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MPI_Type_create_indexed_block(3)      MPI     MPI_Type_create_indexed_block(3)

NAME
       MPI_Type_create_indexed_block  -	  Create an indexed datatype with con-
       stant-sized blocks

SYNOPSIS
       int MPI_Type_create_indexed_block(int count,
				      int blocklength,
				      MPICH2_CONST int array_of_displacements[],
				      MPI_Datatype oldtype,
				      MPI_Datatype *newtype)

INPUT PARAMETERS
       count  -	length of array	of displacements (integer)
       blocklength
	      -	size of	block (integer)
       array_of_displacements
	      -	array of displacements (array of integer)
       oldtype
	      -	old datatype (handle)

OUTPUT PARAMETER
       newtype
	      -	new datatype (handle)

NOTES
       The indices are displacements, and are based on a zero origin.  A  com-
       mon error is to do something like the following
       integer a(100)
       integer blens(10), indices(10)
       do i=1,10
       10	indices(i) = 1 + (i-1)*10
       call MPI_TYPE_CREATE_INDEXED_BLOCK(10,1,indices,MPI_INTEGER,newtype,ierr)
       call MPI_TYPE_COMMIT(newtype,ierr)
       call MPI_SEND(a,1,newtype,...)

       expecting  this to send a(1),a(11),...  because the indices have	values
       1,11,...	 .  Because these are displacements from the beginning of a  ,
       it actually sends a(1+1),a(1+11),...  .

       If you wish to consider the displacements as indices into a Fortran ar-
       ray, consider declaring the Fortran array with a	zero origin
       integer a(0:99)

THREAD AND INTERRUPT SAFETY
       This routine is thread-safe.  This  means  that	this  routine  may  be
       safely  used by multiple	threads	without	the need for any user-provided
       thread locks.  However, the routine is not interrupt safe.   Typically,
       this  is	due to the use of memory allocation routines such as malloc or
       other non-MPICH runtime routines	that  are  themselves  not  interrupt-
       safe.

NOTES FOR FORTRAN
       All  MPI	routines in Fortran (except for	MPI_WTIME and MPI_WTICK	) have
       an additional argument ierr at the end of the argument list.   ierr  is
       an  integer and has the same meaning as the return value	of the routine
       in C.  In Fortran, MPI routines are subroutines,	and are	 invoked  with
       the call	statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm )	are of type INTEGER in
       Fortran.

ERRORS
       All MPI routines	(except	MPI_Wtime and  MPI_Wtick  )  return  an	 error
       value;  C routines as the value of the function and Fortran routines in
       the last	argument.  Before the value is returned, the current MPI error
       handler	is called.  By default,	this error handler aborts the MPI job.
       The error handler may be	changed	with MPI_Comm_set_errhandler (for com-
       municators),  MPI_File_set_errhandler  (for files), and MPI_Win_set_er-
       rhandler	(for RMA windows).  The	MPI-1 routine  MPI_Errhandler_set  may
       be  used	 but  its  use	is  deprecated.	  The predefined error handler
       MPI_ERRORS_RETURN may be	used to	cause error  values  to	 be  returned.
       Note  that MPI does not guarentee that an MPI program can continue past
       an error; however, MPI implementations will attempt to  continue	 when-
       ever possible.

       MPI_SUCCESS
	      -	No error; MPI routine completed	successfully.
       MPI_ERR_TYPE
	      -	Invalid	datatype argument.  May	be an uncommitted MPI_Datatype
	      (see MPI_Type_commit ).
       MPI_ERR_ARG
	      -	Invalid	argument.  Some	argument is invalid and	is not identi-
	      fied by a	specific error class (e.g., MPI_ERR_RANK ).

LOCATION
       src/mpi/datatype/type_create_indexed_block.c

				   9/20/2012  MPI_Type_create_indexed_block(3)

NAME | SYNOPSIS | INPUT PARAMETERS | OUTPUT PARAMETER | NOTES | THREAD AND INTERRUPT SAFETY | NOTES FOR FORTRAN | ERRORS | LOCATION

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