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Diff for /rpl/lapack/lapack/dpttrf.f between versions 1.8 and 1.9

version 1.8, 2011/07/22 07:38:10 version 1.9, 2011/11/21 20:43:02
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   *> \brief \b DPTTRF
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download DPTTRF + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dpttrf.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dpttrf.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dpttrf.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DPTTRF( N, D, E, INFO )
   * 
   *       .. Scalar Arguments ..
   *       INTEGER            INFO, N
   *       ..
   *       .. Array Arguments ..
   *       DOUBLE PRECISION   D( * ), E( * )
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DPTTRF computes the L*D*L**T factorization of a real symmetric
   *> positive definite tridiagonal matrix A.  The factorization may also
   *> be regarded as having the form A = U**T*D*U.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The order of the matrix A.  N >= 0.
   *> \endverbatim
   *>
   *> \param[in,out] D
   *> \verbatim
   *>          D is DOUBLE PRECISION array, dimension (N)
   *>          On entry, the n diagonal elements of the tridiagonal matrix
   *>          A.  On exit, the n diagonal elements of the diagonal matrix
   *>          D from the L*D*L**T factorization of A.
   *> \endverbatim
   *>
   *> \param[in,out] E
   *> \verbatim
   *>          E is DOUBLE PRECISION array, dimension (N-1)
   *>          On entry, the (n-1) subdiagonal elements of the tridiagonal
   *>          matrix A.  On exit, the (n-1) subdiagonal elements of the
   *>          unit bidiagonal factor L from the L*D*L**T factorization of A.
   *>          E can also be regarded as the superdiagonal of the unit
   *>          bidiagonal factor U from the U**T*D*U factorization of A.
   *> \endverbatim
   *>
   *> \param[out] INFO
   *> \verbatim
   *>          INFO is INTEGER
   *>          = 0: successful exit
   *>          < 0: if INFO = -k, the k-th argument had an illegal value
   *>          > 0: if INFO = k, the leading minor of order k is not
   *>               positive definite; if k < N, the factorization could not
   *>               be completed, while if k = N, the factorization was
   *>               completed, but D(N) <= 0.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup auxOTHERcomputational
   *
   *  =====================================================================
       SUBROUTINE DPTTRF( N, D, E, INFO )        SUBROUTINE DPTTRF( N, D, E, 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( * )        DOUBLE PRECISION   D( * ), E( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DPTTRF computes the L*D*L**T factorization of a real symmetric  
 *  positive definite tridiagonal matrix A.  The factorization may also  
 *  be regarded as having the form A = U**T*D*U.  
 *  
 *  Arguments  
 *  =========  
 *  
 *  N       (input) INTEGER  
 *          The order of the matrix A.  N >= 0.  
 *  
 *  D       (input/output) DOUBLE PRECISION array, dimension (N)  
 *          On entry, the n diagonal elements of the tridiagonal matrix  
 *          A.  On exit, the n diagonal elements of the diagonal matrix  
 *          D from the L*D*L**T factorization of A.  
 *  
 *  E       (input/output) DOUBLE PRECISION array, dimension (N-1)  
 *          On entry, the (n-1) subdiagonal elements of the tridiagonal  
 *          matrix A.  On exit, the (n-1) subdiagonal elements of the  
 *          unit bidiagonal factor L from the L*D*L**T factorization of A.  
 *          E can also be regarded as the superdiagonal of the unit  
 *          bidiagonal factor U from the U**T*D*U factorization of A.  
 *  
 *  INFO    (output) INTEGER  
 *          = 0: successful exit  
 *          < 0: if INFO = -k, the k-th argument had an illegal value  
 *          > 0: if INFO = k, the leading minor of order k is not  
 *               positive definite; if k < N, the factorization could not  
 *               be completed, while if k = N, the factorization was  
 *               completed, but D(N) <= 0.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.8  
changed lines
  Added in v.1.9

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