cckgsv.f

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*> \brief \b CCKGSV
*
*  =========== DOCUMENTATION ===========
*
* Online html documentation available at
*            http://www.netlib.org/lapack/explore-html/
*
*  Definition:
*  ===========
*
*       SUBROUTINE CCKGSV( NM, MVAL, PVAL, NVAL, NMATS, ISEED, THRESH,
*                          NMAX, A, AF, B, BF, U, V, Q, ALPHA, BETA, R,
*                          IWORK, WORK, RWORK, NIN, NOUT, INFO )
*
*       .. Scalar Arguments ..
*       INTEGER            INFO, NIN, NM, NMATS, NMAX, NOUT
*       REAL               THRESH
*       ..
*       .. Array Arguments ..
*       INTEGER            ISEED( 4 ), IWORK( * ), MVAL( * ), NVAL( * ),
*      $                   PVAL( * )
*       REAL               ALPHA( * ), BETA( * ), RWORK( * )
*       COMPLEX            A( * ), AF( * ), B( * ), BF( * ), Q( * ),
*      $                   R( * ), U( * ), V( * ), WORK( * )
*       ..
*
*
*> \par Purpose:
*  =============
*>
*> \verbatim
*>
*> CCKGSV tests CGGSVD:
*>        the GSVD for M-by-N matrix A and P-by-N matrix B.
*> \endverbatim
*
*  Arguments:
*  ==========
*
*> \param[in] NM
*> \verbatim
*>          NM is INTEGER
*>          The number of values of M contained in the vector MVAL.
*> \endverbatim
*>
*> \param[in] MVAL
*> \verbatim
*>          MVAL is INTEGER array, dimension (NM)
*>          The values of the matrix row dimension M.
*> \endverbatim
*>
*> \param[in] PVAL
*> \verbatim
*>          PVAL is INTEGER array, dimension (NP)
*>          The values of the matrix row dimension P.
*> \endverbatim
*>
*> \param[in] NVAL
*> \verbatim
*>          NVAL is INTEGER array, dimension (NN)
*>          The values of the matrix column dimension N.
*> \endverbatim
*>
*> \param[in] NMATS
*> \verbatim
*>          NMATS is INTEGER
*>          The number of matrix types to be tested for each combination
*>          of matrix dimensions.  If NMATS >= NTYPES (the maximum
*>          number of matrix types), then all the different types are
*>          generated for testing.  If NMATS < NTYPES, another input line
*>          is read to get the numbers of the matrix types to be used.
*> \endverbatim
*>
*> \param[in,out] ISEED
*> \verbatim
*>          ISEED is INTEGER array, dimension (4)
*>          On entry, the seed of the random number generator.  The array
*>          elements should be between 0 and 4095, otherwise they will be
*>          reduced mod 4096, and ISEED(4) must be odd.
*>          On exit, the next seed in the random number sequence after
*>          all the test matrices have been generated.
*> \endverbatim
*>
*> \param[in] THRESH
*> \verbatim
*>          THRESH is REAL
*>          The threshold value for the test ratios.  A result is
*>          included in the output file if RESULT >= THRESH.  To have
*>          every test ratio printed, use THRESH = 0.
*> \endverbatim
*>
*> \param[in] NMAX
*> \verbatim
*>          NMAX is INTEGER
*>          The maximum value permitted for M or N, used in dimensioning
*>          the work arrays.
*> \endverbatim
*>
*> \param[out] A
*> \verbatim
*>          A is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] AF
*> \verbatim
*>          AF is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] B
*> \verbatim
*>          B is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] BF
*> \verbatim
*>          BF is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] U
*> \verbatim
*>          U is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] V
*> \verbatim
*>          V is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] Q
*> \verbatim
*>          Q is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] ALPHA
*> \verbatim
*>          ALPHA is REAL array, dimension (NMAX)
*> \endverbatim
*>
*> \param[out] BETA
*> \verbatim
*>          BETA is REAL array, dimension (NMAX)
*> \endverbatim
*>
*> \param[out] R
*> \verbatim
*>          R is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] IWORK
*> \verbatim
*>          IWORK is INTEGER array, dimension (NMAX)
*> \endverbatim
*>
*> \param[out] WORK
*> \verbatim
*>          WORK is COMPLEX array, dimension (NMAX*NMAX)
*> \endverbatim
*>
*> \param[out] RWORK
*> \verbatim
*>          RWORK is REAL array, dimension (NMAX)
*> \endverbatim
*>
*> \param[in] NIN
*> \verbatim
*>          NIN is INTEGER
*>          The unit number for input.
*> \endverbatim
*>
*> \param[in] NOUT
*> \verbatim
*>          NOUT is INTEGER
*>          The unit number for output.
*> \endverbatim
*>
*> \param[out] INFO
*> \verbatim
*>          INFO is INTEGER
*>          = 0 :  successful exit
*>          > 0 :  If CLATMS returns an error code, the absolute value
*>                 of it is returned.
*> \endverbatim
*
*  Authors:
*  ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \ingroup complex_eig
*
*  =====================================================================
      SUBROUTINE cckgsv( NM, MVAL, PVAL, NVAL, NMATS, ISEED, THRESH,
     $                   NMAX, A, AF, B, BF, U, V, Q, ALPHA, BETA, R,
     $                   IWORK, WORK, RWORK, NIN, NOUT, INFO )
*
*  -- LAPACK test routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. Scalar Arguments ..
      INTEGER            INFO, NIN, NM, NMATS, NMAX, NOUT
      REAL               THRESH
*     ..
*     .. Array Arguments ..
      INTEGER            ISEED( 4 ), IWORK( * ), MVAL( * ), NVAL( * ),
     $                   PVAL( * )
      REAL               ALPHA( * ), BETA( * ), RWORK( * )
      COMPLEX            A( * ), AF( * ), B( * ), BF( * ), Q( * ),
     $                   r( * ), u( * ), v( * ), work( * )
*     ..
*
*  =====================================================================
*
*     .. Parameters ..
      INTEGER            NTESTS
      PARAMETER          ( NTESTS = 12 )
      INTEGER            NTYPES
      parameter( ntypes = 8 )
*     ..
*     .. Local Scalars ..
      LOGICAL            FIRSTT
      CHARACTER          DISTA, DISTB, TYPE
      CHARACTER*3        PATH
      INTEGER            I, IINFO, IM, IMAT, KLA, KLB, KUA, KUB, LDA,
     $                   ldb, ldq, ldr, ldu, ldv, lwork, m, modea,
     $                   modeb, n, nfail, nrun, nt, p, k, l
      REAL               ANORM, BNORM, CNDNMA, CNDNMB
*     ..
*     .. Local Arrays ..
      LOGICAL            DOTYPE( NTYPES )
      REAL               RESULT( NTESTS )
*     ..
*     .. External Subroutines ..
      EXTERNAL           alahdg, alareq, alasum, clatms, slatb9, cgsvts3
*     ..
*     .. Intrinsic Functions ..
      INTRINSIC          abs
*     ..
*     .. Executable Statements ..
*
*     Initialize constants and the random number seed.
*
      path( 1: 3 ) = 'GSV'
      info = 0
      nrun = 0
      nfail = 0
      firstt = .true.
      CALL alareq( path, nmats, dotype, ntypes, nin, nout )
      lda = nmax
      ldb = nmax
      ldu = nmax
      ldv = nmax
      ldq = nmax
      ldr = nmax
      lwork = nmax*nmax
*
*     Specific cases
*
*     Test: https://github.com/Reference-LAPACK/lapack/issues/411#issue-608776973
*
      m = 6
      p = 6
      n = 6
      a(1:m*n) = cmplx(1.e0, 0.e0)
      b(1:m*n) = cmplx(0.e0, 0.e0)
      b(1+0*m) = cmplx(9.e19, 0.e0)
      b(2+1*m) = cmplx(9.e18, 0.e0)
      b(3+2*m) = cmplx(9.e17, 0.e0)
      b(4+3*m) = cmplx(9.e16, 0.e0)
      b(5+4*m) = cmplx(9.e15, 0.e0)
      b(6+5*m) = cmplx(9.e14, 0.e0)
      CALL cggsvd3('N','N','N', m, p, n, k, l, a, m, b, m,
     $              alpha, beta, u, 1, v, 1, q, 1,
     $              work, m*n, rwork, iwork, info)
*
*     Print information there is a NAN in BETA
      DO 40 i = 1, l
         IF( beta(i).NE.beta(i) ) THEN
            info = -i
            EXIT
         END IF
   40 CONTINUE
      IF( info.LT.0 ) THEN
         IF( nfail.EQ.0 .AND. firstt ) THEN
            firstt = .false.
            CALL alahdg( nout, path )
         END IF
         WRITE( nout, fmt = 9997 ) -info
         nfail = nfail + 1
      END IF
      nrun = nrun + 1
      info = 0
*
*     Do for each value of M in MVAL.
*
      DO 30 im = 1, nm
         m = mval( im )
         p = pval( im )
         n = nval( im )
*
         DO 20 imat = 1, ntypes
*
*           Do the tests only if DOTYPE( IMAT ) is true.
*
            IF( .NOT.dotype( imat ) )
     $         GO TO 20
*
*           Set up parameters with SLATB9 and generate test
*           matrices A and B with CLATMS.
*
            CALL slatb9( path, imat, m, p, n, TYPE, kla, kua, klb, kub,
     $                   anorm, bnorm, modea, modeb, cndnma, cndnmb,
     $                   dista, distb )
*
*           Generate M by N matrix A
*
            CALL clatms( m, n, dista, iseed, TYPE, rwork, modea, cndnma,
     $                   anorm, kla, kua, 'No packing', a, lda, work,
     $                   iinfo )
            IF( iinfo.NE.0 ) THEN
               WRITE( nout, fmt = 9999 )iinfo
               info = abs( iinfo )
               GO TO 20
            END IF
*
*           Generate P by N matrix B
*
            CALL clatms( p, n, distb, iseed, TYPE, rwork, modeb, cndnmb,
     $                   bnorm, klb, kub, 'No packing', b, ldb, work,
     $                   iinfo )
            IF( iinfo.NE.0 ) THEN
               WRITE( nout, fmt = 9999 )iinfo
               info = abs( iinfo )
               GO TO 20
            END IF
*
            nt = 6
*
            CALL cgsvts3( m, p, n, a, af, lda, b, bf, ldb, u, ldu, v,
     $                    ldv, q, ldq, alpha, beta, r, ldr, iwork, work,
     $                    lwork, rwork, result )
*
*           Print information about the tests that did not
*           pass the threshold.
*
            DO 10 i = 1, nt
               IF( result( i ).GE.thresh ) THEN
                  IF( nfail.EQ.0 .AND. firstt ) THEN
                     firstt = .false.
                     CALL alahdg( nout, path )
                  END IF
                  WRITE( nout, fmt = 9998 )m, p, n, imat, i,
     $               result( i )
                  nfail = nfail + 1
               END IF
   10       CONTINUE
            nrun = nrun + nt
*
   20    CONTINUE
   30 CONTINUE
*
*     Print a summary of the results.
*
      CALL alasum( path, nout, nfail, nrun, 0 )
*
 9999 FORMAT( ' CLATMS in CCKGSV   INFO = ', i5 )
 9998 FORMAT( ' M=', i4, ' P=', i4, ', N=', i4, ', type ', i2,
     $      ', test ', i2, ', ratio=', g13.6 )
 9997 FORMAT( ' FOUND NaN in BETA(', i4,')' )
      RETURN
*
*     End of CCKGSV
*
      END