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DOUBLE PRECISION FUNCTION DGET06( RCOND, RCONDC )
* * -- LAPACK test routine (version 3.1) -- * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. * November 2006 * * .. Scalar Arguments .. DOUBLE PRECISION RCOND, RCONDC * .. * * Purpose * ======= * * DGET06 computes a test ratio to compare two values for RCOND. * * Arguments * ========== * * RCOND (input) DOUBLE PRECISION * The estimate of the reciprocal of the condition number of A, * as computed by DGECON. * * RCONDC (input) DOUBLE PRECISION * The reciprocal of the condition number of A, computed as * ( 1/norm(A) ) / norm(inv(A)). * * ===================================================================== * * .. Parameters .. DOUBLE PRECISION ZERO, ONE PARAMETER ( ZERO = 0.0D+0, ONE = 1.0D+0 ) * .. * .. Local Scalars .. DOUBLE PRECISION EPS, RAT * .. * .. External Functions .. DOUBLE PRECISION DLAMCH EXTERNAL DLAMCH * .. * .. Intrinsic Functions .. INTRINSIC MAX, MIN * .. * .. Executable Statements .. * EPS = DLAMCH( 'Epsilon' ) IF( RCOND.GT.ZERO ) THEN IF( RCONDC.GT.ZERO ) THEN RAT = MAX( RCOND, RCONDC ) / MIN( RCOND, RCONDC ) - $ ( ONE-EPS ) ELSE RAT = RCOND / EPS END IF ELSE IF( RCONDC.GT.ZERO ) THEN RAT = RCONDC / EPS ELSE RAT = ZERO END IF END IF DGET06 = RAT RETURN * * End of DGET06 * END |