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version 1.8, 2011/07/22 07:38:17 version 1.9, 2011/11/21 20:43:17
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   *> \brief \b ZLARFG
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download ZLARFG + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlarfg.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlarfg.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlarfg.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE ZLARFG( N, ALPHA, X, INCX, TAU )
   * 
   *       .. Scalar Arguments ..
   *       INTEGER            INCX, N
   *       COMPLEX*16         ALPHA, TAU
   *       ..
   *       .. Array Arguments ..
   *       COMPLEX*16         X( * )
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> ZLARFG generates a complex elementary reflector H of order n, such
   *> that
   *>
   *>       H**H * ( alpha ) = ( beta ),   H**H * H = I.
   *>              (   x   )   (   0  )
   *>
   *> where alpha and beta are scalars, with beta real, and x is an
   *> (n-1)-element complex vector. H is represented in the form
   *>
   *>       H = I - tau * ( 1 ) * ( 1 v**H ) ,
   *>                     ( v )
   *>
   *> where tau is a complex scalar and v is a complex (n-1)-element
   *> vector. Note that H is not hermitian.
   *>
   *> If the elements of x are all zero and alpha is real, then tau = 0
   *> and H is taken to be the unit matrix.
   *>
   *> Otherwise  1 <= real(tau) <= 2  and  abs(tau-1) <= 1 .
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The order of the elementary reflector.
   *> \endverbatim
   *>
   *> \param[in,out] ALPHA
   *> \verbatim
   *>          ALPHA is COMPLEX*16
   *>          On entry, the value alpha.
   *>          On exit, it is overwritten with the value beta.
   *> \endverbatim
   *>
   *> \param[in,out] X
   *> \verbatim
   *>          X is COMPLEX*16 array, dimension
   *>                         (1+(N-2)*abs(INCX))
   *>          On entry, the vector x.
   *>          On exit, it is overwritten with the vector v.
   *> \endverbatim
   *>
   *> \param[in] INCX
   *> \verbatim
   *>          INCX is INTEGER
   *>          The increment between elements of X. INCX > 0.
   *> \endverbatim
   *>
   *> \param[out] TAU
   *> \verbatim
   *>          TAU is COMPLEX*16
   *>          The value tau.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup complex16OTHERauxiliary
   *
   *  =====================================================================
       SUBROUTINE ZLARFG( N, ALPHA, X, INCX, TAU )        SUBROUTINE ZLARFG( N, ALPHA, X, INCX, TAU )
 *  *
 *  -- LAPACK auxiliary routine (version 3.3.1) --  *  -- LAPACK auxiliary 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            INCX, N        INTEGER            INCX, N
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       COMPLEX*16         X( * )        COMPLEX*16         X( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  ZLARFG generates a complex elementary reflector H of order n, such  
 *  that  
 *  
 *        H**H * ( alpha ) = ( beta ),   H**H * H = I.  
 *               (   x   )   (   0  )  
 *  
 *  where alpha and beta are scalars, with beta real, and x is an  
 *  (n-1)-element complex vector. H is represented in the form  
 *  
 *        H = I - tau * ( 1 ) * ( 1 v**H ) ,  
 *                      ( v )  
 *  
 *  where tau is a complex scalar and v is a complex (n-1)-element  
 *  vector. Note that H is not hermitian.  
 *  
 *  If the elements of x are all zero and alpha is real, then tau = 0  
 *  and H is taken to be the unit matrix.  
 *  
 *  Otherwise  1 <= real(tau) <= 2  and  abs(tau-1) <= 1 .  
 *  
 *  Arguments  
 *  =========  
 *  
 *  N       (input) INTEGER  
 *          The order of the elementary reflector.  
 *  
 *  ALPHA   (input/output) COMPLEX*16  
 *          On entry, the value alpha.  
 *          On exit, it is overwritten with the value beta.  
 *  
 *  X       (input/output) COMPLEX*16 array, dimension  
 *                         (1+(N-2)*abs(INCX))  
 *          On entry, the vector x.  
 *          On exit, it is overwritten with the vector v.  
 *  
 *  INCX    (input) INTEGER  
 *          The increment between elements of X. INCX > 0.  
 *  
 *  TAU     (output) COMPLEX*16  
 *          The value tau.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.8  
changed lines
  Added in v.1.9

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