dget06.f

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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.
*
*> \ingroup double_lin
*
*  =====================================================================
      DOUBLE PRECISION FUNCTION dget06( RCOND, RCONDC )
*
*  -- LAPACK test routine --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*
*     .. 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