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version 1.7, 2010/12/21 13:53:32 version 1.8, 2011/11/21 20:42:58
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   *> \brief \b DLAS2
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at 
   *            http://www.netlib.org/lapack/explore-html/ 
   *
   *> \htmlonly
   *> Download DLAS2 + dependencies 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlas2.f"> 
   *> [TGZ]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlas2.f"> 
   *> [ZIP]</a> 
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlas2.f"> 
   *> [TXT]</a>
   *> \endhtmlonly 
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DLAS2( F, G, H, SSMIN, SSMAX )
   * 
   *       .. Scalar Arguments ..
   *       DOUBLE PRECISION   F, G, H, SSMAX, SSMIN
   *       ..
   *  
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DLAS2  computes the singular values of the 2-by-2 matrix
   *>    [  F   G  ]
   *>    [  0   H  ].
   *> On return, SSMIN is the smaller singular value and SSMAX is the
   *> larger singular value.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] F
   *> \verbatim
   *>          F is DOUBLE PRECISION
   *>          The (1,1) element of the 2-by-2 matrix.
   *> \endverbatim
   *>
   *> \param[in] G
   *> \verbatim
   *>          G is DOUBLE PRECISION
   *>          The (1,2) element of the 2-by-2 matrix.
   *> \endverbatim
   *>
   *> \param[in] H
   *> \verbatim
   *>          H is DOUBLE PRECISION
   *>          The (2,2) element of the 2-by-2 matrix.
   *> \endverbatim
   *>
   *> \param[out] SSMIN
   *> \verbatim
   *>          SSMIN is DOUBLE PRECISION
   *>          The smaller singular value.
   *> \endverbatim
   *>
   *> \param[out] SSMAX
   *> \verbatim
   *>          SSMAX is DOUBLE PRECISION
   *>          The larger singular value.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee 
   *> \author Univ. of California Berkeley 
   *> \author Univ. of Colorado Denver 
   *> \author NAG Ltd. 
   *
   *> \date November 2011
   *
   *> \ingroup auxOTHERauxiliary
   *
   *> \par Further Details:
   *  =====================
   *>
   *> \verbatim
   *>
   *>  Barring over/underflow, all output quantities are correct to within
   *>  a few units in the last place (ulps), even in the absence of a guard
   *>  digit in addition/subtraction.
   *>
   *>  In IEEE arithmetic, the code works correctly if one matrix element is
   *>  infinite.
   *>
   *>  Overflow will not occur unless the largest singular value itself
   *>  overflows, or is within a few ulps of overflow. (On machines with
   *>  partial overflow, like the Cray, overflow may occur if the largest
   *>  singular value is within a factor of 2 of overflow.)
   *>
   *>  Underflow is harmless if underflow is gradual. Otherwise, results
   *>  may correspond to a matrix modified by perturbations of size near
   *>  the underflow threshold.
   *> \endverbatim
   *>
   *  =====================================================================
       SUBROUTINE DLAS2( F, G, H, SSMIN, SSMAX )        SUBROUTINE DLAS2( F, G, H, SSMIN, SSMAX )
 *  *
 *  -- 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   F, G, H, SSMAX, SSMIN        DOUBLE PRECISION   F, G, H, SSMAX, SSMIN
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DLAS2  computes the singular values of the 2-by-2 matrix  
 *     [  F   G  ]  
 *     [  0   H  ].  
 *  On return, SSMIN is the smaller singular value and SSMAX is the  
 *  larger singular value.  
 *  
 *  Arguments  
 *  =========  
 *  
 *  F       (input) DOUBLE PRECISION  
 *          The (1,1) element of the 2-by-2 matrix.  
 *  
 *  G       (input) DOUBLE PRECISION  
 *          The (1,2) element of the 2-by-2 matrix.  
 *  
 *  H       (input) DOUBLE PRECISION  
 *          The (2,2) element of the 2-by-2 matrix.  
 *  
 *  SSMIN   (output) DOUBLE PRECISION  
 *          The smaller singular value.  
 *  
 *  SSMAX   (output) DOUBLE PRECISION  
 *          The larger singular value.  
 *  
 *  Further Details  
 *  ===============  
 *  
 *  Barring over/underflow, all output quantities are correct to within  
 *  a few units in the last place (ulps), even in the absence of a guard  
 *  digit in addition/subtraction.  
 *  
 *  In IEEE arithmetic, the code works correctly if one matrix element is  
 *  infinite.  
 *  
 *  Overflow will not occur unless the largest singular value itself  
 *  overflows, or is within a few ulps of overflow. (On machines with  
 *  partial overflow, like the Cray, overflow may occur if the largest  
 *  singular value is within a factor of 2 of overflow.)  
 *  
 *  Underflow is harmless if underflow is gradual. Otherwise, results  
 *  may correspond to a matrix modified by perturbations of size near  
 *  the underflow threshold.  
 *  
 *  ====================================================================  *  ====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.7  
changed lines
  Added in v.1.8

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