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-version 1.2, 2010/04/21 13:45:19
+version 1.13, 2014/01/27 09:28:22
  Line 1
+ *> \brief \b DLASD5 computes the square root of the i-th eigenvalue of a positive symmetric rank-one modification of a 2-by-2 diagonal matrix. Used by sbdsdc.
+ *
+ *  =========== DOCUMENTATION ===========
+ *
+ * Online html documentation available at
+ *            http://www.netlib.org/lapack/explore-html/
+ *
+ *> \htmlonly
+ *> Download DLASD5 + dependencies
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlasd5.f">
+ *> [TGZ]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlasd5.f">
+ *> [ZIP]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlasd5.f">
+ *> [TXT]</a>
+ *> \endhtmlonly
+ *
+ *  Definition:
+ *  ===========
+ *
+ *       SUBROUTINE DLASD5( I, D, Z, DELTA, RHO, DSIGMA, WORK )
+ *
+ *       .. Scalar Arguments ..
+ *       INTEGER            I
+ *       DOUBLE PRECISION   DSIGMA, RHO
+ *       ..
+ *       .. Array Arguments ..
+ *       DOUBLE PRECISION   D( 2 ), DELTA( 2 ), WORK( 2 ), Z( 2 )
+ *       ..
+ *
+ *
+ *> \par Purpose:
+ *  =============
+ *>
+ *> \verbatim
+ *>
+ *> This subroutine computes the square root of the I-th eigenvalue
+ *> of a positive symmetric rank-one modification of a 2-by-2 diagonal
+ *> matrix
+ *>
+ *>            diag( D ) * diag( D ) +  RHO * Z * transpose(Z) .
+ *>
+ *> The diagonal entries in the array D are assumed to satisfy
+ *>
+ *>            0 <= D(i) < D(j)  for  i < j .
+ *>
+ *> We also assume RHO > 0 and that the Euclidean norm of the vector
+ *> Z is one.
+ *> \endverbatim
+ *
+ *  Arguments:
+ *  ==========
+ *
+ *> \param[in] I
+ *> \verbatim
+ *>          I is INTEGER
+ *>         The index of the eigenvalue to be computed.  I = 1 or I = 2.
+ *> \endverbatim
+ *>
+ *> \param[in] D
+ *> \verbatim
+ *>          D is DOUBLE PRECISION array, dimension ( 2 )
+ *>         The original eigenvalues.  We assume 0 <= D(1) < D(2).
+ *> \endverbatim
+ *>
+ *> \param[in] Z
+ *> \verbatim
+ *>          Z is DOUBLE PRECISION array, dimension ( 2 )
+ *>         The components of the updating vector.
+ *> \endverbatim
+ *>
+ *> \param[out] DELTA
+ *> \verbatim
+ *>          DELTA is DOUBLE PRECISION array, dimension ( 2 )
+ *>         Contains (D(j) - sigma_I) in its  j-th component.
+ *>         The vector DELTA contains the information necessary
+ *>         to construct the eigenvectors.
+ *> \endverbatim
+ *>
+ *> \param[in] RHO
+ *> \verbatim
+ *>          RHO is DOUBLE PRECISION
+ *>         The scalar in the symmetric updating formula.
+ *> \endverbatim
+ *>
+ *> \param[out] DSIGMA
+ *> \verbatim
+ *>          DSIGMA is DOUBLE PRECISION
+ *>         The computed sigma_I, the I-th updated eigenvalue.
+ *> \endverbatim
+ *>
+ *> \param[out] WORK
+ *> \verbatim
+ *>          WORK is DOUBLE PRECISION array, dimension ( 2 )
+ *>         WORK contains (D(j) + sigma_I) in its  j-th component.
+ *> \endverbatim
+ *
+ *  Authors:
+ *  ========
+ *
+ *> \author Univ. of Tennessee
+ *> \author Univ. of California Berkeley
+ *> \author Univ. of Colorado Denver
+ *> \author NAG Ltd.
+ *
+ *> \date September 2012
+ *
+ *> \ingroup auxOTHERauxiliary
+ *
+ *> \par Contributors:
+ *  ==================
+ *>
+ *>     Ren-Cang Li, Computer Science Division, University of California
+ *>     at Berkeley, USA
+ *>
+ *  =====================================================================
        SUBROUTINE DLASD5( I, D, Z, DELTA, RHO, DSIGMA, WORK )
  *
- *  -- LAPACK auxiliary routine (version 3.2) --
+ *  -- LAPACK auxiliary routine (version 3.4.2) --
  *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
- *     November 2006
+ *     September 2012
  *
  *     .. Scalar Arguments ..
        INTEGER            I
- Line 13
+ Line 129
        DOUBLE PRECISION   D( 2 ), DELTA( 2 ), WORK( 2 ), Z( 2 )
  *     ..
  *
- *  Purpose
- *  =======
- *
- *  This subroutine computes the square root of the I-th eigenvalue
- *  of a positive symmetric rank-one modification of a 2-by-2 diagonal
- *  matrix
- *
- *             diag( D ) * diag( D ) +  RHO *  Z * transpose(Z) .
- *
- *  The diagonal entries in the array D are assumed to satisfy
- *
- *             0 <= D(i) < D(j)  for  i < j .
- *
- *  We also assume RHO > 0 and that the Euclidean norm of the vector
- *  Z is one.
- *
- *  Arguments
- *  =========
- *
- *  I      (input) INTEGER
- *         The index of the eigenvalue to be computed.  I = 1 or I = 2.
- *
- *  D      (input) DOUBLE PRECISION array, dimension ( 2 )
- *         The original eigenvalues.  We assume 0 <= D(1) < D(2).
- *
- *  Z      (input) DOUBLE PRECISION array, dimension ( 2 )
- *         The components of the updating vector.
- *
- *  DELTA  (output) DOUBLE PRECISION array, dimension ( 2 )
- *         Contains (D(j) - sigma_I) in its  j-th component.
- *         The vector DELTA contains the information necessary
- *         to construct the eigenvectors.
- *
- *  RHO    (input) DOUBLE PRECISION
- *         The scalar in the symmetric updating formula.
- *
- *  DSIGMA (output) DOUBLE PRECISION
- *         The computed sigma_I, the I-th updated eigenvalue.
- *
- *  WORK   (workspace) DOUBLE PRECISION array, dimension ( 2 )
- *         WORK contains (D(j) + sigma_I) in its  j-th component.
- *
- *  Further Details
- *  ===============
- *
- *  Based on contributions by
- *     Ren-Cang Li, Computer Science Division, University of California
- *     at Berkeley, USA
- *
  *  =====================================================================
  *
  *     .. Parameters ..

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