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       PDLARED2D  -  redistribute a 1D array  It assumes that the input array,
       BYROW, is distributed across columns and that all process rows  contain
       the same copy of BYROW



           INTEGER           IA, JA, LWORK, N

           INTEGER           DESC( * )

           DOUBLE            PRECISION BYALL( * ), BYROW( * ), WORK( LWORK )


       PDLARED2D redistributes a 1D array and will contain the entire array.


       Each  global  data  object  is  described  by an associated description
       vector.  This vector stores the information required to  establish  the
       mapping  between  an  object  element and its corresponding process and
       memory location.

       Let A be a generic term for any 2D block  cyclicly  distributed  array.
       Such a global array has an associated description vector DESCA.  In the
       following comments, the character _ should be read as  "of  the  global

       ---------------  --------------  --------------------------------------
       DTYPE_A(global) DESCA( DTYPE_ )The descriptor type.  In this case,
                                      DTYPE_A = 1.
       CTXT_A (global) DESCA( CTXT_ ) The BLACS context handle, indicating
                                      the BLACS process grid A is distribu-
                                      ted over. The context itself is glo-
                                      bal, but the handle (the integer
                                      value) may vary.
       M_A    (global) DESCA( M_ )    The number of rows in the global
                                      array A.
       N_A    (global) DESCA( N_ )    The number of columns in the global
                                      array A.
       MB_A   (global) DESCA( MB_ )   The blocking factor used to distribute
                                      the rows of the array.
       NB_A   (global) DESCA( NB_ )   The blocking factor used to distribute
                                      the columns of the array.
       RSRC_A (global) DESCA( RSRC_ ) The process row over which the first
                                      row  of  the  array  A  is  distributed.
       CSRC_A (global) DESCA( CSRC_ ) The process column over which the
                                      first column of the array A is
       LLD_A  (local)  DESCA( LLD_ )  The leading dimension of the local
                                      array.  LLD_A >= MAX(1,LOCr(M_A)).

       Let  K  be  the  number of rows or columns of a distributed matrix, and
       assume that its process grid has dimension p x q.
       LOCr( K ) denotes the number of elements of  K  that  a  process  would
       receive  if  K  were  distributed  over  the p processes of its process
       Similarly, LOCc( K ) denotes the number of elements of K that a process
       would receive if K were distributed over the q processes of its process
       The values of LOCr() and LOCc() may be determined via  a  call  to  the
       ScaLAPACK tool function, NUMROC:
               LOCr( M ) = NUMROC( M, MB_A, MYROW, RSRC_A, NPROW ),
               LOCc(  N ) = NUMROC( N, NB_A, MYCOL, CSRC_A, NPCOL ).  An upper
       bound for these quantities may be computed by:
               LOCr( M ) <= ceil( ceil(M/MB_A)/NPROW )*MB_A
               LOCc( N ) <= ceil( ceil(N/NB_A)/NPCOL )*NB_A


       NP = Number of local rows in BYROW()

       N       (global input) INTEGER
               The number of elements to be redistributed.  N >= 0.

       IA      (global input) INTEGER
               IA must be equal to 1

       JA      (global input) INTEGER
               JA must be equal to 1

       DESC    (global/local input) INTEGER Array of dimension DLEN_
               A 2D array descriptor, which describes BYROW

       BYROW   (local input) distributed block cyclic DOUBLE PRECISION array
               global dimension (N), local dimension NP BYCOL  is  distributed
               across  the  process  columns  All  process rows are assumed to
               contain the same value

       BYALL   (global output) DOUBLE PRECISION global dimension( N )
               local  dimension  (N)  BYALL  is  exactly  duplicated  on   all
               processes  It  contains  the  same  values  as BYCOL, but it is
               replicated across all processes rather than being distributed

               BYALL(i) = BYCOL(  NUMROC(i,NB,MYROW,0,NPROW  )  on  the  procs
               whose MYROW == mod((i-1)/NB,NPROW)

       WORK    (local workspace) DOUBLE PRECISION dimension (LWORK)
               Used to hold the buffers sent from one process to another

       LWORK   (local input) INTEGER size of WORK array LWORK >=
               LWORK >= NUMROC(N, DESC( NB_ ), 0, 0, NPCOL)