SUBROUTINE SCHKGL( NIN, NOUT ) * * -- LAPACK test routine (version 3.1) -- * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. * November 2006 * * .. Scalar Arguments .. INTEGER NIN, NOUT * .. * * Purpose * ======= * * SCHKGL tests SGGBAL, a routine for balancing a matrix pair (A, B). * * Arguments * ========= * * NIN (input) INTEGER * The logical unit number for input. NIN > 0. * * NOUT (input) INTEGER * The logical unit number for output. NOUT > 0. * * ===================================================================== * * .. Parameters .. INTEGER LDA, LDB, LWORK PARAMETER ( LDA = 20, LDB = 20, LWORK = 6*LDA ) REAL ZERO PARAMETER ( ZERO = 0.0E+0 ) * .. * .. Local Scalars .. INTEGER I, IHI, IHIIN, ILO, ILOIN, INFO, J, KNT, N, $ NINFO REAL ANORM, BNORM, EPS, RMAX, VMAX * .. * .. Local Arrays .. INTEGER LMAX( 5 ) REAL A( LDA, LDA ), AIN( LDA, LDA ), B( LDB, LDB ), $ BIN( LDB, LDB ), LSCALE( LDA ), LSCLIN( LDA ), $ RSCALE( LDA ), RSCLIN( LDA ), WORK( LWORK ) * .. * .. External Functions .. REAL SLAMCH, SLANGE EXTERNAL SLAMCH, SLANGE * .. * .. External Subroutines .. EXTERNAL SGGBAL * .. * .. Intrinsic Functions .. INTRINSIC ABS, MAX * .. * .. Executable Statements .. * LMAX( 1 ) = 0 LMAX( 2 ) = 0 LMAX( 3 ) = 0 NINFO = 0 KNT = 0 RMAX = ZERO * EPS = SLAMCH( 'Precision' ) * 10 CONTINUE * READ( NIN, FMT = * )N IF( N.EQ.0 ) $ GO TO 90 DO 20 I = 1, N READ( NIN, FMT = * )( A( I, J ), J = 1, N ) 20 CONTINUE * DO 30 I = 1, N READ( NIN, FMT = * )( B( I, J ), J = 1, N ) 30 CONTINUE * READ( NIN, FMT = * )ILOIN, IHIIN DO 40 I = 1, N READ( NIN, FMT = * )( AIN( I, J ), J = 1, N ) 40 CONTINUE DO 50 I = 1, N READ( NIN, FMT = * )( BIN( I, J ), J = 1, N ) 50 CONTINUE * READ( NIN, FMT = * )( LSCLIN( I ), I = 1, N ) READ( NIN, FMT = * )( RSCLIN( I ), I = 1, N ) * ANORM = SLANGE( 'M', N, N, A, LDA, WORK ) BNORM = SLANGE( 'M', N, N, B, LDB, WORK ) * KNT = KNT + 1 * CALL SGGBAL( 'B', N, A, LDA, B, LDB, ILO, IHI, LSCALE, RSCALE, $ WORK, 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 * VMAX = ZERO DO 70 I = 1, N DO 60 J = 1, N VMAX = MAX( VMAX, ABS( A( I, J )-AIN( I, J ) ) ) VMAX = MAX( VMAX, ABS( B( I, J )-BIN( I, J ) ) ) 60 CONTINUE 70 CONTINUE * DO 80 I = 1, N VMAX = MAX( VMAX, ABS( LSCALE( I )-LSCLIN( I ) ) ) VMAX = MAX( VMAX, ABS( RSCALE( I )-RSCLIN( I ) ) ) 80 CONTINUE * VMAX = VMAX / ( EPS*MAX( ANORM, BNORM ) ) * IF( VMAX.GT.RMAX ) THEN LMAX( 3 ) = KNT RMAX = VMAX END IF * GO TO 10 * 90 CONTINUE * WRITE( NOUT, FMT = 9999 ) 9999 FORMAT( 1X, '.. test output of SGGBAL .. ' ) * 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 SCHKGL * END