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version 1.7, 2010/12/21 13:53:52 version 1.8, 2011/11/21 20:43:17
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   *> \brief \b ZLARTG
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download ZLARTG + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlartg.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlartg.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlartg.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE ZLARTG( F, G, CS, SN, R )
   * 
   *       .. Scalar Arguments ..
   *       DOUBLE PRECISION   CS
   *       COMPLEX*16         F, G, R, SN
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> ZLARTG generates a plane rotation so that
   *>
   *>    [  CS  SN  ]     [ F ]     [ R ]
   *>    [  __      ]  .  [   ]  =  [   ]   where CS**2 + |SN|**2 = 1.
   *>    [ -SN  CS  ]     [ G ]     [ 0 ]
   *>
   *> This is a faster version of the BLAS1 routine ZROTG, except for
   *> the following differences:
   *>    F and G are unchanged on return.
   *>    If G=0, then CS=1 and SN=0.
   *>    If F=0, then CS=0 and SN is chosen so that R is real.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] F
   *> \verbatim
   *>          F is COMPLEX*16
   *>          The first component of vector to be rotated.
   *> \endverbatim
   *>
   *> \param[in] G
   *> \verbatim
   *>          G is COMPLEX*16
   *>          The second component of vector to be rotated.
   *> \endverbatim
   *>
   *> \param[out] CS
   *> \verbatim
   *>          CS is DOUBLE PRECISION
   *>          The cosine of the rotation.
   *> \endverbatim
   *>
   *> \param[out] SN
   *> \verbatim
   *>          SN is COMPLEX*16
   *>          The sine of the rotation.
   *> \endverbatim
   *>
   *> \param[out] R
   *> \verbatim
   *>          R is COMPLEX*16
   *>          The nonzero component of the rotated vector.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup complex16OTHERauxiliary
   *
   *> \par Further Details:
   *  =====================
   *>
   *> \verbatim
   *>
   *>  3-5-96 - Modified with a new algorithm by W. Kahan and J. Demmel
   *>
   *>  This version has a few statements commented out for thread safety
   *>  (machine parameters are computed on each entry). 10 feb 03, SJH.
   *> \endverbatim
   *>
   *  =====================================================================
       SUBROUTINE ZLARTG( F, G, CS, SN, R )        SUBROUTINE ZLARTG( F, G, CS, SN, R )
 *  *
 *  -- LAPACK auxiliary routine (version 3.2) --  *  -- 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..--
 *     November 2006  *     November 2011
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       DOUBLE PRECISION   CS        DOUBLE PRECISION   CS
       COMPLEX*16         F, G, R, SN        COMPLEX*16         F, G, R, SN
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  ZLARTG generates a plane rotation so that  
 *  
 *     [  CS  SN  ]     [ F ]     [ R ]  
 *     [  __      ]  .  [   ]  =  [   ]   where CS**2 + |SN|**2 = 1.  
 *     [ -SN  CS  ]     [ G ]     [ 0 ]  
 *  
 *  This is a faster version of the BLAS1 routine ZROTG, except for  
 *  the following differences:  
 *     F and G are unchanged on return.  
 *     If G=0, then CS=1 and SN=0.  
 *     If F=0, then CS=0 and SN is chosen so that R is real.  
 *  
 *  Arguments  
 *  =========  
 *  
 *  F       (input) COMPLEX*16  
 *          The first component of vector to be rotated.  
 *  
 *  G       (input) COMPLEX*16  
 *          The second component of vector to be rotated.  
 *  
 *  CS      (output) DOUBLE PRECISION  
 *          The cosine of the rotation.  
 *  
 *  SN      (output) COMPLEX*16  
 *          The sine of the rotation.  
 *  
 *  R       (output) COMPLEX*16  
 *          The nonzero component of the rotated vector.  
 *  
 *  Further Details  
 *  ======= =======  
 *  
 *  3-5-96 - Modified with a new algorithm by W. Kahan and J. Demmel  
 *  
 *  This version has a few statements commented out for thread safety  
 *  (machine parameters are computed on each entry). 10 feb 03, SJH.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.7  
changed lines
  Added in v.1.8

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