SUBROUTINE CGET35( RMAX, LMAX, NINFO, KNT, NIN ) * * -- LAPACK test routine (version 3.1) -- * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. * November 2006 * * .. Scalar Arguments .. INTEGER KNT, LMAX, NIN, NINFO REAL RMAX * .. * * Purpose * ======= * * CGET35 tests CTRSYL, a routine for solving the Sylvester matrix * equation * * op(A)*X + ISGN*X*op(B) = scale*C, * * A and B are assumed to be in Schur canonical form, op() represents an * optional transpose, and ISGN can be -1 or +1. Scale is an output * less than or equal to 1, chosen to avoid overflow in X. * * The test code verifies that the following residual is order 1: * * norm(op(A)*X + ISGN*X*op(B) - scale*C) / * (EPS*max(norm(A),norm(B))*norm(X)) * * Arguments * ========== * * RMAX (output) REAL * Value of the largest test ratio. * * LMAX (output) INTEGER * Example number where largest test ratio achieved. * * NINFO (output) INTEGER * Number of examples where INFO is nonzero. * * KNT (output) INTEGER * Total number of examples tested. * * NIN (input) INTEGER * Input logical unit number. * * ===================================================================== * * .. Parameters .. INTEGER LDT PARAMETER ( LDT = 10 ) REAL ZERO, ONE, TWO PARAMETER ( ZERO = 0.0E0, ONE = 1.0E0, TWO = 2.0E0 ) REAL LARGE PARAMETER ( LARGE = 1.0E6 ) COMPLEX CONE PARAMETER ( CONE = 1.0E0 ) * .. * .. Local Scalars .. CHARACTER TRANA, TRANB INTEGER I, IMLA, IMLAD, IMLB, IMLC, INFO, ISGN, ITRANA, \$ ITRANB, J, M, N REAL BIGNUM, EPS, RES, RES1, SCALE, SMLNUM, TNRM, \$ XNRM COMPLEX RMUL * .. * .. Local Arrays .. REAL DUM( 1 ), VM1( 3 ), VM2( 3 ) COMPLEX A( LDT, LDT ), ATMP( LDT, LDT ), B( LDT, LDT ), \$ BTMP( LDT, LDT ), C( LDT, LDT ), \$ CSAV( LDT, LDT ), CTMP( LDT, LDT ) * .. * .. External Functions .. REAL CLANGE, SLAMCH EXTERNAL CLANGE, SLAMCH * .. * .. External Subroutines .. EXTERNAL CGEMM, CTRSYL * .. * .. Intrinsic Functions .. INTRINSIC ABS, MAX, REAL, SQRT * .. * .. Executable Statements .. * * Get machine parameters * EPS = SLAMCH( 'P' ) SMLNUM = SLAMCH( 'S' ) / EPS BIGNUM = ONE / SMLNUM CALL SLABAD( SMLNUM, BIGNUM ) * * Set up test case parameters * VM1( 1 ) = SQRT( SMLNUM ) VM1( 2 ) = ONE VM1( 3 ) = LARGE VM2( 1 ) = ONE VM2( 2 ) = ONE + TWO*EPS VM2( 3 ) = TWO * KNT = 0 NINFO = 0 LMAX = 0 RMAX = ZERO * * Begin test loop * 10 CONTINUE READ( NIN, FMT = * )M, N IF( N.EQ.0 ) \$ RETURN DO 20 I = 1, M READ( NIN, FMT = * )( ATMP( I, J ), J = 1, M ) 20 CONTINUE DO 30 I = 1, N READ( NIN, FMT = * )( BTMP( I, J ), J = 1, N ) 30 CONTINUE DO 40 I = 1, M READ( NIN, FMT = * )( CTMP( I, J ), J = 1, N ) 40 CONTINUE DO 170 IMLA = 1, 3 DO 160 IMLAD = 1, 3 DO 150 IMLB = 1, 3 DO 140 IMLC = 1, 3 DO 130 ITRANA = 1, 2 DO 120 ITRANB = 1, 2 DO 110 ISGN = -1, 1, 2 IF( ITRANA.EQ.1 ) \$ TRANA = 'N' IF( ITRANA.EQ.2 ) \$ TRANA = 'C' IF( ITRANB.EQ.1 ) \$ TRANB = 'N' IF( ITRANB.EQ.2 ) \$ TRANB = 'C' TNRM = ZERO DO 60 I = 1, M DO 50 J = 1, M A( I, J ) = ATMP( I, J )*VM1( IMLA ) TNRM = MAX( TNRM, ABS( A( I, J ) ) ) 50 CONTINUE A( I, I ) = A( I, I )*VM2( IMLAD ) TNRM = MAX( TNRM, ABS( A( I, I ) ) ) 60 CONTINUE DO 80 I = 1, N DO 70 J = 1, N B( I, J ) = BTMP( I, J )*VM1( IMLB ) TNRM = MAX( TNRM, ABS( B( I, J ) ) ) 70 CONTINUE 80 CONTINUE IF( TNRM.EQ.ZERO ) \$ TNRM = ONE DO 100 I = 1, M DO 90 J = 1, N C( I, J ) = CTMP( I, J )*VM1( IMLC ) CSAV( I, J ) = C( I, J ) 90 CONTINUE 100 CONTINUE KNT = KNT + 1 CALL CTRSYL( TRANA, TRANB, ISGN, M, N, A, \$ LDT, B, LDT, C, LDT, SCALE, \$ INFO ) IF( INFO.NE.0 ) \$ NINFO = NINFO + 1 XNRM = CLANGE( 'M', M, N, C, LDT, DUM ) RMUL = CONE IF( XNRM.GT.ONE .AND. TNRM.GT.ONE ) THEN IF( XNRM.GT.BIGNUM / TNRM ) THEN RMUL = MAX( XNRM, TNRM ) RMUL = CONE / RMUL END IF END IF CALL CGEMM( TRANA, 'N', M, N, M, RMUL, A, \$ LDT, C, LDT, -SCALE*RMUL, CSAV, \$ LDT ) CALL CGEMM( 'N', TRANB, M, N, N, \$ REAL( ISGN )*RMUL, C, LDT, B, \$ LDT, CONE, CSAV, LDT ) RES1 = CLANGE( 'M', M, N, CSAV, LDT, DUM ) RES = RES1 / MAX( SMLNUM, SMLNUM*XNRM, \$ ( ( ABS( RMUL )*TNRM )*EPS )*XNRM ) IF( RES.GT.RMAX ) THEN LMAX = KNT RMAX = RES END IF 110 CONTINUE 120 CONTINUE 130 CONTINUE 140 CONTINUE 150 CONTINUE 160 CONTINUE 170 CONTINUE GO TO 10 * * End of CGET35 * END