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PZLACGV(l)			       )			    PZLACGV(l)

NAME
       PZLACGV	- conjugate a complex vector of	length N, sub( X ), where sub(
       X ) denotes X(IX,JX:JX+N-1) if INCX = DESCX( M_ )  and  X(IX:IX+N-1,JX)
       if  INCX	= 1, and  Notes	=====  Each global data	object is described by
       an associated description vector

SYNOPSIS
       SUBROUTINE PZLACGV( N, X, IX, JX, DESCX,	INCX )

	   INTEGER	   INCX, IX, JX, N

	   INTEGER	   DESCX( * )

	   COMPLEX*16	   X( *	)

PURPOSE
       PZLACGV conjugates a complex vector of length N,	sub( X ), where	sub( X
       )  denotes X(IX,JX:JX+N-1) if INCX = DESCX( M_ )	and X(IX:IX+N-1,JX) if
       INCX = 1, and Notes ===== Each global data object is  described	by  an
       associated  description	vector.	This vector stores the information re-
       quired to establish the mapping between an object element and its  cor-
       responding 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
       array".

       NOTATION	       STORED IN      EXPLANATION
       ---------------	--------------	--------------------------------------
       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
				      distributed.
       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 as-
       sume that its process grid has dimension	p x q.
       LOCr(  K	) denotes the number of	elements of K that a process would re-
       ceive if	K were distributed over	the p processes	of its process column.
       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
       row.
       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

       Because vectors may be viewed as	a subclass of matrices,	a  distributed
       vector is considered to be a distributed	matrix.

ARGUMENTS
       N       (global input) INTEGER
	       The length of the distributed vector sub( X ).

       X       (local input/local output) COMPLEX*16 pointer into the
	       local  memory to	an array of dimension (LLD_X,*).  On entry the
	       vector to be conjugated x( i )  =  X(IX+(JX-1)*M_X  +(i-1)*INCX
	       ), 1 <= i <= N.	On exit	the conjugated vector.

       IX      (global input) INTEGER
	       The row index in	the global array X indicating the first	row of
	       sub( X ).

       JX      (global input) INTEGER
	       The column index	in the global array  X	indicating  the	 first
	       column of sub( X	).

       DESCX   (global and local input)	INTEGER	array of dimension DLEN_.
	       The array descriptor for	the distributed	matrix X.

       INCX    (global input) INTEGER
	       The  global increment for the elements of X. Only two values of
	       INCX are	supported in this version, namely  1  and  M_X.	  INCX
	       must not	be zero.

ScaLAPACK version 1.7		13 August 2001			    PZLACGV(l)

NAME | SYNOPSIS | PURPOSE | ARGUMENTS

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