Diff for /rpl/lapack/lapack/dlaqr1.f between versions 1.7 and 1.8

version 1.7, 2010/12/21 13:53:31 version 1.8, 2011/11/21 20:42:56
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   *> \brief \b DLAQR1
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download DLAQR1 + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlaqr1.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlaqr1.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlaqr1.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DLAQR1( N, H, LDH, SR1, SI1, SR2, SI2, V )
   * 
   *       .. Scalar Arguments ..
   *       DOUBLE PRECISION   SI1, SI2, SR1, SR2
   *       INTEGER            LDH, N
   *       ..
   *       .. Array Arguments ..
   *       DOUBLE PRECISION   H( LDH, * ), V( * )
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *>      Given a 2-by-2 or 3-by-3 matrix H, DLAQR1 sets v to a
   *>      scalar multiple of the first column of the product
   *>
   *>      (*)  K = (H - (sr1 + i*si1)*I)*(H - (sr2 + i*si2)*I)
   *>
   *>      scaling to avoid overflows and most underflows. It
   *>      is assumed that either
   *>
   *>              1) sr1 = sr2 and si1 = -si2
   *>          or
   *>              2) si1 = si2 = 0.
   *>
   *>      This is useful for starting double implicit shift bulges
   *>      in the QR algorithm.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] N
   *> \verbatim
   *>          N is integer
   *>              Order of the matrix H. N must be either 2 or 3.
   *> \endverbatim
   *>
   *> \param[in] H
   *> \verbatim
   *>          H is DOUBLE PRECISION array of dimension (LDH,N)
   *>              The 2-by-2 or 3-by-3 matrix H in (*).
   *> \endverbatim
   *>
   *> \param[in] LDH
   *> \verbatim
   *>          LDH is integer
   *>              The leading dimension of H as declared in
   *>              the calling procedure.  LDH.GE.N
   *> \endverbatim
   *>
   *> \param[in] SR1
   *> \verbatim
   *>          SR1 is DOUBLE PRECISION
   *> \endverbatim
   *>
   *> \param[in] SI1
   *> \verbatim
   *>          SI1 is DOUBLE PRECISION
   *> \endverbatim
   *>
   *> \param[in] SR2
   *> \verbatim
   *>          SR2 is DOUBLE PRECISION
   *> \endverbatim
   *>
   *> \param[in] SI2
   *> \verbatim
   *>          SI2 is DOUBLE PRECISION
   *>              The shifts in (*).
   *> \endverbatim
   *>
   *> \param[out] V
   *> \verbatim
   *>          V is DOUBLE PRECISION array of dimension N
   *>              A scalar multiple of the first column of the
   *>              matrix K in (*).
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup doubleOTHERauxiliary
   *
   *> \par Contributors:
   *  ==================
   *>
   *>       Karen Braman and Ralph Byers, Department of Mathematics,
   *>       University of Kansas, USA
   *>
   *  =====================================================================
       SUBROUTINE DLAQR1( N, H, LDH, SR1, SI1, SR2, SI2, V )        SUBROUTINE DLAQR1( N, H, LDH, SR1, SI1, SR2, SI2, V )
 *  *
 *  -- LAPACK auxiliary routine (version 3.2) --  *  -- LAPACK auxiliary routine (version 3.4.0) --
 *     Univ. of Tennessee, Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
 *     November 2006  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   *     November 2011
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       DOUBLE PRECISION   SI1, SI2, SR1, SR2        DOUBLE PRECISION   SI1, SI2, SR1, SR2
Line 12 Line 134
       DOUBLE PRECISION   H( LDH, * ), V( * )        DOUBLE PRECISION   H( LDH, * ), V( * )
 *     ..  *     ..
 *  *
 *       Given a 2-by-2 or 3-by-3 matrix H, DLAQR1 sets v to a  *  ================================================================
 *       scalar multiple of the first column of the product  
 *  
 *       (*)  K = (H - (sr1 + i*si1)*I)*(H - (sr2 + i*si2)*I)  
 *  
 *       scaling to avoid overflows and most underflows. It  
 *       is assumed that either  
 *  
 *               1) sr1 = sr2 and si1 = -si2  
 *           or  
 *               2) si1 = si2 = 0.  
 *  
 *       This is useful for starting double implicit shift bulges  
 *       in the QR algorithm.  
 *  
 *  
 *       N      (input) integer  
 *              Order of the matrix H. N must be either 2 or 3.  
 *  
 *       H      (input) DOUBLE PRECISION array of dimension (LDH,N)  
 *              The 2-by-2 or 3-by-3 matrix H in (*).  
 *  
 *       LDH    (input) integer  
 *              The leading dimension of H as declared in  
 *              the calling procedure.  LDH.GE.N  
 *  
 *       SR1    (input) DOUBLE PRECISION  
 *       SI1    The shifts in (*).  
 *       SR2  
 *       SI2  
 *  
 *       V      (output) DOUBLE PRECISION array of dimension N  
 *              A scalar multiple of the first column of the  
 *              matrix K in (*).  
 *  
 *     ================================================================  
 *     Based on contributions by  
 *        Karen Braman and Ralph Byers, Department of Mathematics,  
 *        University of Kansas, USA  
 *  
 *     ================================================================  
 *  *
 *     .. Parameters ..  *     .. Parameters ..
       DOUBLE PRECISION   ZERO        DOUBLE PRECISION   ZERO

Removed from v.1.7  
changed lines
  Added in v.1.8


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