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Diff for /rpl/lapack/lapack/dlartgp.f between versions 1.3 and 1.4

version 1.3, 2011/07/22 07:40:26 version 1.4, 2011/11/21 20:42:58
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       SUBROUTINE DLARTGP( F, G, CS, SN, R )  *> \brief \b DLARTGP
 *  
 *     Originally DLARTG  
 *  -- LAPACK auxiliary routine (version 3.2) --  
 *  -- LAPACK is a software package provided by Univ. of Tennessee,    --  
 *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--  
 *     November 2006  
 *  
 *     Adapted to DLARTGP  
 *     July 2010  
 *  
 *     .. Scalar Arguments ..  
       DOUBLE PRECISION   CS, F, G, R, SN  
 *     ..  
 *  
 *  Purpose  
 *  =======  
 *  *
 *  DLARTGP generates a plane rotation so that  *  =========== DOCUMENTATION ===========
 *  *
 *     [  CS  SN  ]  .  [ F ]  =  [ R ]   where CS**2 + SN**2 = 1.  * Online html documentation available at 
 *     [ -SN  CS  ]     [ G ]     [ 0 ]  *            http://www.netlib.org/lapack/explore-html/ 
 *  *
 *  This is a slower, more accurate version of the Level 1 BLAS routine DROTG,  *> \htmlonly
 *  with the following other differences:  *> Download DLARTGP + dependencies 
 *     F and G are unchanged on return.  *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlartgp.f"> 
 *     If G=0, then CS=(+/-)1 and SN=0.  *> [TGZ]</a> 
 *     If F=0 and (G .ne. 0), then CS=0 and SN=(+/-)1.  *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlartgp.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlartgp.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DLARTGP( F, G, CS, SN, R )
   * 
   *       .. Scalar Arguments ..
   *       DOUBLE PRECISION   CS, F, G, R, SN
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DLARTGP generates a plane rotation so that
   *>
   *>    [  CS  SN  ]  .  [ F ]  =  [ R ]   where CS**2 + SN**2 = 1.
   *>    [ -SN  CS  ]     [ G ]     [ 0 ]
   *>
   *> This is a slower, more accurate version of the Level 1 BLAS routine DROTG,
   *> with the following other differences:
   *>    F and G are unchanged on return.
   *>    If G=0, then CS=(+/-)1 and SN=0.
   *>    If F=0 and (G .ne. 0), then CS=0 and SN=(+/-)1.
   *>
   *> The sign is chosen so that R >= 0.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] F
   *> \verbatim
   *>          F is DOUBLE PRECISION
   *>          The first component of vector to be rotated.
   *> \endverbatim
   *>
   *> \param[in] G
   *> \verbatim
   *>          G is DOUBLE PRECISION
   *>          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 DOUBLE PRECISION
   *>          The sine of the rotation.
   *> \endverbatim
   *>
   *> \param[out] R
   *> \verbatim
   *>          R is DOUBLE PRECISION
   *>          The nonzero component of the rotated vector.
   *>
   *>  This version has a few statements commented out for thread safety
   *>  (machine parameters are computed on each entry). 10 feb 03, SJH.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
 *  *
 *  The sign is chosen so that R >= 0.  *> \date November 2011
 *  *
 *  Arguments  *> \ingroup auxOTHERauxiliary
 *  =========  
 *  *
 *  F       (input) DOUBLE PRECISION  *  =====================================================================
 *          The first component of vector to be rotated.        SUBROUTINE DLARTGP( F, G, CS, SN, R )
 *  
 *  G       (input) DOUBLE PRECISION  
 *          The second component of vector to be rotated.  
 *  
 *  CS      (output) DOUBLE PRECISION  
 *          The cosine of the rotation.  
 *  
 *  SN      (output) DOUBLE PRECISION  
 *          The sine of the rotation.  
 *  *
 *  R       (output) DOUBLE PRECISION  *  -- LAPACK auxiliary routine (version 3.4.0) --
 *          The nonzero component of the rotated vector.  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
   *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
   *     November 2011
 *  *
 *  This version has a few statements commented out for thread safety  *     .. Scalar Arguments ..
 *  (machine parameters are computed on each entry). 10 feb 03, SJH.        DOUBLE PRECISION   CS, F, G, R, SN
   *     ..
 *  *
 *  =====================================================================  *  =====================================================================
 *  *
Removed from v.1.3  
changed lines
  Added in v.1.4

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