF( KCLASS( JTYPE ).EQ.2 .AND. N.GT.0 ) THEN
559 *
560 *                 Include rotations
561 *
562 *                 Generate Q, Z as Householder transformations times
563 *                 a diagonal matrix.
564 *
565                   DO 50 JC = 1, N - 1
566                      DO 40 JR = JC, N
567                         Q( JR, JC ) = SLARND( 3, ISEED )
568                         Z( JR, JC ) = SLARND( 3, ISEED )
569    40                CONTINUE
570                      CALL SLARFG( N+1-JC, Q( JC, JC ), Q( JC+1, JC ), 1,
571      $                            WORK( JC ) )
572                      WORK( 2*N+JC ) = SIGN( ONE, Q( JC, JC ) )
573                      Q( JC, JC ) = ONE
574                      CALL SLARFG( N+1-JC, Z( JC, JC ), Z( JC+1, JC ), 1,
575      $                            WORK( N+JC ) )
576                      WORK( 3*N+JC ) = SIGN( ONE, Z( JC, JC ) )
577                      Z( JC, JC ) = ONE
578    50             CONTINUE
579                   Q( N, N ) = ONE
580                   WORK( N ) = ZERO
581                   WORK( 3*N ) = SIGN( ONE, SLARND( 2, ISEED ) )
582                   Z( N, N ) = ONE
583                   WORK( 2*N ) = ZERO
584                   WORK( 4*N ) = SIGN( ONE, SLARND( 2, ISEED ) )
585 *
586 *                 Apply the diagonal matrices
587 *
588                   DO 70 JC = 1, N
589                      DO 60 JR = 1, N
590                         A( JR, JC ) = WORK( 2*N+JR )*WORK( 3*N+JC )*
591      $                                A( JR, JC )
592                         B( JR, JC ) = WORK( 2*N+JR )*WORK( 3*N+JC )*
593      $                                B( JR, JC )
594    60                CONTINUE
595    70             CONTINUE
596                   CALL SORM2R( 'L''N', N, N, N-1, Q, LDQ, WORK, A,
597      $                         LDA, WORK( 2*N+1 ), IINFO )
598                   IF( IINFO.NE.0 )
599      $               GO TO 100
600                   CALL SORM2R( 'R''T', N, N, N-1, Z, LDQ, WORK( N+1 ),
601      $                         A, LDA, WORK( 2*N+1 ), IINFO )
602                   IF( IINFO.NE.0 )
603      $               GO TO 100
604                   CALL SORM2R( 'L''N', N, N, N-1, Q, LDQ, WORK, B,
605      $                         LDA, WORK( 2*N+1 ), IINFO )
606                   IF( IINFO.NE.0 )
607      $               GO TO 100
608                   CALL SORM2R( 'R''T', N, N, N-1, Z, LDQ, WORK( N+1 ),
609      $                         B, LDA, WORK( 2*N+1 ), IINFO )
610                   IF( IINFO.NE.0 )
611      $               GO TO 100
612                END IF
613             ELSE
614 *
615 *              Random matrices
616 *
617                DO 90 JC = 1, N
618                   DO 80 JR = 1, N
619                      A( JR, JC ) = RMAGN( KAMAGN( JTYPE ) )*
620      $                             SLARND( 2, ISEED )
621                      B( JR, JC ) = RMAGN( KBMAGN( JTYPE ) )*
622      $                             SLARND( 2, ISEED )
623    80             CONTINUE
624    90          CONTINUE
625             END IF
626 *
627   100       CONTINUE
628 *
629             IF( IINFO.NE.0 ) THEN
630                WRITE( NOUNIT, FMT = 9999 )'Generator', IINFO, N, JTYPE,
631      $            IOLDSD
632                INFO = ABS( IINFO )
633                RETURN
634             END IF
635 *
636   110       CONTINUE
637 *
638 *           Call SGEGS to compute H, T, Q, Z, alpha, and beta.
639 *
640             CALL SLACPY( ' ', N, N, A, LDA, S, LDA )
641             CALL SLACPY( ' ', N, N, B, LDA, T, LDA )
642             NTEST = 1
643             RESULT1 ) = ULPINV
644 *
645             CALL SGEGS( 'V''V', N, S, LDA, T, LDA, ALPHR1, ALPHI1,
646      $                  BETA1, Q, LDQ, Z, LDQ, WORK, LWORK, IINFO )
647             IF( IINFO.NE.0 ) THEN
648                WRITE( NOUNIT, FMT = 9999 )'SGEGS', IINFO, N, JTYPE,
649      $            IOLDSD
650                INFO = ABS( IINFO )
651                GO TO 140
652             END IF
653 *
654             NTEST = 4
655 *
656 *           Do tests 1--4
657 *
658             CALL SGET51( 1, N, A, LDA, S, LDA, Q, LDQ, Z, LDQ, WORK,
659      $                   RESULT1 ) )
660             CALL SGET51( 1, N, B, LDA, T, LDA, Q, LDQ, Z, LDQ, WORK,
661      $                   RESULT2 ) )
662             CALL SGET51( 3, N, B, LDA, T, LDA, Q, LDQ, Q, LDQ, WORK,
663      $                   RESULT3 ) )
664             CALL SGET51( 3, N, B, LDA, T, LDA, Z, LDQ, Z, LDQ, WORK,
665      $                   RESULT4 ) )
666 *
667 *           Do test 5: compare eigenvalues with diagonals.
668 *           Also check Schur form of A.
669 *
670             TEMP1 = ZERO
671 *
672             DO 120 J = 1, N
673                ILABAD = .FALSE.
674                IF( ALPHI1( J ).EQ.ZERO ) THEN
675                   TEMP2 = ( ABS( ALPHR1( J )-S( J, J ) ) /
676      $                    MAX( SAFMIN, ABS( ALPHR1( J ) ), ABS( S( J,
677      $                    J ) ) )+ABS( BETA1( J )-T( J, J ) ) /
678      $                    MAX( SAFMIN, ABS( BETA1( J ) ), ABS( T( J,
679      $                    J ) ) ) ) / ULP
680                   IF( J.LT.N ) THEN
681                      IF( S( J+1, J ).NE.ZERO )
682      $                  ILABAD = .TRUE.
683                   END IF
684                   IF( J.GT.1 ) THEN
685                      IF( S( J, J-1 ).NE.ZERO )
686      $                  ILABAD = .TRUE.
687                   END IF
688                ELSE
689                   IF( ALPHI1( J ).GT.ZERO ) THEN
690                      I1 = J
691                   ELSE
692                      I1 = J - 1
693                   END IF
694                   IF( I1.LE.0 .OR. I1.GE.N ) THEN
695                      ILABAD = .TRUE.
696                   ELSE IF( I1.LT.N-1 ) THEN
697                      IF( S( I1+2, I1+1 ).NE.ZERO )
698      $                  ILABAD = .TRUE.
699                   ELSE IF( I1.GT.1 ) THEN
700                      IF( S( I1, I1-1 ).NE.ZERO )
701      $                  ILABAD = .TRUE.
702                   END IF
703                   IF.NOT.ILABAD ) THEN
704                      CALL SGET53( S( I1, I1 ), LDA, T( I1, I1 ), LDA,
705      $                            BETA1( J ), ALPHR1( J ), ALPHI1( J ),
706      $                            TEMP2, IINFO )
707                      IF( IINFO.GE.3 ) THEN
708                         WRITE( NOUNIT, FMT = 9997 )IINFO, J, N, JTYPE,
709      $                     IOLDSD
710                         INFO = ABS( IINFO )
711                      END IF
712                   ELSE
713                      TEMP2 = ULPINV
714                   END IF
715                END IF
716                TEMP1 = MAX( TEMP1, TEMP2 )
717                IF( ILABAD ) THEN
718                   WRITE( NOUNIT, FMT = 9996 )J, N, JTYPE, IOLDSD
719                END IF
720   120       CONTINUE
721             RESULT5 ) = TEMP1
722 *
723 *           Call SGEGV to compute S2, T2, VL, and VR, do tests.
724 *
725 *           Eigenvalues and Eigenvectors
726 *
727             CALL SLACPY( ' ', N, N, A, LDA, S2, LDA )
728             CALL SLACPY( ' ', N, N, B, LDA, T2, LDA )
729             NTEST = 6
730             RESULT6 ) = ULPINV
731 *
732             CALL SGEGV( 'V''V', N, S2, LDA, T2, LDA, ALPHR2, ALPHI2,
733      $                  BETA2, VL, LDQ, VR, LDQ, WORK, LWORK, IINFO )
734             IF( IINFO.NE.0 ) THEN
735                WRITE( NOUNIT, FMT = 9999 )'SGEGV', IINFO, N, JTYPE,
736      $            IOLDSD
737                INFO = ABS( IINFO )
738                GO TO 140
739             END IF
740 *
741             NTEST = 7
742 *
743 *           Do Tests 6 and 7
744 *
745             CALL SGET52( .TRUE., N, A, LDA, B, LDA, VL, LDQ, ALPHR2,
746      $                   ALPHI2, BETA2, WORK, DUMMA( 1 ) )
747             RESULT6 ) = DUMMA( 1 )
748             IF( DUMMA( 2 ).GT.THRSHN ) THEN
749                WRITE( NOUNIT, FMT = 9998 )'Left''SGEGV', DUMMA( 2 ),
750      $            N, JTYPE, IOLDSD
751             END IF
752 *
753             CALL SGET52( .FALSE., N, A, LDA, B, LDA, VR, LDQ, ALPHR2,
754      $                   ALPHI2, BETA2, WORK, DUMMA( 1 ) )
755             RESULT7 ) = DUMMA( 1 )
756             IF( DUMMA( 2 ).GT.THRESH ) THEN
757                WRITE( NOUNIT, FMT = 9998 )'Right''SGEGV', DUMMA( 2 ),
758      $            N, JTYPE, IOLDSD
759             END IF
760 *
761 *           Check form of Complex eigenvalues.
762 *
763             DO 130 J = 1, N
764                ILABAD = .FALSE.
765                IF( ALPHI2( J ).GT.ZERO ) THEN
766                   IF( J.EQ.N ) THEN
767                      ILABAD = .TRUE.
768                   ELSE IF( ALPHI2( J+1 ).GE.ZERO ) THEN
769                      ILABAD = .TRUE.
770                   END IF
771                ELSE IF( ALPHI2( J ).LT.ZERO ) THEN
772                   IF( J.EQ.1 ) THEN
773                      ILABAD = .TRUE.
774                   ELSE IF( ALPHI2( J-1 ).LE.ZERO ) THEN
775                      ILABAD = .TRUE.
776                   END IF
777                END IF
778                IF( ILABAD ) THEN
779                   WRITE( NOUNIT, FMT = 9996 )J, N, JTYPE, IOLDSD
780                END IF
781   130       CONTINUE
782 *
783 *           End of Loop -- Check for RESULT(j) > THRESH
784 *
785   140       CONTINUE
786 *
787             NTESTT = NTESTT + NTEST
788 *
789 *           Print out tests which fail.
790 *
791             DO 150 JR = 1, NTEST
792                IFRESULT( JR ).GE.THRESH ) THEN
793 *
794 *                 If this is the first test to fail,
795 *                 print a header to the data file.
796 *
797                   IF( NERRS.EQ.0 ) THEN
798                      WRITE( NOUNIT, FMT = 9995 )'SGG'
799 *
800 *                    Matrix types
801 *
802                      WRITE( NOUNIT, FMT = 9994 )
803                      WRITE( NOUNIT, FMT = 9993 )
804                      WRITE( NOUNIT, FMT = 9992 )'Orthogonal'
805 *
806 *                    Tests performed
807 *
808                      WRITE( NOUNIT, FMT = 9991 )'orthogonal''''',
809      $                  'transpose', ( '''', J = 15 )
810 *
811                   END IF
812                   NERRS = NERRS + 1
813                   IFRESULT( JR ).LT.10000.0 ) THEN
814                      WRITE( NOUNIT, FMT = 9990 )N, JTYPE, IOLDSD, JR,
815      $                  RESULT( JR )
816                   ELSE
817                      WRITE( NOUNIT, FMT = 9989 )N, JTYPE, IOLDSD, JR,
818      $                  RESULT( JR )
819                   END IF
820                END IF
821   150       CONTINUE
822 *
823   160    CONTINUE
824   170 CONTINUE
825 *
826 *     Summary
827 *
828       CALL ALASVM( 'SGG', NOUNIT, NERRS, NTESTT, 0 )
829       RETURN
830 *
831  9999 FORMAT' SDRVGG: ', A, ' returned INFO=', I6, '.'/ 9X'N=',
832      $      I6, ', JTYPE=', I6, ', ISEED=('3( I5, ',' ), I5, ')' )
833 *
834  9998 FORMAT' SDRVGG: ', A, ' Eigenvectors from ', A, ' incorrectly ',
835      $      'normalized.'/ ' Bits of error=', 0P, G10.3','9X,
836      $      'N=', I6, ', JTYPE=', I6, ', ISEED=('3( I5, ',' ), I5,
837      $      ')' )
838 *
839  9997 FORMAT' SDRVGG: SGET53 returned INFO=', I1, ' for eigenvalue ',
840      $      I6, '.'/ 9X'N=', I6, ', JTYPE=', I6, ', ISEED=(',
841      $      3( I5, ',' ), I5, ')' )
842 *
843  9996 FORMAT' SDRVGG: S not in Schur form at eigenvalue ', I6, '.',
844      $      / 9X'N=', I6, ', JTYPE=', I6, ', ISEED=('3( I5, ',' ),
845      $      I5, ')' )
846 *
847  9995 FORMAT/ 1X, A3, ' -- Real Generalized eigenvalue problem driver'
848      $       )
849 *
850  9994 FORMAT' Matrix types (see SDRVGG for details): ' )
851 *
852  9993 FORMAT' Special Matrices:'23X,
853      $      '(J''=transposed Jordan block)',
854      $      / '   1=(0,0)  2=(I,0)  3=(0,I)  4=(I,I)  5=(J'',J'')  ',
855      $      '6=(diag(J'',I), diag(I,J''))'/ ' Diagonal Matrices:  ( ',
856      $      'D=diag(0,1,2,...) )'/ '   7=(D,I)   9=(large*D, small*I',
857      $      ')  11=(large*I, small*D)  13=(large*D, large*I)'/
858      $      '   8=(I,D)  10=(small*D, large*I)  12=(small*I, large*D) ',
859      $      ' 14=(small*D, small*I)'/ '  15=(D, reversed D)' )
860  9992 FORMAT' Matrices Rotated by Random ', A, ' Matrices U, V:',
861      $      / '  16=Transposed Jordan Blocks             19=geometric ',
862      $      'alpha, beta=0,1'/ '  17=arithm. alpha&beta             ',
863      $      '      20=arithmetic alpha, beta=0,1'/ '  18=clustered ',
864      $      'alpha, beta=0,1            21=random alpha, beta=0,1',
865      $      / ' Large & Small Matrices:'/ '  22=(large, small)   ',
866      $      '23=(small,large)    24=(small,small)    25=(large,large)',
867      $      / '  26=random O(1) matrices.' )
868 *
869  9991 FORMAT/ ' Tests performed:  (S is Schur, T is triangular, ',
870      $      'Q and Z are ', A, ','/ 20X,
871      $      'l and r are the appropriate left and right'/ 19X,
872      $      'eigenvectors, resp., a is alpha, b is beta, and'/ 19X, A,
873      $      ' means ', A, '.)'/ ' 1 = | A - Q S Z', A,
874      $      ' | / ( |A| n ulp )      2 = | B - Q T Z', A,
875      $      ' | / ( |B| n ulp )'/ ' 3 = | I - QQ', A,
876      $      ' | / ( n ulp )             4 = | I - ZZ', A,
877      $      ' | / ( n ulp )'/
878      $      ' 5 = difference between (alpha,beta) and diagonals of',
879      $      ' (S,T)'/ ' 6 = max | ( b A - a B )', A,
880      $      ' l | / const.   7 = max | ( b A - a B ) r | / const.',
881      $      / 1X )
882  9990 FORMAT' Matrix order=', I5, ', type=', I2, ', seed=',
883      $      4( I4, ',' ), ' result ', I3, ' is', 0P, F8.2 )
884  9989 FORMAT' Matrix order=', I5, ', type=', I2, ', seed=',
885      $      4( I4, ',' ), ' result ', I3, ' is', 1P, E10.3 )
886 *
887 *     End of SDRVGG
888 *
889       END