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REAL FUNCTION SGET06( RCOND, RCONDC )
* * -- LAPACK test routine (version 3.1) -- * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. * November 2006 * * .. Scalar Arguments .. REAL RCOND, RCONDC * .. * * Purpose * ======= * * SGET06 computes a test ratio to compare two values for RCOND. * * Arguments * ========== * * RCOND (input) REAL * The estimate of the reciprocal of the condition number of A, * as computed by SGECON. * * RCONDC (input) REAL * The reciprocal of the condition number of A, computed as * ( 1/norm(A) ) / norm(inv(A)). * * ===================================================================== * * .. Parameters .. REAL ZERO, ONE PARAMETER ( ZERO = 0.0E+0, ONE = 1.0E+0 ) * .. * .. Local Scalars .. REAL EPS, RAT * .. * .. External Functions .. REAL SLAMCH EXTERNAL SLAMCH * .. * .. Intrinsic Functions .. INTRINSIC MAX, MIN * .. * .. Executable Statements .. * EPS = SLAMCH( '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 SGET06 = RAT RETURN * * End of SGET06 * END |