.. _mpi_type_create_indexed_block:


MPI_Type_create_indexed_block
=============================

.. include_body

:ref:`MPI_Type_create_indexed_block`, :ref:`MPI_Type_create_hindexed_block` -
Creates an indexed data type with the same block length for all blocks.


SYNTAX
------


C Syntax
^^^^^^^^

.. code-block:: c

   #include <mpi.h>

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

   int MPI_Type_create_hindexed_block(int count, int blocklength, const MPI_Aint array_of_displacements[], MPI_Datatype oldtype, MPI_Datatype *newtype)


Fortran Syntax
^^^^^^^^^^^^^^

.. code-block:: fortran

   USE MPI
   ! or the older form: INCLUDE 'mpif.h'
   MPI_TYPE_CREATE_INDEXED_BLOCK(COUNT, BLOCKLENGTH,
   		ARRAY_OF_DISPLACEMENTS, OLDTYPE, NEWTYPE, IERROR)
   	INTEGER	COUNT, BLOCKLENGTH, ARRAY_OF_DISPLACEMENTS(*),
   	        OLDTYPE, NEWTYPE, IERROR

   MPI_TYPE_CREATE_HINDEXED_BLOCK(COUNT, BLOCKLENGTH,
   		ARRAY_OF_DISPLACEMENTS, OLDTYPE, NEWTYPE, IERROR)
   	INTEGER	COUNT, BLOCKLENGTH, OLDTYPE, NEWTYPE
   	INTEGER(KIND=MPI_ADDRESS_KIND) ARRAY_OF_DISPLACEMENTS(*)
   	INTEGER	IERROR


Fortran 2008 Syntax
^^^^^^^^^^^^^^^^^^^

.. code-block:: fortran

   USE mpi_f08
   MPI_Type_create_indexed_block(count, blocklength, array_of_displacements,
   		oldtype, newtype, ierror)
   	INTEGER, INTENT(IN) :: count, blocklength,
   	array_of_displacements(count)
   	TYPE(MPI_Datatype), INTENT(IN) :: oldtype
   	TYPE(MPI_Datatype), INTENT(OUT) :: newtype
   	INTEGER, OPTIONAL, INTENT(OUT) :: ierror

   MPI_Type_create_hindexed_block(count, blocklength, array_of_displacements,
   		oldtype, newtype, ierror)
   	INTEGER, INTENT(IN) :: count, blocklength
   	INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) ::
   	array_of_displacements(count)
   	TYPE(MPI_Datatype), INTENT(IN) :: oldtype
   	TYPE(MPI_Datatype), INTENT(OUT) :: newtype
   	INTEGER, OPTIONAL, INTENT(OUT) :: ierror


INPUT PARAMETERS
----------------
* ``count``: Length of array of displacements (integer).
* ``blocklength``: Size of block (integer).
* ``array_of_displacements``: Array of displacements (array of integers). In units of the extent of *oldtype* for MPI_Type_create_indexed_block and bytes for MPI_Type_create_hindexed_block.
* ``oldtype``: Old data type (handle).

OUTPUT PARAMETERS
-----------------
* ``newtype``: New data type (handle).
* ``IERROR``: Fortran only: Error status (integer).

DESCRIPTION
-----------

:ref:`MPI_Type_create_indexed_block` and :ref:`MPI_Type_create_hindexed_block` create
an indexed data type with the same block length for all blocks. The only
difference between the two functions is :ref:`MPI_Type_create_indexed_block`
takes an array of displacements in units of the extent of *oldtype*
while :ref:`MPI_Type_create_hindexed_block` takes displacements in bytes.


ERRORS
------

Almost all MPI routines return an error value; C routines as the value
of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for
I/O function errors. The error handler may be changed with
:ref:`MPI_Comm_set_errhandler`; the predefined error handler MPI_ERRORS_RETURN
may be used to cause error values to be returned. Note that MPI does not
guarantee that an MPI program can continue past an error.


.. seealso::
   :ref:`MPI_Type_indexed`
