[BACK]Return to zlarz.f CVS log [TXT] [DIR] Up to [local] / rpl / lapack / lapack

Diff for /rpl/lapack/lapack/zlarz.f between versions 1.5 and 1.18

version 1.5, 2010/08/07 13:22:41 version 1.18, 2018/05/29 07:18:29
Line 1 Line 1
   *> \brief \b ZLARZ applies an elementary reflector (as returned by stzrzf) to a general matrix.
   *
   *  =========== DOCUMENTATION ===========
   *
   * Online html documentation available at
   *            http://www.netlib.org/lapack/explore-html/
   *
   *> \htmlonly
   *> Download ZLARZ + dependencies
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlarz.f">
   *> [TGZ]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlarz.f">
   *> [ZIP]</a>
   *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlarz.f">
   *> [TXT]</a>
   *> \endhtmlonly
   *
   *  Definition:
   *  ===========
   *
   *       SUBROUTINE ZLARZ( SIDE, M, N, L, V, INCV, TAU, C, LDC, WORK )
   *
   *       .. Scalar Arguments ..
   *       CHARACTER          SIDE
   *       INTEGER            INCV, L, LDC, M, N
   *       COMPLEX*16         TAU
   *       ..
   *       .. Array Arguments ..
   *       COMPLEX*16         C( LDC, * ), V( * ), WORK( * )
   *       ..
   *
   *
   *> \par Purpose:
   *  =============
   *>
   *> \verbatim
   *>
   *> ZLARZ applies a complex elementary reflector H to a complex
   *> M-by-N matrix C, from either the left or the right. H is represented
   *> in the form
   *>
   *>       H = I - tau * v * v**H
   *>
   *> where tau is a complex scalar and v is a complex vector.
   *>
   *> If tau = 0, then H is taken to be the unit matrix.
   *>
   *> To apply H**H (the conjugate transpose of H), supply conjg(tau) instead
   *> tau.
   *>
   *> H is a product of k elementary reflectors as returned by ZTZRZF.
   *> \endverbatim
   *
   *  Arguments:
   *  ==========
   *
   *> \param[in] SIDE
   *> \verbatim
   *>          SIDE is CHARACTER*1
   *>          = 'L': form  H * C
   *>          = 'R': form  C * H
   *> \endverbatim
   *>
   *> \param[in] M
   *> \verbatim
   *>          M is INTEGER
   *>          The number of rows of the matrix C.
   *> \endverbatim
   *>
   *> \param[in] N
   *> \verbatim
   *>          N is INTEGER
   *>          The number of columns of the matrix C.
   *> \endverbatim
   *>
   *> \param[in] L
   *> \verbatim
   *>          L is INTEGER
   *>          The number of entries of the vector V containing
   *>          the meaningful part of the Householder vectors.
   *>          If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0.
   *> \endverbatim
   *>
   *> \param[in] V
   *> \verbatim
   *>          V is COMPLEX*16 array, dimension (1+(L-1)*abs(INCV))
   *>          The vector v in the representation of H as returned by
   *>          ZTZRZF. V is not used if TAU = 0.
   *> \endverbatim
   *>
   *> \param[in] INCV
   *> \verbatim
   *>          INCV is INTEGER
   *>          The increment between elements of v. INCV <> 0.
   *> \endverbatim
   *>
   *> \param[in] TAU
   *> \verbatim
   *>          TAU is COMPLEX*16
   *>          The value tau in the representation of H.
   *> \endverbatim
   *>
   *> \param[in,out] C
   *> \verbatim
   *>          C is COMPLEX*16 array, dimension (LDC,N)
   *>          On entry, the M-by-N matrix C.
   *>          On exit, C is overwritten by the matrix H * C if SIDE = 'L',
   *>          or C * H if SIDE = 'R'.
   *> \endverbatim
   *>
   *> \param[in] LDC
   *> \verbatim
   *>          LDC is INTEGER
   *>          The leading dimension of the array C. LDC >= max(1,M).
   *> \endverbatim
   *>
   *> \param[out] WORK
   *> \verbatim
   *>          WORK is COMPLEX*16 array, dimension
   *>                         (N) if SIDE = 'L'
   *>                      or (M) if SIDE = 'R'
   *> \endverbatim
   *
   *  Authors:
   *  ========
   *
   *> \author Univ. of Tennessee
   *> \author Univ. of California Berkeley
   *> \author Univ. of Colorado Denver
   *> \author NAG Ltd.
   *
   *> \date December 2016
   *
   *> \ingroup complex16OTHERcomputational
   *
   *> \par Contributors:
   *  ==================
   *>
   *>    A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA
   *
   *> \par Further Details:
   *  =====================
   *>
   *> \verbatim
   *> \endverbatim
   *>
   *  =====================================================================
       SUBROUTINE ZLARZ( SIDE, M, N, L, V, INCV, TAU, C, LDC, WORK )        SUBROUTINE ZLARZ( SIDE, M, N, L, V, INCV, TAU, C, LDC, WORK )
 *  *
 *  -- LAPACK routine (version 3.2) --  *  -- LAPACK computational routine (version 3.7.0) --
 *  -- 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  *     December 2016
 *  *
 *     .. Scalar Arguments ..  *     .. Scalar Arguments ..
       CHARACTER          SIDE        CHARACTER          SIDE
Line 14 Line 161
       COMPLEX*16         C( LDC, * ), V( * ), WORK( * )        COMPLEX*16         C( LDC, * ), V( * ), WORK( * )
 *     ..  *     ..
 *  *
 *  Purpose  
 *  =======  
 *  
 *  ZLARZ applies a complex elementary reflector H to a complex  
 *  M-by-N matrix C, from either the left or the right. H is represented  
 *  in the form  
 *  
 *        H = I - tau * v * v'  
 *  
 *  where tau is a complex scalar and v is a complex vector.  
 *  
 *  If tau = 0, then H is taken to be the unit matrix.  
 *  
 *  To apply H' (the conjugate transpose of H), supply conjg(tau) instead  
 *  tau.  
 *  
 *  H is a product of k elementary reflectors as returned by ZTZRZF.  
 *  
 *  Arguments  
 *  =========  
 *  
 *  SIDE    (input) CHARACTER*1  
 *          = 'L': form  H * C  
 *          = 'R': form  C * H  
 *  
 *  M       (input) INTEGER  
 *          The number of rows of the matrix C.  
 *  
 *  N       (input) INTEGER  
 *          The number of columns of the matrix C.  
 *  
 *  L       (input) INTEGER  
 *          The number of entries of the vector V containing  
 *          the meaningful part of the Householder vectors.  
 *          If SIDE = 'L', M >= L >= 0, if SIDE = 'R', N >= L >= 0.  
 *  
 *  V       (input) COMPLEX*16 array, dimension (1+(L-1)*abs(INCV))  
 *          The vector v in the representation of H as returned by  
 *          ZTZRZF. V is not used if TAU = 0.  
 *  
 *  INCV    (input) INTEGER  
 *          The increment between elements of v. INCV <> 0.  
 *  
 *  TAU     (input) COMPLEX*16  
 *          The value tau in the representation of H.  
 *  
 *  C       (input/output) COMPLEX*16 array, dimension (LDC,N)  
 *          On entry, the M-by-N matrix C.  
 *          On exit, C is overwritten by the matrix H * C if SIDE = 'L',  
 *          or C * H if SIDE = 'R'.  
 *  
 *  LDC     (input) INTEGER  
 *          The leading dimension of the array C. LDC >= max(1,M).  
 *  
 *  WORK    (workspace) COMPLEX*16 array, dimension  
 *                         (N) if SIDE = 'L'  
 *                      or (M) if SIDE = 'R'  
 *  
 *  Further Details  
 *  ===============  
 *  
 *  Based on contributions by  
 *    A. Petitet, Computer Science Dept., Univ. of Tenn., Knoxville, USA  
 *  
 *  =====================================================================  *  =====================================================================
 *  *
 *     .. Parameters ..  *     .. Parameters ..
Line 105 Line 188
             CALL ZCOPY( N, C, LDC, WORK, 1 )              CALL ZCOPY( N, C, LDC, WORK, 1 )
             CALL ZLACGV( N, WORK, 1 )              CALL ZLACGV( N, WORK, 1 )
 *  *
 *           w( 1:n ) = conjg( w( 1:n ) + C( m-l+1:m, 1:n )' * v( 1:l ) )  *           w( 1:n ) = conjg( w( 1:n ) + C( m-l+1:m, 1:n )**H * v( 1:l ) )
 *  *
             CALL ZGEMV( 'Conjugate transpose', L, N, ONE, C( M-L+1, 1 ),              CALL ZGEMV( 'Conjugate transpose', L, N, ONE, C( M-L+1, 1 ),
      $                  LDC, V, INCV, ONE, WORK, 1 )       $                  LDC, V, INCV, ONE, WORK, 1 )
Line 116 Line 199
             CALL ZAXPY( N, -TAU, WORK, 1, C, LDC )              CALL ZAXPY( N, -TAU, WORK, 1, C, LDC )
 *  *
 *           C( m-l+1:m, 1:n ) = C( m-l+1:m, 1:n ) - ...  *           C( m-l+1:m, 1:n ) = C( m-l+1:m, 1:n ) - ...
 *                               tau * v( 1:l ) * conjg( w( 1:n )' )  *                               tau * v( 1:l ) * w( 1:n )**H
 *  *
             CALL ZGERU( L, N, -TAU, V, INCV, WORK, 1, C( M-L+1, 1 ),              CALL ZGERU( L, N, -TAU, V, INCV, WORK, 1, C( M-L+1, 1 ),
      $                  LDC )       $                  LDC )
Line 142 Line 225
             CALL ZAXPY( M, -TAU, WORK, 1, C, 1 )              CALL ZAXPY( M, -TAU, WORK, 1, C, 1 )
 *  *
 *           C( 1:m, n-l+1:n ) = C( 1:m, n-l+1:n ) - ...  *           C( 1:m, n-l+1:n ) = C( 1:m, n-l+1:n ) - ...
 *                               tau * w( 1:m ) * v( 1:l )'  *                               tau * w( 1:m ) * v( 1:l )**H
 *  *
             CALL ZGERC( M, L, -TAU, WORK, 1, V, INCV, C( 1, N-L+1 ),              CALL ZGERC( M, L, -TAU, WORK, 1, V, INCV, C( 1, N-L+1 ),
      $                  LDC )       $                  LDC )
Removed from v.1.5  
changed lines
  Added in v.1.18

CVSweb interface <joel.bertrand@systella.fr>