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-version 1.8, 2011/07/22 07:38:17
+version 1.9, 2011/11/21 20:43:15
  Line 1
+ *> \brief \b ZLAESY
+ *
+ *  =========== DOCUMENTATION ===========
+ *
+ * Online html documentation available at
+ *            http://www.netlib.org/lapack/explore-html/
+ *
+ *> \htmlonly
+ *> Download ZLAESY + dependencies
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlaesy.f">
+ *> [TGZ]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlaesy.f">
+ *> [ZIP]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlaesy.f">
+ *> [TXT]</a>
+ *> \endhtmlonly
+ *
+ *  Definition:
+ *  ===========
+ *
+ *       SUBROUTINE ZLAESY( A, B, C, RT1, RT2, EVSCAL, CS1, SN1 )
+ *
+ *       .. Scalar Arguments ..
+ *       COMPLEX*16         A, B, C, CS1, EVSCAL, RT1, RT2, SN1
+ *       ..
+ *
+ *
+ *> \par Purpose:
+ *  =============
+ *>
+ *> \verbatim
+ *>
+ *> ZLAESY computes the eigendecomposition of a 2-by-2 symmetric matrix
+ *>    ( ( A, B );( B, C ) )
+ *> provided the norm of the matrix of eigenvectors is larger than
+ *> some threshold value.
+ *>
+ *> RT1 is the eigenvalue of larger absolute value, and RT2 of
+ *> smaller absolute value.  If the eigenvectors are computed, then
+ *> on return ( CS1, SN1 ) is the unit eigenvector for RT1, hence
+ *>
+ *> [  CS1     SN1   ] . [ A  B ] . [ CS1    -SN1   ] = [ RT1  0  ]
+ *> [ -SN1     CS1   ]   [ B  C ]   [ SN1     CS1   ]   [  0  RT2 ]
+ *> \endverbatim
+ *
+ *  Arguments:
+ *  ==========
+ *
+ *> \param[in] A
+ *> \verbatim
+ *>          A is COMPLEX*16
+ *>          The ( 1, 1 ) element of input matrix.
+ *> \endverbatim
+ *>
+ *> \param[in] B
+ *> \verbatim
+ *>          B is COMPLEX*16
+ *>          The ( 1, 2 ) element of input matrix.  The ( 2, 1 ) element
+ *>          is also given by B, since the 2-by-2 matrix is symmetric.
+ *> \endverbatim
+ *>
+ *> \param[in] C
+ *> \verbatim
+ *>          C is COMPLEX*16
+ *>          The ( 2, 2 ) element of input matrix.
+ *> \endverbatim
+ *>
+ *> \param[out] RT1
+ *> \verbatim
+ *>          RT1 is COMPLEX*16
+ *>          The eigenvalue of larger modulus.
+ *> \endverbatim
+ *>
+ *> \param[out] RT2
+ *> \verbatim
+ *>          RT2 is COMPLEX*16
+ *>          The eigenvalue of smaller modulus.
+ *> \endverbatim
+ *>
+ *> \param[out] EVSCAL
+ *> \verbatim
+ *>          EVSCAL is COMPLEX*16
+ *>          The complex value by which the eigenvector matrix was scaled
+ *>          to make it orthonormal.  If EVSCAL is zero, the eigenvectors
+ *>          were not computed.  This means one of two things:  the 2-by-2
+ *>          matrix could not be diagonalized, or the norm of the matrix
+ *>          of eigenvectors before scaling was larger than the threshold
+ *>          value THRESH (set below).
+ *> \endverbatim
+ *>
+ *> \param[out] CS1
+ *> \verbatim
+ *>          CS1 is COMPLEX*16
+ *> \endverbatim
+ *>
+ *> \param[out] SN1
+ *> \verbatim
+ *>          SN1 is COMPLEX*16
+ *>          If EVSCAL .NE. 0,  ( CS1, SN1 ) is the unit right eigenvector
+ *>          for RT1.
+ *> \endverbatim
+ *
+ *  Authors:
+ *  ========
+ *
+ *> \author Univ. of Tennessee
+ *> \author Univ. of California Berkeley
+ *> \author Univ. of Colorado Denver
+ *> \author NAG Ltd.
+ *
+ *> \date November 2011
+ *
+ *> \ingroup complex16SYauxiliary
+ *
+ *  =====================================================================
        SUBROUTINE ZLAESY( A, B, C, RT1, RT2, EVSCAL, CS1, SN1 )
  *
- *  -- LAPACK auxiliary routine (version 3.2) --
+ *  -- LAPACK auxiliary routine (version 3.4.0) --
  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
- *     November 2006
+ *     November 2011
  *
  *     .. Scalar Arguments ..
        COMPLEX*16         A, B, C, CS1, EVSCAL, RT1, RT2, SN1
  *     ..
  *
- *  Purpose
- *  =======
- *
- *  ZLAESY computes the eigendecomposition of a 2-by-2 symmetric matrix
- *     ( ( A, B );( B, C ) )
- *  provided the norm of the matrix of eigenvectors is larger than
- *  some threshold value.
- *
- *  RT1 is the eigenvalue of larger absolute value, and RT2 of
- *  smaller absolute value.  If the eigenvectors are computed, then
- *  on return ( CS1, SN1 ) is the unit eigenvector for RT1, hence
- *
- *  [  CS1     SN1   ] . [ A  B ] . [ CS1    -SN1   ] = [ RT1  0  ]
- *  [ -SN1     CS1   ]   [ B  C ]   [ SN1     CS1   ]   [  0  RT2 ]
- *
- *  Arguments
- *  =========
- *
- *  A       (input) COMPLEX*16
- *          The ( 1, 1 ) element of input matrix.
- *
- *  B       (input) COMPLEX*16
- *          The ( 1, 2 ) element of input matrix.  The ( 2, 1 ) element
- *          is also given by B, since the 2-by-2 matrix is symmetric.
- *
- *  C       (input) COMPLEX*16
- *          The ( 2, 2 ) element of input matrix.
- *
- *  RT1     (output) COMPLEX*16
- *          The eigenvalue of larger modulus.
- *
- *  RT2     (output) COMPLEX*16
- *          The eigenvalue of smaller modulus.
- *
- *  EVSCAL  (output) COMPLEX*16
- *          The complex value by which the eigenvector matrix was scaled
- *          to make it orthonormal.  If EVSCAL is zero, the eigenvectors
- *          were not computed.  This means one of two things:  the 2-by-2
- *          matrix could not be diagonalized, or the norm of the matrix
- *          of eigenvectors before scaling was larger than the threshold
- *          value THRESH (set below).
- *
- *  CS1     (output) COMPLEX*16
- *  SN1     (output) COMPLEX*16
- *          If EVSCAL .NE. 0,  ( CS1, SN1 ) is the unit right eigenvector
- *          for RT1.
- *
  * =====================================================================
  *
  *     .. Parameters ..

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