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Diff for /rpl/lapack/lapack/dstev.f between versions 1.1.1.1 and 1.17

version 1.1.1.1, 2010/01/26 15:22:45 version 1.17, 2023/08/07 08:39:07
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   *> \brief <b> DSTEV computes the eigenvalues and, optionally, the left and/or right eigenvectors for OTHER matrices</b>
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at
   *            http://www.netlib.org/lapack/explore-html/
   *
   *> \htmlonly
   *> Download DSTEV + dependencies
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dstev.f">
   *> [TGZ]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dstev.f">
   *> [ZIP]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dstev.f">
   *> [TXT]</a>
   *> \endhtmlonly
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE DSTEV( JOBZ, N, D, E, Z, LDZ, WORK, INFO )
   *
   *       .. Scalar Arguments ..
   *       CHARACTER          JOBZ
   *       INTEGER            INFO, LDZ, N
   *       ..
   *       .. Array Arguments ..
   *       DOUBLE PRECISION   D( * ), E( * ), WORK( * ), Z( LDZ, * )
   *       ..
   *
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> DSTEV computes all eigenvalues and, optionally, eigenvectors of a
   *> real symmetric tridiagonal matrix A.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] JOBZ
   *> \verbatim
   *>          JOBZ is CHARACTER*1
   *>          = 'N':  Compute eigenvalues only;
   *>          = 'V':  Compute eigenvalues and eigenvectors.
   *> \endverbatim
   *>
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The order of the matrix.  N >= 0.
   *> \endverbatim
   *>
   *> \param[in,out] D
   *> \verbatim
   *>          D is DOUBLE PRECISION array, dimension (N)
   *>          On entry, the n diagonal elements of the tridiagonal matrix
   *>          A.
   *>          On exit, if INFO = 0, the eigenvalues in ascending order.
   *> \endverbatim
   *>
   *> \param[in,out] E
   *> \verbatim
   *>          E is DOUBLE PRECISION array, dimension (N-1)
   *>          On entry, the (n-1) subdiagonal elements of the tridiagonal
   *>          matrix A, stored in elements 1 to N-1 of E.
   *>          On exit, the contents of E are destroyed.
   *> \endverbatim
   *>
   *> \param[out] Z
   *> \verbatim
   *>          Z is DOUBLE PRECISION array, dimension (LDZ, N)
   *>          If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal
   *>          eigenvectors of the matrix A, with the i-th column of Z
   *>          holding the eigenvector associated with D(i).
   *>          If JOBZ = 'N', then Z is not referenced.
   *> \endverbatim
   *>
   *> \param[in] LDZ
   *> \verbatim
   *>          LDZ is INTEGER
   *>          The leading dimension of the array Z.  LDZ >= 1, and if
   *>          JOBZ = 'V', LDZ >= max(1,N).
   *> \endverbatim
   *>
   *> \param[out] WORK
   *> \verbatim
   *>          WORK is DOUBLE PRECISION array, dimension (max(1,2*N-2))
   *>          If JOBZ = 'N', WORK is not referenced.
   *> \endverbatim
   *>
   *> \param[out] INFO
   *> \verbatim
   *>          INFO is INTEGER
   *>          = 0:  successful exit
   *>          < 0:  if INFO = -i, the i-th argument had an illegal value
   *>          > 0:  if INFO = i, the algorithm failed to converge; i
   *>                off-diagonal elements of E did not converge to zero.
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee
   *> \author Univ. of California Berkeley
   *> \author Univ. of Colorado Denver
   *> \author NAG Ltd.
   *
   *> \ingroup doubleOTHEReigen
   *
   *  =====================================================================
       SUBROUTINE DSTEV( JOBZ, N, D, E, Z, LDZ, WORK, INFO )        SUBROUTINE DSTEV( JOBZ, N, D, E, Z, LDZ, WORK, INFO )
 *  *
 *  -- LAPACK driver routine (version 3.2) --  *  -- LAPACK driver routine --
 *  -- 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  
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       CHARACTER          JOBZ        CHARACTER          JOBZ
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       DOUBLE PRECISION   D( * ), E( * ), WORK( * ), Z( LDZ, * )        DOUBLE PRECISION   D( * ), E( * ), WORK( * ), Z( LDZ, * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  DSTEV computes all eigenvalues and, optionally, eigenvectors of a  
 *  real symmetric tridiagonal matrix A.  
 *  
 *  Arguments  
 *  =========  
 *  
 *  JOBZ    (input) CHARACTER*1  
 *          = 'N':  Compute eigenvalues only;  
 *          = 'V':  Compute eigenvalues and eigenvectors.  
 *  
 *  N       (input) INTEGER  
 *          The order of the matrix.  N >= 0.  
 *  
 *  D       (input/output) DOUBLE PRECISION array, dimension (N)  
 *          On entry, the n diagonal elements of the tridiagonal matrix  
 *          A.  
 *          On exit, if INFO = 0, the eigenvalues in ascending order.  
 *  
 *  E       (input/output) DOUBLE PRECISION array, dimension (N-1)  
 *          On entry, the (n-1) subdiagonal elements of the tridiagonal  
 *          matrix A, stored in elements 1 to N-1 of E.  
 *          On exit, the contents of E are destroyed.  
 *  
 *  Z       (output) DOUBLE PRECISION array, dimension (LDZ, N)  
 *          If JOBZ = 'V', then if INFO = 0, Z contains the orthonormal  
 *          eigenvectors of the matrix A, with the i-th column of Z  
 *          holding the eigenvector associated with D(i).  
 *          If JOBZ = 'N', then Z is not referenced.  
 *  
 *  LDZ     (input) INTEGER  
 *          The leading dimension of the array Z.  LDZ >= 1, and if  
 *          JOBZ = 'V', LDZ >= max(1,N).  
 *  
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (max(1,2*N-2))  
 *          If JOBZ = 'N', WORK is not referenced.  
 *  
 *  INFO    (output) INTEGER  
 *          = 0:  successful exit  
 *          < 0:  if INFO = -i, the i-th argument had an illegal value  
 *          > 0:  if INFO = i, the algorithm failed to converge; i  
 *                off-diagonal elements of E did not converge to zero.  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Removed from v.1.1.1.1  
changed lines
  Added in v.1.17

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