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Mise à jour de Lapack vers la version 3.4.2 et des scripts de compilation
pour rplcas. En particulier, le Makefile.am de giac a été modifié pour ne
compiler que le répertoire src.

    1: *> \brief \b DLASDT creates a tree of subproblems for bidiagonal divide and conquer. Used by sbdsdc.
    2: *
    3: *  =========== DOCUMENTATION ===========
    4: *
    5: * Online html documentation available at 
    6: *            http://www.netlib.org/lapack/explore-html/ 
    7: *
    8: *> \htmlonly
    9: *> Download DLASDT + dependencies 
   10: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dlasdt.f"> 
   11: *> [TGZ]</a> 
   12: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dlasdt.f"> 
   13: *> [ZIP]</a> 
   14: *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dlasdt.f"> 
   15: *> [TXT]</a>
   16: *> \endhtmlonly 
   17: *
   18: *  Definition:
   19: *  ===========
   20: *
   21: *       SUBROUTINE DLASDT( N, LVL, ND, INODE, NDIML, NDIMR, MSUB )
   22: * 
   23: *       .. Scalar Arguments ..
   24: *       INTEGER            LVL, MSUB, N, ND
   25: *       ..
   26: *       .. Array Arguments ..
   27: *       INTEGER            INODE( * ), NDIML( * ), NDIMR( * )
   28: *       ..
   29: *  
   30: *
   31: *> \par Purpose:
   32: *  =============
   33: *>
   34: *> \verbatim
   35: *>
   36: *> DLASDT creates a tree of subproblems for bidiagonal divide and
   37: *> conquer.
   38: *> \endverbatim
   39: *
   40: *  Arguments:
   41: *  ==========
   42: *
   43: *> \param[in] N
   44: *> \verbatim
   45: *>          N is INTEGER
   46: *>          On entry, the number of diagonal elements of the
   47: *>          bidiagonal matrix.
   48: *> \endverbatim
   49: *>
   50: *> \param[out] LVL
   51: *> \verbatim
   52: *>          LVL is INTEGER
   53: *>          On exit, the number of levels on the computation tree.
   54: *> \endverbatim
   55: *>
   56: *> \param[out] ND
   57: *> \verbatim
   58: *>          ND is INTEGER
   59: *>          On exit, the number of nodes on the tree.
   60: *> \endverbatim
   61: *>
   62: *> \param[out] INODE
   63: *> \verbatim
   64: *>          INODE is INTEGER array, dimension ( N )
   65: *>          On exit, centers of subproblems.
   66: *> \endverbatim
   67: *>
   68: *> \param[out] NDIML
   69: *> \verbatim
   70: *>          NDIML is INTEGER array, dimension ( N )
   71: *>          On exit, row dimensions of left children.
   72: *> \endverbatim
   73: *>
   74: *> \param[out] NDIMR
   75: *> \verbatim
   76: *>          NDIMR is INTEGER array, dimension ( N )
   77: *>          On exit, row dimensions of right children.
   78: *> \endverbatim
   79: *>
   80: *> \param[in] MSUB
   81: *> \verbatim
   82: *>          MSUB is INTEGER
   83: *>          On entry, the maximum row dimension each subproblem at the
   84: *>          bottom of the tree can be of.
   85: *> \endverbatim
   86: *
   87: *  Authors:
   88: *  ========
   89: *
   90: *> \author Univ. of Tennessee 
   91: *> \author Univ. of California Berkeley 
   92: *> \author Univ. of Colorado Denver 
   93: *> \author NAG Ltd. 
   94: *
   95: *> \date September 2012
   96: *
   97: *> \ingroup auxOTHERauxiliary
   98: *
   99: *> \par Contributors:
  100: *  ==================
  101: *>
  102: *>     Ming Gu and Huan Ren, Computer Science Division, University of
  103: *>     California at Berkeley, USA
  104: *>
  105: *  =====================================================================
  106:       SUBROUTINE DLASDT( N, LVL, ND, INODE, NDIML, NDIMR, MSUB )
  107: *
  108: *  -- LAPACK auxiliary routine (version 3.4.2) --
  109: *  -- LAPACK is a software package provided by Univ. of Tennessee,    --
  110: *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
  111: *     September 2012
  112: *
  113: *     .. Scalar Arguments ..
  114:       INTEGER            LVL, MSUB, N, ND
  115: *     ..
  116: *     .. Array Arguments ..
  117:       INTEGER            INODE( * ), NDIML( * ), NDIMR( * )
  118: *     ..
  119: *
  120: *  =====================================================================
  121: *
  122: *     .. Parameters ..
  123:       DOUBLE PRECISION   TWO
  124:       PARAMETER          ( TWO = 2.0D+0 )
  125: *     ..
  126: *     .. Local Scalars ..
  127:       INTEGER            I, IL, IR, LLST, MAXN, NCRNT, NLVL
  128:       DOUBLE PRECISION   TEMP
  129: *     ..
  130: *     .. Intrinsic Functions ..
  131:       INTRINSIC          DBLE, INT, LOG, MAX
  132: *     ..
  133: *     .. Executable Statements ..
  134: *
  135: *     Find the number of levels on the tree.
  136: *
  137:       MAXN = MAX( 1, N )
  138:       TEMP = LOG( DBLE( MAXN ) / DBLE( MSUB+1 ) ) / LOG( TWO )
  139:       LVL = INT( TEMP ) + 1
  140: *
  141:       I = N / 2
  142:       INODE( 1 ) = I + 1
  143:       NDIML( 1 ) = I
  144:       NDIMR( 1 ) = N - I - 1
  145:       IL = 0
  146:       IR = 1
  147:       LLST = 1
  148:       DO 20 NLVL = 1, LVL - 1
  149: *
  150: *        Constructing the tree at (NLVL+1)-st level. The number of
  151: *        nodes created on this level is LLST * 2.
  152: *
  153:          DO 10 I = 0, LLST - 1
  154:             IL = IL + 2
  155:             IR = IR + 2
  156:             NCRNT = LLST + I
  157:             NDIML( IL ) = NDIML( NCRNT ) / 2
  158:             NDIMR( IL ) = NDIML( NCRNT ) - NDIML( IL ) - 1
  159:             INODE( IL ) = INODE( NCRNT ) - NDIMR( IL ) - 1
  160:             NDIML( IR ) = NDIMR( NCRNT ) / 2
  161:             NDIMR( IR ) = NDIMR( NCRNT ) - NDIML( IR ) - 1
  162:             INODE( IR ) = INODE( NCRNT ) + NDIML( IR ) + 1
  163:    10    CONTINUE
  164:          LLST = LLST*2
  165:    20 CONTINUE
  166:       ND = LLST*2 - 1
  167: *
  168:       RETURN
  169: *
  170: *     End of DLASDT
  171: *
  172:       END