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*> \brief \b DGET06
*
* =========== DOCUMENTATION ===========
*
* Online html documentation available at
* http://www.netlib.org/lapack/explore-html/
*
* Definition:
* ===========
*
* DOUBLE PRECISION FUNCTION DGET06( RCOND, RCONDC )
*
* .. Scalar Arguments ..
* DOUBLE PRECISION RCOND, RCONDC
* ..
*
*
*> \par Purpose:
* =============
*>
*> \verbatim
*>
*> DGET06 computes a test ratio to compare two values for RCOND.
*> \endverbatim
*
* Arguments:
* ==========
*
*> \param[in] RCOND
*> \verbatim
*> RCOND is DOUBLE PRECISION
*> The estimate of the reciprocal of the condition number of A,
*> as computed by DGECON.
*> \endverbatim
*>
*> \param[in] RCONDC
*> \verbatim
*> RCONDC is DOUBLE PRECISION
*> 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 double_lin
*
* =====================================================================
DOUBLE PRECISION FUNCTION DGET06( 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 ..
DOUBLE PRECISION RCOND, RCONDC
* ..
*
* =====================================================================
*
* .. 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
|
