MPI_Type_create_indexed_block - Create an indexed datatype with constant-sized
int MPI_Type_create_indexed_block(int count,
const int array_of_displacements,
- - length of array of displacements (integer)
- - size of block (integer)
- - array of displacements (array of integer)
- - old datatype (handle)
- - new datatype (handle)
The indices are displacements, and are based on a zero origin. A common error is
to do something like the following
integer blens(10), indices(10)
10 indices(i) = 1 + (i-1)*10
expecting this to send "a(1),a(11),..." because the indices have
values "1,11,...". Because these are displacements
beginning of "a", it actually sends "a(1+1),a(1+11),...".
If you wish to consider the displacements as indices into a Fortran array,
consider declaring the Fortran array with a zero origin
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.
All MPI routines in Fortran (except for MPI_WTIME
have an additional argument ierr
at the end of the argument list.
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
All MPI objects (e.g., MPI_Datatype
) are of type
All MPI routines (except MPI_Wtime
) 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 files), and MPI_Win_set_errhandler
(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
guarentee that an MPI program can continue past an error; however,
MPI implementations will attempt to continue whenever possible.
- - No error; MPI routine completed successfully.
- - Invalid datatype argument. Additionally, this error can occur if an
uncommitted MPI_Datatype (see MPI_Type_commit ) is used in a
- - Invalid argument. Some argument is invalid and is not identified by a
specific error class (e.g., MPI_ERR_RANK ).