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LAPACK
3.4.1
LAPACK: Linear Algebra PACKage
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00001 *> \brief \b SCHKBL 00002 * 00003 * =========== DOCUMENTATION =========== 00004 * 00005 * Online html documentation available at 00006 * http://www.netlib.org/lapack/explore-html/ 00007 * 00008 * Definition: 00009 * =========== 00010 * 00011 * SUBROUTINE SCHKBL( NIN, NOUT ) 00012 * 00013 * .. Scalar Arguments .. 00014 * INTEGER NIN, NOUT 00015 * .. 00016 * 00017 * 00018 *> \par Purpose: 00019 * ============= 00020 *> 00021 *> \verbatim 00022 *> 00023 *> SCHKBL tests SGEBAL, a routine for balancing a general real 00024 *> matrix and isolating some of its eigenvalues. 00025 *> \endverbatim 00026 * 00027 * Arguments: 00028 * ========== 00029 * 00030 *> \param[in] NIN 00031 *> \verbatim 00032 *> NIN is INTEGER 00033 *> The logical unit number for input. NIN > 0. 00034 *> \endverbatim 00035 *> 00036 *> \param[in] NOUT 00037 *> \verbatim 00038 *> NOUT is INTEGER 00039 *> The logical unit number for output. NOUT > 0. 00040 *> \endverbatim 00041 * 00042 * Authors: 00043 * ======== 00044 * 00045 *> \author Univ. of Tennessee 00046 *> \author Univ. of California Berkeley 00047 *> \author Univ. of Colorado Denver 00048 *> \author NAG Ltd. 00049 * 00050 *> \date November 2011 00051 * 00052 *> \ingroup single_eig 00053 * 00054 * ===================================================================== 00055 SUBROUTINE SCHKBL( NIN, NOUT ) 00056 * 00057 * -- LAPACK test routine (version 3.4.0) -- 00058 * -- LAPACK is a software package provided by Univ. of Tennessee, -- 00059 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 00060 * November 2011 00061 * 00062 * .. Scalar Arguments .. 00063 INTEGER NIN, NOUT 00064 * .. 00065 * 00066 * ====================================================================== 00067 * 00068 * .. Parameters .. 00069 INTEGER LDA 00070 PARAMETER ( LDA = 20 ) 00071 REAL ZERO 00072 PARAMETER ( ZERO = 0.0E+0 ) 00073 * .. 00074 * .. Local Scalars .. 00075 INTEGER I, IHI, IHIIN, ILO, ILOIN, INFO, J, KNT, N, 00076 $ NINFO 00077 REAL ANORM, MEPS, RMAX, SFMIN, TEMP, VMAX 00078 * .. 00079 * .. Local Arrays .. 00080 INTEGER LMAX( 3 ) 00081 REAL A( LDA, LDA ), AIN( LDA, LDA ), DUMMY( 1 ), 00082 $ SCALE( LDA ), SCALIN( LDA ) 00083 * .. 00084 * .. External Functions .. 00085 REAL SLAMCH, SLANGE 00086 EXTERNAL SLAMCH, SLANGE 00087 * .. 00088 * .. External Subroutines .. 00089 EXTERNAL SGEBAL 00090 * .. 00091 * .. Intrinsic Functions .. 00092 INTRINSIC ABS, MAX 00093 * .. 00094 * .. Executable Statements .. 00095 * 00096 LMAX( 1 ) = 0 00097 LMAX( 2 ) = 0 00098 LMAX( 3 ) = 0 00099 NINFO = 0 00100 KNT = 0 00101 RMAX = ZERO 00102 VMAX = ZERO 00103 SFMIN = SLAMCH( 'S' ) 00104 MEPS = SLAMCH( 'E' ) 00105 * 00106 10 CONTINUE 00107 * 00108 READ( NIN, FMT = * )N 00109 IF( N.EQ.0 ) 00110 $ GO TO 70 00111 DO 20 I = 1, N 00112 READ( NIN, FMT = * )( A( I, J ), J = 1, N ) 00113 20 CONTINUE 00114 * 00115 READ( NIN, FMT = * )ILOIN, IHIIN 00116 DO 30 I = 1, N 00117 READ( NIN, FMT = * )( AIN( I, J ), J = 1, N ) 00118 30 CONTINUE 00119 READ( NIN, FMT = * )( SCALIN( I ), I = 1, N ) 00120 * 00121 ANORM = SLANGE( 'M', N, N, A, LDA, DUMMY ) 00122 KNT = KNT + 1 00123 * 00124 CALL SGEBAL( 'B', N, A, LDA, ILO, IHI, SCALE, INFO ) 00125 * 00126 IF( INFO.NE.0 ) THEN 00127 NINFO = NINFO + 1 00128 LMAX( 1 ) = KNT 00129 END IF 00130 * 00131 IF( ILO.NE.ILOIN .OR. IHI.NE.IHIIN ) THEN 00132 NINFO = NINFO + 1 00133 LMAX( 2 ) = KNT 00134 END IF 00135 * 00136 DO 50 I = 1, N 00137 DO 40 J = 1, N 00138 TEMP = MAX( A( I, J ), AIN( I, J ) ) 00139 TEMP = MAX( TEMP, SFMIN ) 00140 VMAX = MAX( VMAX, ABS( A( I, J )-AIN( I, J ) ) / TEMP ) 00141 40 CONTINUE 00142 50 CONTINUE 00143 * 00144 DO 60 I = 1, N 00145 TEMP = MAX( SCALE( I ), SCALIN( I ) ) 00146 TEMP = MAX( TEMP, SFMIN ) 00147 VMAX = MAX( VMAX, ABS( SCALE( I )-SCALIN( I ) ) / TEMP ) 00148 60 CONTINUE 00149 * 00150 * 00151 IF( VMAX.GT.RMAX ) THEN 00152 LMAX( 3 ) = KNT 00153 RMAX = VMAX 00154 END IF 00155 * 00156 GO TO 10 00157 * 00158 70 CONTINUE 00159 * 00160 WRITE( NOUT, FMT = 9999 ) 00161 9999 FORMAT( 1X, '.. test output of SGEBAL .. ' ) 00162 * 00163 WRITE( NOUT, FMT = 9998 )RMAX 00164 9998 FORMAT( 1X, 'value of largest test error = ', E12.3 ) 00165 WRITE( NOUT, FMT = 9997 )LMAX( 1 ) 00166 9997 FORMAT( 1X, 'example number where info is not zero = ', I4 ) 00167 WRITE( NOUT, FMT = 9996 )LMAX( 2 ) 00168 9996 FORMAT( 1X, 'example number where ILO or IHI wrong = ', I4 ) 00169 WRITE( NOUT, FMT = 9995 )LMAX( 3 ) 00170 9995 FORMAT( 1X, 'example number having largest error = ', I4 ) 00171 WRITE( NOUT, FMT = 9994 )NINFO 00172 9994 FORMAT( 1X, 'number of examples where info is not 0 = ', I4 ) 00173 WRITE( NOUT, FMT = 9993 )KNT 00174 9993 FORMAT( 1X, 'total number of examples tested = ', I4 ) 00175 * 00176 RETURN 00177 * 00178 * End of SCHKBL 00179 * 00180 END