testdata/lapack/TESTING/EIG/schkbl.f
*> \brief \b SCHKBL
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* SUBROUTINE SCHKBL( NIN, NOUT )
*
* .. Scalar Arguments ..
* INTEGER NIN, NOUT
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> SCHKBL tests SGEBAL, a routine for balancing a general real
*> matrix and isolating some of its eigenvalues.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] NIN
*> \verbatim
*> NIN is INTEGER
*> The logical unit number for input. NIN > 0.
*> \endverbatim
*>
*> \param[in] NOUT
*> \verbatim
*> NOUT is INTEGER
*> The logical unit number for output. NOUT > 0.
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date December 2016
*
*> \ingroup single_eig
*
* =====================================================================
SUBROUTINE SCHKBL( NIN, NOUT )
*
* -- LAPACK test routine (version 3.7.0) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* December 2016
*
* .. Scalar Arguments ..
INTEGER NIN, NOUT
* ..
*
* ======================================================================
*
* .. Parameters ..
INTEGER LDA
PARAMETER ( LDA = 20 )
REAL ZERO
PARAMETER ( ZERO = 0.0E+0 )
* ..
* .. Local Scalars ..
INTEGER I, IHI, IHIIN, ILO, ILOIN, INFO, J, KNT, N,
$ NINFO
REAL ANORM, MEPS, RMAX, SFMIN, TEMP, VMAX
* ..
* .. Local Arrays ..
INTEGER LMAX( 3 )
REAL A( LDA, LDA ), AIN( LDA, LDA ), DUMMY( 1 ),
$ SCALE( LDA ), SCALIN( LDA )
* ..
* .. External Functions ..
REAL SLAMCH, SLANGE
EXTERNAL SLAMCH, SLANGE
* ..
* .. External Subroutines ..
EXTERNAL SGEBAL
* ..
* .. Intrinsic Functions ..
INTRINSIC ABS, MAX
* ..
* .. Executable Statements ..
*
LMAX( 1 ) = 0
LMAX( 2 ) = 0
LMAX( 3 ) = 0
NINFO = 0
KNT = 0
RMAX = ZERO
VMAX = ZERO
SFMIN = SLAMCH( 'S' )
MEPS = SLAMCH( 'E' )
*
10 CONTINUE
*
READ( NIN, FMT = * )N
IF( N.EQ.0 )
$ GO TO 70
DO 20 I = 1, N
READ( NIN, FMT = * )( A( I, J ), J = 1, N )
20 CONTINUE
*
READ( NIN, FMT = * )ILOIN, IHIIN
DO 30 I = 1, N
READ( NIN, FMT = * )( AIN( I, J ), J = 1, N )
30 CONTINUE
READ( NIN, FMT = * )( SCALIN( I ), I = 1, N )
*
ANORM = SLANGE( 'M', N, N, A, LDA, DUMMY )
KNT = KNT + 1
*
CALL SGEBAL( 'B', N, A, LDA, ILO, IHI, SCALE, INFO )
*
IF( INFO.NE.0 ) THEN
NINFO = NINFO + 1
LMAX( 1 ) = KNT
END IF
*
IF( ILO.NE.ILOIN .OR. IHI.NE.IHIIN ) THEN
NINFO = NINFO + 1
LMAX( 2 ) = KNT
END IF
*
DO 50 I = 1, N
DO 40 J = 1, N
TEMP = MAX( A( I, J ), AIN( I, J ) )
TEMP = MAX( TEMP, SFMIN )
VMAX = MAX( VMAX, ABS( A( I, J )-AIN( I, J ) ) / TEMP )
40 CONTINUE
50 CONTINUE
*
DO 60 I = 1, N
TEMP = MAX( SCALE( I ), SCALIN( I ) )
TEMP = MAX( TEMP, SFMIN )
VMAX = MAX( VMAX, ABS( SCALE( I )-SCALIN( I ) ) / TEMP )
60 CONTINUE
*
*
IF( VMAX.GT.RMAX ) THEN
LMAX( 3 ) = KNT
RMAX = VMAX
END IF
*
GO TO 10
*
70 CONTINUE
*
WRITE( NOUT, FMT = 9999 )
9999 FORMAT( 1X, '.. test output of SGEBAL .. ' )
*
WRITE( NOUT, FMT = 9998 )RMAX
9998 FORMAT( 1X, 'value of largest test error = ', E12.3 )
WRITE( NOUT, FMT = 9997 )LMAX( 1 )
9997 FORMAT( 1X, 'example number where info is not zero = ', I4 )
WRITE( NOUT, FMT = 9996 )LMAX( 2 )
9996 FORMAT( 1X, 'example number where ILO or IHI wrong = ', I4 )
WRITE( NOUT, FMT = 9995 )LMAX( 3 )
9995 FORMAT( 1X, 'example number having largest error = ', I4 )
WRITE( NOUT, FMT = 9994 )NINFO
9994 FORMAT( 1X, 'number of examples where info is not 0 = ', I4 )
WRITE( NOUT, FMT = 9993 )KNT
9993 FORMAT( 1X, 'total number of examples tested = ', I4 )
*
RETURN
*
* End of SCHKBL
*
END