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version 1.8, 2011/07/22 07:38:10 version 1.9, 2011/11/21 20:43:02
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   *> \brief \b DPTCON
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download DPTCON + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dptcon.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dptcon.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dptcon.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DPTCON( N, D, E, ANORM, RCOND, WORK, INFO )
   * 
   *       .. Scalar Arguments ..
   *       INTEGER            INFO, N
   *       DOUBLE PRECISION   ANORM, RCOND
   *       ..
   *       .. Array Arguments ..
   *       DOUBLE PRECISION   D( * ), E( * ), WORK( * )
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DPTCON computes the reciprocal of the condition number (in the
   *> 1-norm) of a real symmetric positive definite tridiagonal matrix
   *> using the factorization A = L*D*L**T or A = U**T*D*U computed by
   *> DPTTRF.
   *>
   *> Norm(inv(A)) is computed by a direct method, and the reciprocal of
   *> the condition number is computed as
   *>              RCOND = 1 / (ANORM * norm(inv(A))).
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The order of the matrix A.  N >= 0.
   *> \endverbatim
   *>
   *> \param[in] D
   *> \verbatim
   *>          D is DOUBLE PRECISION array, dimension (N)
   *>          The n diagonal elements of the diagonal matrix D from the
   *>          factorization of A, as computed by DPTTRF.
   *> \endverbatim
   *>
   *> \param[in] E
   *> \verbatim
   *>          E is DOUBLE PRECISION array, dimension (N-1)
   *>          The (n-1) off-diagonal elements of the unit bidiagonal factor
   *>          U or L from the factorization of A,  as computed by DPTTRF.
   *> \endverbatim
   *>
   *> \param[in] ANORM
   *> \verbatim
   *>          ANORM is DOUBLE PRECISION
   *>          The 1-norm of the original matrix A.
   *> \endverbatim
   *>
   *> \param[out] RCOND
   *> \verbatim
   *>          RCOND is DOUBLE PRECISION
   *>          The reciprocal of the condition number of the matrix A,
   *>          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is the
   *>          1-norm of inv(A) computed in this routine.
   *> \endverbatim
   *>
   *> \param[out] WORK
   *> \verbatim
   *>          WORK is DOUBLE PRECISION array, dimension (N)
   *> \endverbatim
   *>
   *> \param[out] INFO
   *> \verbatim
   *>          INFO is INTEGER
   *>          = 0:  successful exit
   *>          < 0:  if INFO = -i, the i-th argument had an illegal value
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup doubleOTHERcomputational
   *
   *> \par Further Details:
   *  =====================
   *>
   *> \verbatim
   *>
   *>  The method used is described in Nicholas J. Higham, "Efficient
   *>  Algorithms for Computing the Condition Number of a Tridiagonal
   *>  Matrix", SIAM J. Sci. Stat. Comput., Vol. 7, No. 1, January 1986.
   *> \endverbatim
   *>
   *  =====================================================================
       SUBROUTINE DPTCON( N, D, E, ANORM, RCOND, WORK, INFO )        SUBROUTINE DPTCON( N, D, E, ANORM, RCOND, WORK, INFO )
 *  *
 *  -- LAPACK routine (version 3.3.1) --  *  -- LAPACK computational routine (version 3.4.0) --
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
 *  -- April 2011                                                      --  *     November 2011
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       INTEGER            INFO, N        INTEGER            INFO, N
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       DOUBLE PRECISION   D( * ), E( * ), WORK( * )        DOUBLE PRECISION   D( * ), E( * ), WORK( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DPTCON computes the reciprocal of the condition number (in the  
 *  1-norm) of a real symmetric positive definite tridiagonal matrix  
 *  using the factorization A = L*D*L**T or A = U**T*D*U computed by  
 *  DPTTRF.  
 *  
 *  Norm(inv(A)) is computed by a direct method, and the reciprocal of  
 *  the condition number is computed as  
 *               RCOND = 1 / (ANORM * norm(inv(A))).  
 *  
 *  Arguments  
 *  =========  
 *  
 *  N       (input) INTEGER  
 *          The order of the matrix A.  N >= 0.  
 *  
 *  D       (input) DOUBLE PRECISION array, dimension (N)  
 *          The n diagonal elements of the diagonal matrix D from the  
 *          factorization of A, as computed by DPTTRF.  
 *  
 *  E       (input) DOUBLE PRECISION array, dimension (N-1)  
 *          The (n-1) off-diagonal elements of the unit bidiagonal factor  
 *          U or L from the factorization of A,  as computed by DPTTRF.  
 *  
 *  ANORM   (input) DOUBLE PRECISION  
 *          The 1-norm of the original matrix A.  
 *  
 *  RCOND   (output) DOUBLE PRECISION  
 *          The reciprocal of the condition number of the matrix A,  
 *          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is the  
 *          1-norm of inv(A) computed in this routine.  
 *  
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (N)  
 *  
 *  INFO    (output) INTEGER  
 *          = 0:  successful exit  
 *          < 0:  if INFO = -i, the i-th argument had an illegal value  
 *  
 *  Further Details  
 *  ===============  
 *  
 *  The method used is described in Nicholas J. Higham, "Efficient  
 *  Algorithms for Computing the Condition Number of a Tridiagonal  
 *  Matrix", SIAM J. Sci. Stat. Comput., Vol. 7, No. 1, January 1986.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.8  
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  Added in v.1.9

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