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      SUBROUTINE DLASDT( N, LVL, ND, INODE, NDIML, NDIMR, MSUB )
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*
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*  -- LAPACK auxiliary routine (version 3.2.2) --
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*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
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*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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*     June 2010
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*
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*     .. Scalar Arguments ..
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      INTEGER            LVL, MSUB, N, ND
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*     ..
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*     .. Array Arguments ..
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      INTEGER            INODE( * ), NDIML( * ), NDIMR( * )
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*     ..
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*
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*  Purpose
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*  =======
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*
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*  DLASDT creates a tree of subproblems for bidiagonal divide and
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*  conquer.
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*
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*  Arguments
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*  =========
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*
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*   N      (input) INTEGER
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*          On entry, the number of diagonal elements of the
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*          bidiagonal matrix.
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*
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*   LVL    (output) INTEGER
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*          On exit, the number of levels on the computation tree.
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*
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*   ND     (output) INTEGER
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*          On exit, the number of nodes on the tree.
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*
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*   INODE  (output) INTEGER array, dimension ( N )
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*          On exit, centers of subproblems.
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*
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*   NDIML  (output) INTEGER array, dimension ( N )
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*          On exit, row dimensions of left children.
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*
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*   NDIMR  (output) INTEGER array, dimension ( N )
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*          On exit, row dimensions of right children.
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*
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*   MSUB   (input) INTEGER
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*          On entry, the maximum row dimension each subproblem at the
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*          bottom of the tree can be of.
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*
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*  Further Details
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*  ===============
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*
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*  Based on contributions by
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*     Ming Gu and Huan Ren, Computer Science Division, University of
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*     California at Berkeley, USA
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*
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*  =====================================================================
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*
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*     .. Parameters ..
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      DOUBLE PRECISION   TWO
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      PARAMETER          ( TWO = 2.0D+0 )
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*     ..
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*     .. Local Scalars ..
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      INTEGER            I, IL, IR, LLST, MAXN, NCRNT, NLVL
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      DOUBLE PRECISION   TEMP
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*     ..
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*     .. Intrinsic Functions ..
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      INTRINSIC          DBLE, INT, LOG, MAX
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*     ..
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*     .. Executable Statements ..
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*
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*     Find the number of levels on the tree.
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*
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      MAXN = MAX( 1, N )
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      TEMP = LOG( DBLE( MAXN ) / DBLE( MSUB+1 ) ) / LOG( TWO )
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      LVL = INT( TEMP ) + 1
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*
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      I = N / 2
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      INODE( 1 ) = I + 1
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      NDIML( 1 ) = I
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      NDIMR( 1 ) = N - I - 1
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      IL = 0
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      IR = 1
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      LLST = 1
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      DO 20 NLVL = 1, LVL - 1
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*
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*        Constructing the tree at (NLVL+1)-st level. The number of
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*        nodes created on this level is LLST * 2.
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*
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         DO 10 I = 0, LLST - 1
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            IL = IL + 2
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            IR = IR + 2
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            NCRNT = LLST + I
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            NDIML( IL ) = NDIML( NCRNT ) / 2
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            NDIMR( IL ) = NDIML( NCRNT ) - NDIML( IL ) - 1
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            INODE( IL ) = INODE( NCRNT ) - NDIMR( IL ) - 1
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            NDIML( IR ) = NDIMR( NCRNT ) / 2
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            NDIMR( IR ) = NDIMR( NCRNT ) - NDIML( IR ) - 1
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            INODE( IR ) = INODE( NCRNT ) + NDIML( IR ) + 1
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   10    CONTINUE
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         LLST = LLST*2
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   20 CONTINUE
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      ND = LLST*2 - 1
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*
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      RETURN
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*
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*     End of DLASDT
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*
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      END