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-version 1.1, 2010/12/21 13:50:36
+version 1.5, 2011/11/21 22:19:34
  Line 1
-       SUBROUTINE DLARTGS( X, Y, SIGMA, CS, SN )
+ *> \brief \b DLARTGS
-       IMPLICIT NONE
- *
- *  -- LAPACK routine (version 3.3.0) --
- *
- *  -- Contributed by Brian Sutton of the Randolph-Macon College --
- *  -- November 2010
- *
- *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
- *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
- *
- *     .. Scalar Arguments ..
-       DOUBLE PRECISION        CS, SIGMA, SN, X, Y
- *     ..
- *
- *  Purpose
- *  =======
  *
- *  DLARTGS generates a plane rotation designed to introduce a bulge in
+ *  =========== DOCUMENTATION ===========
- *  Golub-Reinsch-style implicit QR iteration for the bidiagonal SVD
- *  problem. X and Y are the top-row entries, and SIGMA is the shift.
- *  The computed CS and SN define a plane rotation satisfying
  *
- *     [  CS  SN  ]  .  [ X^2 - SIGMA ]  =  [ R ],
+ * Online html documentation available at
- *     [ -SN  CS  ]     [    X * Y    ]     [ 0 ]
+ *            http://www.netlib.org/lapack/explore-html/
  *
- *  with R nonnegative.  If X^2 - SIGMA and X * Y are 0, then the
+ *> \htmlonly
- *  rotation is by PI/2.
+ *> Download DLARTGS + dependencies
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlartgs.f">
+ *> [TGZ]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlartgs.f">
+ *> [ZIP]</a>
+ *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlartgs.f">
+ *> [TXT]</a>
+ *> \endhtmlonly
+ *
+ *  Definition:
+ *  ===========
+ *
+ *       SUBROUTINE DLARTGS( X, Y, SIGMA, CS, SN )
+ *
+ *       .. Scalar Arguments ..
+ *       DOUBLE PRECISION        CS, SIGMA, SN, X, Y
+ *       ..
+ *
+ *
+ *> \par Purpose:
+ *  =============
+ *>
+ *> \verbatim
+ *>
+ *> DLARTGS generates a plane rotation designed to introduce a bulge in
+ *> Golub-Reinsch-style implicit QR iteration for the bidiagonal SVD
+ *> problem. X and Y are the top-row entries, and SIGMA is the shift.
+ *> The computed CS and SN define a plane rotation satisfying
+ *>
+ *>    [  CS  SN  ]  .  [ X^2 - SIGMA ]  =  [ R ],
+ *>    [ -SN  CS  ]     [    X * Y    ]     [ 0 ]
+ *>
+ *> with R nonnegative.  If X^2 - SIGMA and X * Y are 0, then the
+ *> rotation is by PI/2.
+ *> \endverbatim
+ *
+ *  Arguments:
+ *  ==========
+ *
+ *> \param[in] X
+ *> \verbatim
+ *>          X is DOUBLE PRECISION
+ *>          The (1,1) entry of an upper bidiagonal matrix.
+ *> \endverbatim
+ *>
+ *> \param[in] Y
+ *> \verbatim
+ *>          Y is DOUBLE PRECISION
+ *>          The (1,2) entry of an upper bidiagonal matrix.
+ *> \endverbatim
+ *>
+ *> \param[in] SIGMA
+ *> \verbatim
+ *>          SIGMA is DOUBLE PRECISION
+ *>          The shift.
+ *> \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
+ *
+ *  Authors:
+ *  ========
+ *
+ *> \author Univ. of Tennessee
+ *> \author Univ. of California Berkeley
+ *> \author Univ. of Colorado Denver
+ *> \author NAG Ltd.
  *
- *  Arguments
+ *> \date November 2011
- *  =========
  *
- *  X       (input) DOUBLE PRECISION
+ *> \ingroup auxOTHERcomputational
- *          The (1,1) entry of an upper bidiagonal matrix.
  *
- *  Y       (input) DOUBLE PRECISION
+ *  =====================================================================
- *          The (1,2) entry of an upper bidiagonal matrix.
+       SUBROUTINE DLARTGS( X, Y, SIGMA, CS, SN )
- *
- *  SIGMA   (input) DOUBLE PRECISION
- *          The shift.
  *
- *  CS      (output) DOUBLE PRECISION
+ *  -- LAPACK computational routine (version 3.4.0) --
- *          The cosine of the rotation.
+ *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
+ *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
+ *     November 2011
  *
- *  SN      (output) DOUBLE PRECISION
+ *     .. Scalar Arguments ..
- *          The sine of the rotation.
+       DOUBLE PRECISION        CS, SIGMA, SN, X, Y
+ *     ..
  *
  *  ===================================================================
  *
- Line 61
+ Line 115
  *
        THRESH = DLAMCH('E')
  *
- *     Compute the first column of B'*B - SIGMA^2*I, up to a scale
+ *     Compute the first column of B**T*B - SIGMA^2*I, up to a scale
  *     factor.
  *
        IF( (SIGMA .EQ. ZERO .AND. ABS(X) .LT. THRESH) .OR.

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