|
1
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 |
SUBROUTINE SCHKGK( 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 * ======= * * SCHKGK tests SGGBAK, a routine for backward balancing of * 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, LDVL, LDVR PARAMETER ( LDA = 50, LDB = 50, LDVL = 50, LDVR = 50 ) INTEGER LDE, LDF, LDWORK PARAMETER ( LDE = 50, LDF = 50, LDWORK = 50 ) REAL ZERO, ONE PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 ) * .. * .. Local Scalars .. INTEGER I, IHI, ILO, INFO, J, KNT, M, N, NINFO REAL ANORM, BNORM, EPS, RMAX, VMAX * .. * .. Local Arrays .. INTEGER LMAX( 4 ) REAL A( LDA, LDA ), AF( LDA, LDA ), B( LDB, LDB ), $ BF( LDB, LDB ), E( LDE, LDE ), F( LDF, LDF ), $ LSCALE( LDA ), RSCALE( LDA ), VL( LDVL, LDVL ), $ VLF( LDVL, LDVL ), VR( LDVR, LDVR ), $ VRF( LDVR, LDVR ), WORK( LDWORK, LDWORK ) * .. * .. External Functions .. REAL SLAMCH, SLANGE EXTERNAL SLAMCH, SLANGE * .. * .. External Subroutines .. EXTERNAL SGEMM, SGGBAK, SGGBAL, SLACPY * .. * .. Intrinsic Functions .. INTRINSIC ABS, MAX * .. * .. Executable Statements .. * * Initialization * LMAX( 1 ) = 0 LMAX( 2 ) = 0 LMAX( 3 ) = 0 LMAX( 4 ) = 0 NINFO = 0 KNT = 0 RMAX = ZERO * EPS = SLAMCH( 'Precision' ) * 10 CONTINUE READ( NIN, FMT = * )N, M IF( N.EQ.0 ) $ GO TO 100 * 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 * DO 40 I = 1, N READ( NIN, FMT = * )( VL( I, J ), J = 1, M ) 40 CONTINUE * DO 50 I = 1, N READ( NIN, FMT = * )( VR( I, J ), J = 1, M ) 50 CONTINUE * KNT = KNT + 1 * ANORM = SLANGE( 'M', N, N, A, LDA, WORK ) BNORM = SLANGE( 'M', N, N, B, LDB, WORK ) * CALL SLACPY( 'FULL', N, N, A, LDA, AF, LDA ) CALL SLACPY( 'FULL', N, N, B, LDB, BF, LDB ) * 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 * CALL SLACPY( 'FULL', N, M, VL, LDVL, VLF, LDVL ) CALL SLACPY( 'FULL', N, M, VR, LDVR, VRF, LDVR ) * CALL SGGBAK( 'B', 'L', N, ILO, IHI, LSCALE, RSCALE, M, VL, LDVL, $ INFO ) IF( INFO.NE.0 ) THEN NINFO = NINFO + 1 LMAX( 2 ) = KNT END IF * CALL SGGBAK( 'B', 'R', N, ILO, IHI, LSCALE, RSCALE, M, VR, LDVR, $ INFO ) IF( INFO.NE.0 ) THEN NINFO = NINFO + 1 LMAX( 3 ) = KNT END IF * * Test of SGGBAK * * Check tilde(VL)'*A*tilde(VR) - VL'*tilde(A)*VR * where tilde(A) denotes the transformed matrix. * CALL SGEMM( 'N', 'N', N, M, N, ONE, AF, LDA, VR, LDVR, ZERO, WORK, $ LDWORK ) CALL SGEMM( 'T', 'N', M, M, N, ONE, VL, LDVL, WORK, LDWORK, ZERO, $ E, LDE ) * CALL SGEMM( 'N', 'N', N, M, N, ONE, A, LDA, VRF, LDVR, ZERO, WORK, $ LDWORK ) CALL SGEMM( 'T', 'N', M, M, N, ONE, VLF, LDVL, WORK, LDWORK, ZERO, $ F, LDF ) * VMAX = ZERO DO 70 J = 1, M DO 60 I = 1, M VMAX = MAX( VMAX, ABS( E( I, J )-F( I, J ) ) ) 60 CONTINUE 70 CONTINUE VMAX = VMAX / ( EPS*MAX( ANORM, BNORM ) ) IF( VMAX.GT.RMAX ) THEN LMAX( 4 ) = KNT RMAX = VMAX END IF * * Check tilde(VL)'*B*tilde(VR) - VL'*tilde(B)*VR * CALL SGEMM( 'N', 'N', N, M, N, ONE, BF, LDB, VR, LDVR, ZERO, WORK, $ LDWORK ) CALL SGEMM( 'T', 'N', M, M, N, ONE, VL, LDVL, WORK, LDWORK, ZERO, $ E, LDE ) * CALL SGEMM( 'N', 'N', N, M, N, ONE, B, LDB, VRF, LDVR, ZERO, WORK, $ LDWORK ) CALL SGEMM( 'T', 'N', M, M, N, ONE, VLF, LDVL, WORK, LDWORK, ZERO, $ F, LDF ) * VMAX = ZERO DO 90 J = 1, M DO 80 I = 1, M VMAX = MAX( VMAX, ABS( E( I, J )-F( I, J ) ) ) 80 CONTINUE 90 CONTINUE VMAX = VMAX / ( EPS*MAX( ANORM, BNORM ) ) IF( VMAX.GT.RMAX ) THEN LMAX( 4 ) = KNT RMAX = VMAX END IF * GO TO 10 * 100 CONTINUE * WRITE( NOUT, FMT = 9999 ) 9999 FORMAT( 1X, '.. test output of SGGBAK .. ' ) * WRITE( NOUT, FMT = 9998 )RMAX 9998 FORMAT( ' value of largest test error =', E12.3 ) WRITE( NOUT, FMT = 9997 )LMAX( 1 ) 9997 FORMAT( ' example number where SGGBAL info is not 0 =', I4 ) WRITE( NOUT, FMT = 9996 )LMAX( 2 ) 9996 FORMAT( ' example number where SGGBAK(L) info is not 0 =', I4 ) WRITE( NOUT, FMT = 9995 )LMAX( 3 ) 9995 FORMAT( ' example number where SGGBAK(R) info is not 0 =', I4 ) WRITE( NOUT, FMT = 9994 )LMAX( 4 ) 9994 FORMAT( ' example number having largest error =', I4 ) WRITE( NOUT, FMT = 9992 )NINFO 9992 FORMAT( ' number of examples where info is not 0 =', I4 ) WRITE( NOUT, FMT = 9991 )KNT 9991 FORMAT( ' total number of examples tested =', I4 ) * RETURN * * End of SCHKGK * END |