LAPACK: TESTING/LIN/zdrvgb.f Source File

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00001       SUBROUTINE ZDRVGB( DOTYPE, NN, NVAL, NRHS, THRESH, TSTERR, A, LA,
00002      $                   AFB, LAFB, ASAV, B, BSAV, X, XACT, S, WORK,
00003      $                   RWORK, IWORK, NOUT )
00004 *
00005 *  -- LAPACK test routine (version 3.1) --
00006 *     Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
00007 *     November 2006
00008 *
00009 *     .. Scalar Arguments ..
00010       LOGICAL            TSTERR
00011       INTEGER            LA, LAFB, NN, NOUT, NRHS
00012       DOUBLE PRECISION   THRESH
00013 *     ..
00014 *     .. Array Arguments ..
00015       LOGICAL            DOTYPE( * )
00016       INTEGER            IWORK( * ), NVAL( * )
00017       DOUBLE PRECISION   RWORK( * ), S( * )
00018       COMPLEX*16         A( * ), AFB( * ), ASAV( * ), B( * ), BSAV( * ),
00019      $                   WORK( * ), X( * ), XACT( * )
00020 *     ..
00021 *
00022 *  Purpose
00023 *  =======
00024 *
00025 *  ZDRVGB tests the driver routines ZGBSV and -SVX.
00026 *
00027 *  Arguments
00028 *  =========
00029 *
00030 *  DOTYPE  (input) LOGICAL array, dimension (NTYPES)
00031 *          The matrix types to be used for testing.  Matrices of type j
00032 *          (for 1 <= j <= NTYPES) are used for testing if DOTYPE(j) =
00033 *          .TRUE.; if DOTYPE(j) = .FALSE., then type j is not used.
00034 *
00035 *  NN      (input) INTEGER
00036 *          The number of values of N contained in the vector NVAL.
00037 *
00038 *  NVAL    (input) INTEGER array, dimension (NN)
00039 *          The values of the matrix column dimension N.
00040 *
00041 *  NRHS    (input) INTEGER
00042 *          The number of right hand side vectors to be generated for
00043 *          each linear system.
00044 *
00045 *  THRESH  (input) DOUBLE PRECISION
00046 *          The threshold value for the test ratios.  A result is
00047 *          included in the output file if RESULT >= THRESH.  To have
00048 *          every test ratio printed, use THRESH = 0.
00049 *
00050 *  TSTERR  (input) LOGICAL
00051 *          Flag that indicates whether error exits are to be tested.
00052 *
00053 *  A       (workspace) COMPLEX*16 array, dimension (LA)
00054 *
00055 *  LA      (input) INTEGER
00056 *          The length of the array A.  LA >= (2*NMAX-1)*NMAX
00057 *          where NMAX is the largest entry in NVAL.
00058 *
00059 *  AFB     (workspace) COMPLEX*16 array, dimension (LAFB)
00060 *
00061 *  LAFB    (input) INTEGER
00062 *          The length of the array AFB.  LAFB >= (3*NMAX-2)*NMAX
00063 *          where NMAX is the largest entry in NVAL.
00064 *
00065 *  ASAV    (workspace) COMPLEX*16 array, dimension (LA)
00066 *
00067 *  B       (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
00068 *
00069 *  BSAV    (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
00070 *
00071 *  X       (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
00072 *
00073 *  XACT    (workspace) COMPLEX*16 array, dimension (NMAX*NRHS)
00074 *
00075 *  S       (workspace) DOUBLE PRECISION array, dimension (2*NMAX)
00076 *
00077 *  WORK    (workspace) COMPLEX*16 array, dimension
00078 *                      (NMAX*max(3,NRHS,NMAX))
00079 *
00080 *  RWORK   (workspace) DOUBLE PRECISION array, dimension
00081 *                      (max(NMAX,2*NRHS))
00082 *
00083 *  IWORK   (workspace) INTEGER array, dimension (NMAX)
00084 *
00085 *  NOUT    (input) INTEGER
00086 *          The unit number for output.
00087 *
00088 *  =====================================================================
00089 *
00090 *     .. Parameters ..
00091       DOUBLE PRECISION   ONE, ZERO
00092       PARAMETER          ( ONE = 1.0D+0, ZERO = 0.0D+0 )
00093       INTEGER            NTYPES
00094       PARAMETER          ( NTYPES = 8 )
00095       INTEGER            NTESTS
00096       PARAMETER          ( NTESTS = 7 )
00097       INTEGER            NTRAN
00098       PARAMETER          ( NTRAN = 3 )
00099 *     ..
00100 *     .. Local Scalars ..
00101       LOGICAL            EQUIL, NOFACT, PREFAC, TRFCON, ZEROT
00102       CHARACTER          DIST, EQUED, FACT, TRANS, TYPE, XTYPE
00103       CHARACTER*3        PATH
00104       INTEGER            I, I1, I2, IEQUED, IFACT, IKL, IKU, IMAT, IN,
00105      $                   INFO, IOFF, ITRAN, IZERO, J, K, K1, KL, KU,
00106      $                   LDA, LDAFB, LDB, MODE, N, NB, NBMIN, NERRS,
00107      $                   NFACT, NFAIL, NIMAT, NKL, NKU, NRUN, NT
00108       DOUBLE PRECISION   AINVNM, AMAX, ANORM, ANORMI, ANORMO, ANRMPV,
00109      $                   CNDNUM, COLCND, RCOND, RCONDC, RCONDI, RCONDO,
00110      $                   ROLDC, ROLDI, ROLDO, ROWCND, RPVGRW
00111 *     ..
00112 *     .. Local Arrays ..
00113       CHARACTER          EQUEDS( 4 ), FACTS( 3 ), TRANSS( NTRAN )
00114       INTEGER            ISEED( 4 ), ISEEDY( 4 )
00115       DOUBLE PRECISION   RDUM( 1 ), RESULT( NTESTS )
00116 *     ..
00117 *     .. External Functions ..
00118       LOGICAL            LSAME
00119       DOUBLE PRECISION   DGET06, DLAMCH, ZLANGB, ZLANGE, ZLANTB
00120       EXTERNAL           LSAME, DGET06, DLAMCH, ZLANGB, ZLANGE, ZLANTB
00121 *     ..
00122 *     .. External Subroutines ..
00123       EXTERNAL           ALADHD, ALAERH, ALASVM, XLAENV, ZERRVX, ZGBEQU,
00124      $                   ZGBSV, ZGBSVX, ZGBT01, ZGBT02, ZGBT05, ZGBTRF,
00125      $                   ZGBTRS, ZGET04, ZLACPY, ZLAQGB, ZLARHS, ZLASET,
00126      $                   ZLATB4, ZLATMS
00127 *     ..
00128 *     .. Intrinsic Functions ..
00129       INTRINSIC          ABS, DCMPLX, MAX, MIN
00130 *     ..
00131 *     .. Scalars in Common ..
00132       LOGICAL            LERR, OK
00133       CHARACTER*32       SRNAMT
00134       INTEGER            INFOT, NUNIT
00135 *     ..
00136 *     .. Common blocks ..
00137       COMMON             / INFOC / INFOT, NUNIT, OK, LERR
00138       COMMON             / SRNAMC / SRNAMT
00139 *     ..
00140 *     .. Data statements ..
00141       DATA               ISEEDY / 1988, 1989, 1990, 1991 /
00142       DATA               TRANSS / 'N', 'T', 'C' /
00143       DATA               FACTS / 'F', 'N', 'E' /
00144       DATA               EQUEDS / 'N', 'R', 'C', 'B' /
00145 *     ..
00146 *     .. Executable Statements ..
00147 *
00148 *     Initialize constants and the random number seed.
00149 *
00150       PATH( 1: 1 ) = 'Zomplex precision'
00151       PATH( 2: 3 ) = 'GB'
00152       NRUN = 0
00153       NFAIL = 0
00154       NERRS = 0
00155       DO 10 I = 1, 4
00156          ISEED( I ) = ISEEDY( I )
00157    10 CONTINUE
00158 *
00159 *     Test the error exits
00160 *
00161       IF( TSTERR )
00162      $   CALL ZERRVX( PATH, NOUT )
00163       INFOT = 0
00164 *
00165 *     Set the block size and minimum block size for testing.
00166 *
00167       NB = 1
00168       NBMIN = 2
00169       CALL XLAENV( 1, NB )
00170       CALL XLAENV( 2, NBMIN )
00171 *
00172 *     Do for each value of N in NVAL
00173 *
00174       DO 150 IN = 1, NN
00175          N = NVAL( IN )
00176          LDB = MAX( N, 1 )
00177          XTYPE = 'N'
00178 *
00179 *        Set limits on the number of loop iterations.
00180 *
00181          NKL = MAX( 1, MIN( N, 4 ) )
00182          IF( N.EQ.0 )
00183      $      NKL = 1
00184          NKU = NKL
00185          NIMAT = NTYPES
00186          IF( N.LE.0 )
00187      $      NIMAT = 1
00188 *
00189          DO 140 IKL = 1, NKL
00190 *
00191 *           Do for KL = 0, N-1, (3N-1)/4, and (N+1)/4. This order makes
00192 *           it easier to skip redundant values for small values of N.
00193 *
00194             IF( IKL.EQ.1 ) THEN
00195                KL = 0
00196             ELSE IF( IKL.EQ.2 ) THEN
00197                KL = MAX( N-1, 0 )
00198             ELSE IF( IKL.EQ.3 ) THEN
00199                KL = ( 3*N-1 ) / 4
00200             ELSE IF( IKL.EQ.4 ) THEN
00201                KL = ( N+1 ) / 4
00202             END IF
00203             DO 130 IKU = 1, NKU
00204 *
00205 *              Do for KU = 0, N-1, (3N-1)/4, and (N+1)/4. This order
00206 *              makes it easier to skip redundant values for small
00207 *              values of N.
00208 *
00209                IF( IKU.EQ.1 ) THEN
00210                   KU = 0
00211                ELSE IF( IKU.EQ.2 ) THEN
00212                   KU = MAX( N-1, 0 )
00213                ELSE IF( IKU.EQ.3 ) THEN
00214                   KU = ( 3*N-1 ) / 4
00215                ELSE IF( IKU.EQ.4 ) THEN
00216                   KU = ( N+1 ) / 4
00217                END IF
00218 *
00219 *              Check that A and AFB are big enough to generate this
00220 *              matrix.
00221 *
00222                LDA = KL + KU + 1
00223                LDAFB = 2*KL + KU + 1
00224                IF( LDA*N.GT.LA .OR. LDAFB*N.GT.LAFB ) THEN
00225                   IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00226      $               CALL ALADHD( NOUT, PATH )
00227                   IF( LDA*N.GT.LA ) THEN
00228                      WRITE( NOUT, FMT = 9999 )LA, N, KL, KU,
00229      $                  N*( KL+KU+1 )
00230                      NERRS = NERRS + 1
00231                   END IF
00232                   IF( LDAFB*N.GT.LAFB ) THEN
00233                      WRITE( NOUT, FMT = 9998 )LAFB, N, KL, KU,
00234      $                  N*( 2*KL+KU+1 )
00235                      NERRS = NERRS + 1
00236                   END IF
00237                   GO TO 130
00238                END IF
00239 *
00240                DO 120 IMAT = 1, NIMAT
00241 *
00242 *                 Do the tests only if DOTYPE( IMAT ) is true.
00243 *
00244                   IF( .NOT.DOTYPE( IMAT ) )
00245      $               GO TO 120
00246 *
00247 *                 Skip types 2, 3, or 4 if the matrix is too small.
00248 *
00249                   ZEROT = IMAT.GE.2 .AND. IMAT.LE.4
00250                   IF( ZEROT .AND. N.LT.IMAT-1 )
00251      $               GO TO 120
00252 *
00253 *                 Set up parameters with ZLATB4 and generate a
00254 *                 test matrix with ZLATMS.
00255 *
00256                   CALL ZLATB4( PATH, IMAT, N, N, TYPE, KL, KU, ANORM,
00257      $                         MODE, CNDNUM, DIST )
00258                   RCONDC = ONE / CNDNUM
00259 *
00260                   SRNAMT = 'ZLATMS'
00261                   CALL ZLATMS( N, N, DIST, ISEED, TYPE, RWORK, MODE,
00262      $                         CNDNUM, ANORM, KL, KU, 'Z', A, LDA, WORK,
00263      $                         INFO )
00264 *
00265 *                 Check the error code from ZLATMS.
00266 *
00267                   IF( INFO.NE.0 ) THEN
00268                      CALL ALAERH( PATH, 'ZLATMS', INFO, 0, ' ', N, N,
00269      $                            KL, KU, -1, IMAT, NFAIL, NERRS, NOUT )
00270                      GO TO 120
00271                   END IF
00272 *
00273 *                 For types 2, 3, and 4, zero one or more columns of
00274 *                 the matrix to test that INFO is returned correctly.
00275 *
00276                   IZERO = 0
00277                   IF( ZEROT ) THEN
00278                      IF( IMAT.EQ.2 ) THEN
00279                         IZERO = 1
00280                      ELSE IF( IMAT.EQ.3 ) THEN
00281                         IZERO = N
00282                      ELSE
00283                         IZERO = N / 2 + 1
00284                      END IF
00285                      IOFF = ( IZERO-1 )*LDA
00286                      IF( IMAT.LT.4 ) THEN
00287                         I1 = MAX( 1, KU+2-IZERO )
00288                         I2 = MIN( KL+KU+1, KU+1+( N-IZERO ) )
00289                         DO 20 I = I1, I2
00290                            A( IOFF+I ) = ZERO
00291    20                   CONTINUE
00292                      ELSE
00293                         DO 40 J = IZERO, N
00294                            DO 30 I = MAX( 1, KU+2-J ),
00295      $                             MIN( KL+KU+1, KU+1+( N-J ) )
00296                               A( IOFF+I ) = ZERO
00297    30                      CONTINUE
00298                            IOFF = IOFF + LDA
00299    40                   CONTINUE
00300                      END IF
00301                   END IF
00302 *
00303 *                 Save a copy of the matrix A in ASAV.
00304 *
00305                   CALL ZLACPY( 'Full', KL+KU+1, N, A, LDA, ASAV, LDA )
00306 *
00307                   DO 110 IEQUED = 1, 4
00308                      EQUED = EQUEDS( IEQUED )
00309                      IF( IEQUED.EQ.1 ) THEN
00310                         NFACT = 3
00311                      ELSE
00312                         NFACT = 1
00313                      END IF
00314 *
00315                      DO 100 IFACT = 1, NFACT
00316                         FACT = FACTS( IFACT )
00317                         PREFAC = LSAME( FACT, 'F' )
00318                         NOFACT = LSAME( FACT, 'N' )
00319                         EQUIL = LSAME( FACT, 'E' )
00320 *
00321                         IF( ZEROT ) THEN
00322                            IF( PREFAC )
00323      $                        GO TO 100
00324                            RCONDO = ZERO
00325                            RCONDI = ZERO
00326 *
00327                         ELSE IF( .NOT.NOFACT ) THEN
00328 *
00329 *                          Compute the condition number for comparison
00330 *                          with the value returned by DGESVX (FACT =
00331 *                          'N' reuses the condition number from the
00332 *                          previous iteration with FACT = 'F').
00333 *
00334                            CALL ZLACPY( 'Full', KL+KU+1, N, ASAV, LDA,
00335      $                                  AFB( KL+1 ), LDAFB )
00336                            IF( EQUIL .OR. IEQUED.GT.1 ) THEN
00337 *
00338 *                             Compute row and column scale factors to
00339 *                             equilibrate the matrix A.
00340 *
00341                               CALL ZGBEQU( N, N, KL, KU, AFB( KL+1 ),
00342      $                                     LDAFB, S, S( N+1 ), ROWCND,
00343      $                                     COLCND, AMAX, INFO )
00344                               IF( INFO.EQ.0 .AND. N.GT.0 ) THEN
00345                                  IF( LSAME( EQUED, 'R' ) ) THEN
00346                                     ROWCND = ZERO
00347                                     COLCND = ONE
00348                                  ELSE IF( LSAME( EQUED, 'C' ) ) THEN
00349                                     ROWCND = ONE
00350                                     COLCND = ZERO
00351                                  ELSE IF( LSAME( EQUED, 'B' ) ) THEN
00352                                     ROWCND = ZERO
00353                                     COLCND = ZERO
00354                                  END IF
00355 *
00356 *                                Equilibrate the matrix.
00357 *
00358                                  CALL ZLAQGB( N, N, KL, KU, AFB( KL+1 ),
00359      $                                        LDAFB, S, S( N+1 ),
00360      $                                        ROWCND, COLCND, AMAX,
00361      $                                        EQUED )
00362                               END IF
00363                            END IF
00364 *
00365 *                          Save the condition number of the
00366 *                          non-equilibrated system for use in ZGET04.
00367 *
00368                            IF( EQUIL ) THEN
00369                               ROLDO = RCONDO
00370                               ROLDI = RCONDI
00371                            END IF
00372 *
00373 *                          Compute the 1-norm and infinity-norm of A.
00374 *
00375                            ANORMO = ZLANGB( '1', N, KL, KU, AFB( KL+1 ),
00376      $                              LDAFB, RWORK )
00377                            ANORMI = ZLANGB( 'I', N, KL, KU, AFB( KL+1 ),
00378      $                              LDAFB, RWORK )
00379 *
00380 *                          Factor the matrix A.
00381 *
00382                            CALL ZGBTRF( N, N, KL, KU, AFB, LDAFB, IWORK,
00383      $                                  INFO )
00384 *
00385 *                          Form the inverse of A.
00386 *
00387                            CALL ZLASET( 'Full', N, N, DCMPLX( ZERO ),
00388      $                                  DCMPLX( ONE ), WORK, LDB )
00389                            SRNAMT = 'ZGBTRS'
00390                            CALL ZGBTRS( 'No transpose', N, KL, KU, N,
00391      $                                  AFB, LDAFB, IWORK, WORK, LDB,
00392      $                                  INFO )
00393 *
00394 *                          Compute the 1-norm condition number of A.
00395 *
00396                            AINVNM = ZLANGE( '1', N, N, WORK, LDB,
00397      $                              RWORK )
00398                            IF( ANORMO.LE.ZERO .OR. AINVNM.LE.ZERO ) THEN
00399                               RCONDO = ONE
00400                            ELSE
00401                               RCONDO = ( ONE / ANORMO ) / AINVNM
00402                            END IF
00403 *
00404 *                          Compute the infinity-norm condition number
00405 *                          of A.
00406 *
00407                            AINVNM = ZLANGE( 'I', N, N, WORK, LDB,
00408      $                              RWORK )
00409                            IF( ANORMI.LE.ZERO .OR. AINVNM.LE.ZERO ) THEN
00410                               RCONDI = ONE
00411                            ELSE
00412                               RCONDI = ( ONE / ANORMI ) / AINVNM
00413                            END IF
00414                         END IF
00415 *
00416                         DO 90 ITRAN = 1, NTRAN
00417 *
00418 *                          Do for each value of TRANS.
00419 *
00420                            TRANS = TRANSS( ITRAN )
00421                            IF( ITRAN.EQ.1 ) THEN
00422                               RCONDC = RCONDO
00423                            ELSE
00424                               RCONDC = RCONDI
00425                            END IF
00426 *
00427 *                          Restore the matrix A.
00428 *
00429                            CALL ZLACPY( 'Full', KL+KU+1, N, ASAV, LDA,
00430      $                                  A, LDA )
00431 *
00432 *                          Form an exact solution and set the right hand
00433 *                          side.
00434 *
00435                            SRNAMT = 'ZLARHS'
00436                            CALL ZLARHS( PATH, XTYPE, 'Full', TRANS, N,
00437      $                                  N, KL, KU, NRHS, A, LDA, XACT,
00438      $                                  LDB, B, LDB, ISEED, INFO )
00439                            XTYPE = 'C'
00440                            CALL ZLACPY( 'Full', N, NRHS, B, LDB, BSAV,
00441      $                                  LDB )
00442 *
00443                            IF( NOFACT .AND. ITRAN.EQ.1 ) THEN
00444 *
00445 *                             --- Test ZGBSV  ---
00446 *
00447 *                             Compute the LU factorization of the matrix
00448 *                             and solve the system.
00449 *
00450                               CALL ZLACPY( 'Full', KL+KU+1, N, A, LDA,
00451      $                                     AFB( KL+1 ), LDAFB )
00452                               CALL ZLACPY( 'Full', N, NRHS, B, LDB, X,
00453      $                                     LDB )
00454 *
00455                               SRNAMT = 'ZGBSV '
00456                               CALL ZGBSV( N, KL, KU, NRHS, AFB, LDAFB,
00457      $                                    IWORK, X, LDB, INFO )
00458 *
00459 *                             Check error code from ZGBSV .
00460 *
00461                               IF( INFO.NE.IZERO )
00462      $                           CALL ALAERH( PATH, 'ZGBSV ', INFO,
00463      $                                        IZERO, ' ', N, N, KL, KU,
00464      $                                        NRHS, IMAT, NFAIL, NERRS,
00465      $                                        NOUT )
00466 *
00467 *                             Reconstruct matrix from factors and
00468 *                             compute residual.
00469 *
00470                               CALL ZGBT01( N, N, KL, KU, A, LDA, AFB,
00471      $                                     LDAFB, IWORK, WORK,
00472      $                                     RESULT( 1 ) )
00473                               NT = 1
00474                               IF( IZERO.EQ.0 ) THEN
00475 *
00476 *                                Compute residual of the computed
00477 *                                solution.
00478 *
00479                                  CALL ZLACPY( 'Full', N, NRHS, B, LDB,
00480      $                                        WORK, LDB )
00481                                  CALL ZGBT02( 'No transpose', N, N, KL,
00482      $                                        KU, NRHS, A, LDA, X, LDB,
00483      $                                        WORK, LDB, RESULT( 2 ) )
00484 *
00485 *                                Check solution from generated exact
00486 *                                solution.
00487 *
00488                                  CALL ZGET04( N, NRHS, X, LDB, XACT,
00489      $                                        LDB, RCONDC, RESULT( 3 ) )
00490                                  NT = 3
00491                               END IF
00492 *
00493 *                             Print information about the tests that did
00494 *                             not pass the threshold.
00495 *
00496                               DO 50 K = 1, NT
00497                                  IF( RESULT( K ).GE.THRESH ) THEN
00498                                     IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00499      $                                 CALL ALADHD( NOUT, PATH )
00500                                     WRITE( NOUT, FMT = 9997 )'ZGBSV ',
00501      $                                 N, KL, KU, IMAT, K, RESULT( K )
00502                                     NFAIL = NFAIL + 1
00503                                  END IF
00504    50                         CONTINUE
00505                               NRUN = NRUN + NT
00506                            END IF
00507 *
00508 *                          --- Test ZGBSVX ---
00509 *
00510                            IF( .NOT.PREFAC )
00511      $                        CALL ZLASET( 'Full', 2*KL+KU+1, N,
00512      $                                     DCMPLX( ZERO ),
00513      $                                     DCMPLX( ZERO ), AFB, LDAFB )
00514                            CALL ZLASET( 'Full', N, NRHS, DCMPLX( ZERO ),
00515      $                                  DCMPLX( ZERO ), X, LDB )
00516                            IF( IEQUED.GT.1 .AND. N.GT.0 ) THEN
00517 *
00518 *                             Equilibrate the matrix if FACT = 'F' and
00519 *                             EQUED = 'R', 'C', or 'B'.
00520 *
00521                               CALL ZLAQGB( N, N, KL, KU, A, LDA, S,
00522      $                                     S( N+1 ), ROWCND, COLCND,
00523      $                                     AMAX, EQUED )
00524                            END IF
00525 *
00526 *                          Solve the system and compute the condition
00527 *                          number and error bounds using ZGBSVX.
00528 *
00529                            SRNAMT = 'ZGBSVX'
00530                            CALL ZGBSVX( FACT, TRANS, N, KL, KU, NRHS, A,
00531      $                                  LDA, AFB, LDAFB, IWORK, EQUED,
00532      $                                  S, S( LDB+1 ), B, LDB, X, LDB,
00533      $                                  RCOND, RWORK, RWORK( NRHS+1 ),
00534      $                                  WORK, RWORK( 2*NRHS+1 ), INFO )
00535 *
00536 *                          Check the error code from ZGBSVX.
00537 *
00538                            IF( INFO.NE.IZERO )
00539      $                        CALL ALAERH( PATH, 'ZGBSVX', INFO, IZERO,
00540      $                                     FACT // TRANS, N, N, KL, KU,
00541      $                                     NRHS, IMAT, NFAIL, NERRS,
00542      $                                     NOUT )
00543 *                          Compare RWORK(2*NRHS+1) from ZGBSVX with the
00544 *                          computed reciprocal pivot growth RPVGRW
00545 *
00546                            IF( INFO.NE.0 ) THEN
00547                               ANRMPV = ZERO
00548                               DO 70 J = 1, INFO
00549                                  DO 60 I = MAX( KU+2-J, 1 ),
00550      $                                   MIN( N+KU+1-J, KL+KU+1 )
00551                                     ANRMPV = MAX( ANRMPV,
00552      $                                       ABS( A( I+( J-1 )*LDA ) ) )
00553    60                            CONTINUE
00554    70                         CONTINUE
00555                               RPVGRW = ZLANTB( 'M', 'U', 'N', INFO,
00556      $                                 MIN( INFO-1, KL+KU ),
00557      $                                 AFB( MAX( 1, KL+KU+2-INFO ) ),
00558      $                                 LDAFB, RDUM )
00559                               IF( RPVGRW.EQ.ZERO ) THEN
00560                                  RPVGRW = ONE
00561                               ELSE
00562                                  RPVGRW = ANRMPV / RPVGRW
00563                               END IF
00564                            ELSE
00565                               RPVGRW = ZLANTB( 'M', 'U', 'N', N, KL+KU,
00566      $                                 AFB, LDAFB, RDUM )
00567                               IF( RPVGRW.EQ.ZERO ) THEN
00568                                  RPVGRW = ONE
00569                               ELSE
00570                                  RPVGRW = ZLANGB( 'M', N, KL, KU, A,
00571      $                                    LDA, RDUM ) / RPVGRW
00572                               END IF
00573                            END IF
00574                            RESULT( 7 ) = ABS( RPVGRW-RWORK( 2*NRHS+1 ) )
00575      $                                    / MAX( RWORK( 2*NRHS+1 ),
00576      $                                   RPVGRW ) / DLAMCH( 'E' )
00577 *
00578                            IF( .NOT.PREFAC ) THEN
00579 *
00580 *                             Reconstruct matrix from factors and
00581 *                             compute residual.
00582 *
00583                               CALL ZGBT01( N, N, KL, KU, A, LDA, AFB,
00584      $                                     LDAFB, IWORK, WORK,
00585      $                                     RESULT( 1 ) )
00586                               K1 = 1
00587                            ELSE
00588                               K1 = 2
00589                            END IF
00590 *
00591                            IF( INFO.EQ.0 ) THEN
00592                               TRFCON = .FALSE.
00593 *
00594 *                             Compute residual of the computed solution.
00595 *
00596                               CALL ZLACPY( 'Full', N, NRHS, BSAV, LDB,
00597      $                                     WORK, LDB )
00598                               CALL ZGBT02( TRANS, N, N, KL, KU, NRHS,
00599      $                                     ASAV, LDA, X, LDB, WORK, LDB,
00600      $                                     RESULT( 2 ) )
00601 *
00602 *                             Check solution from generated exact
00603 *                             solution.
00604 *
00605                               IF( NOFACT .OR. ( PREFAC .AND.
00606      $                            LSAME( EQUED, 'N' ) ) ) THEN
00607                                  CALL ZGET04( N, NRHS, X, LDB, XACT,
00608      $                                        LDB, RCONDC, RESULT( 3 ) )
00609                               ELSE
00610                                  IF( ITRAN.EQ.1 ) THEN
00611                                     ROLDC = ROLDO
00612                                  ELSE
00613                                     ROLDC = ROLDI
00614                                  END IF
00615                                  CALL ZGET04( N, NRHS, X, LDB, XACT,
00616      $                                        LDB, ROLDC, RESULT( 3 ) )
00617                               END IF
00618 *
00619 *                             Check the error bounds from iterative
00620 *                             refinement.
00621 *
00622                               CALL ZGBT05( TRANS, N, KL, KU, NRHS, ASAV,
00623      $                                     LDA, BSAV, LDB, X, LDB, XACT,
00624      $                                     LDB, RWORK, RWORK( NRHS+1 ),
00625      $                                     RESULT( 4 ) )
00626                            ELSE
00627                               TRFCON = .TRUE.
00628                            END IF
00629 *
00630 *                          Compare RCOND from ZGBSVX with the computed
00631 *                          value in RCONDC.
00632 *
00633                            RESULT( 6 ) = DGET06( RCOND, RCONDC )
00634 *
00635 *                          Print information about the tests that did
00636 *                          not pass the threshold.
00637 *
00638                            IF( .NOT.TRFCON ) THEN
00639                               DO 80 K = K1, NTESTS
00640                                  IF( RESULT( K ).GE.THRESH ) THEN
00641                                     IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00642      $                                 CALL ALADHD( NOUT, PATH )
00643                                     IF( PREFAC ) THEN
00644                                        WRITE( NOUT, FMT = 9995 )
00645      $                                    'ZGBSVX', FACT, TRANS, N, KL,
00646      $                                    KU, EQUED, IMAT, K,
00647      $                                    RESULT( K )
00648                                     ELSE
00649                                        WRITE( NOUT, FMT = 9996 )
00650      $                                    'ZGBSVX', FACT, TRANS, N, KL,
00651      $                                    KU, IMAT, K, RESULT( K )
00652                                     END IF
00653                                     NFAIL = NFAIL + 1
00654                                  END IF
00655    80                         CONTINUE
00656                               NRUN = NRUN + 7 - K1
00657                            ELSE
00658                               IF( RESULT( 1 ).GE.THRESH .AND. .NOT.
00659      $                            PREFAC ) THEN
00660                                  IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00661      $                              CALL ALADHD( NOUT, PATH )
00662                                  IF( PREFAC ) THEN
00663                                     WRITE( NOUT, FMT = 9995 )'ZGBSVX',
00664      $                                 FACT, TRANS, N, KL, KU, EQUED,
00665      $                                 IMAT, 1, RESULT( 1 )
00666                                  ELSE
00667                                     WRITE( NOUT, FMT = 9996 )'ZGBSVX',
00668      $                                 FACT, TRANS, N, KL, KU, IMAT, 1,
00669      $                                 RESULT( 1 )
00670                                  END IF
00671                                  NFAIL = NFAIL + 1
00672                                  NRUN = NRUN + 1
00673                               END IF
00674                               IF( RESULT( 6 ).GE.THRESH ) THEN
00675                                  IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00676      $                              CALL ALADHD( NOUT, PATH )
00677                                  IF( PREFAC ) THEN
00678                                     WRITE( NOUT, FMT = 9995 )'ZGBSVX',
00679      $                                 FACT, TRANS, N, KL, KU, EQUED,
00680      $                                 IMAT, 6, RESULT( 6 )
00681                                  ELSE
00682                                     WRITE( NOUT, FMT = 9996 )'ZGBSVX',
00683      $                                 FACT, TRANS, N, KL, KU, IMAT, 6,
00684      $                                 RESULT( 6 )
00685                                  END IF
00686                                  NFAIL = NFAIL + 1
00687                                  NRUN = NRUN + 1
00688                               END IF
00689                               IF( RESULT( 7 ).GE.THRESH ) THEN
00690                                  IF( NFAIL.EQ.0 .AND. NERRS.EQ.0 )
00691      $                              CALL ALADHD( NOUT, PATH )
00692                                  IF( PREFAC ) THEN
00693                                     WRITE( NOUT, FMT = 9995 )'ZGBSVX',
00694      $                                 FACT, TRANS, N, KL, KU, EQUED,
00695      $                                 IMAT, 7, RESULT( 7 )
00696                                  ELSE
00697                                     WRITE( NOUT, FMT = 9996 )'ZGBSVX',
00698      $                                 FACT, TRANS, N, KL, KU, IMAT, 7,
00699      $                                 RESULT( 7 )
00700                                  END IF
00701                                  NFAIL = NFAIL + 1
00702                                  NRUN = NRUN + 1
00703                               END IF
00704                            END IF
00705    90                   CONTINUE
00706   100                CONTINUE
00707   110             CONTINUE
00708   120          CONTINUE
00709   130       CONTINUE
00710   140    CONTINUE
00711   150 CONTINUE
00712 *
00713 *     Print a summary of the results.
00714 *
00715       CALL ALASVM( PATH, NOUT, NFAIL, NRUN, NERRS )
00716 *
00717  9999 FORMAT( ' *** In ZDRVGB, LA=', I5, ' is too small for N=', I5,
00718      $      ', KU=', I5, ', KL=', I5, / ' ==> Increase LA to at least ',
00719      $      I5 )
00720  9998 FORMAT( ' *** In ZDRVGB, LAFB=', I5, ' is too small for N=', I5,
00721      $      ', KU=', I5, ', KL=', I5, /
00722      $      ' ==> Increase LAFB to at least ', I5 )
00723  9997 FORMAT( 1X, A, ', N=', I5, ', KL=', I5, ', KU=', I5, ', type ',
00724      $      I1, ', test(', I1, ')=', G12.5 )
00725  9996 FORMAT( 1X, A, '( ''', A1, ''',''', A1, ''',', I5, ',', I5, ',',
00726      $      I5, ',...), type ', I1, ', test(', I1, ')=', G12.5 )
00727  9995 FORMAT( 1X, A, '( ''', A1, ''',''', A1, ''',', I5, ',', I5, ',',
00728      $      I5, ',...), EQUED=''', A1, ''', type ', I1, ', test(', I1,
00729      $      ')=', G12.5 )
00730 *
00731       RETURN
00732 *
00733 *     End of ZDRVGB
00734 *
00735       END