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*> \brief \b SGET06
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* REAL FUNCTION SGET06( RCOND, RCONDC )
*
* .. Scalar Arguments ..
* REAL RCOND, RCONDC
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> SGET06 computes a test ratio to compare two values for RCOND.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] RCOND
*> \verbatim
*> RCOND is REAL
*> The estimate of the reciprocal of the condition number of A,
*> as computed by SGECON.
*> \endverbatim
*>
*> \param[in] RCONDC
*> \verbatim
*> RCONDC is REAL
*> The reciprocal of the condition number of A, computed as
*> ( 1/norm(A) ) / norm(inv(A)).
*> \endverbatim
*
* Authors:
* ========
*
*> \author Univ. of Tennessee
*> \author Univ. of California Berkeley
*> \author Univ. of Colorado Denver
*> \author NAG Ltd.
*
*> \date November 2011
*
*> \ingroup single_lin
*
* =====================================================================
REAL FUNCTION SGET06( RCOND, RCONDC )
*
* -- LAPACK test routine (version 3.4.0) --
* -- LAPACK is a software package provided by Univ. of Tennessee, --
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
* November 2011
*
* .. Scalar Arguments ..
REAL RCOND, RCONDC
* ..
*
* =====================================================================
*
* .. 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
|
