NAME¶
MPI_Type_hindexed - Creates an indexed datatype with offsets in bytes
SYNOPSIS¶
int MPI_Type_hindexed(int count,
const int *array_of_blocklengths,
const MPI_Aint *array_of_displacements,
MPI_Datatype oldtype,
MPI_Datatype *newtype)
- count
- - number of blocks -- also number of entries in array_of_displacements and
array_of_blocklengths
- array_of_blocklengths
- - number of elements in each block (array of nonnegative integers)
- array_of_displacements
- - byte displacement of each block (array of MPI_Aint)
- oldtype
- - old datatype (handle)
OUTPUT PARAMETERS¶
- newtype
- - new datatype (handle)
DEPRECATED FUNCTION¶
The MPI-2 standard deprecated a number of routines because MPI-2 provides better
versions. This routine is one of those that was deprecated. The routine may
continue to be used, but new code should use the replacement routine. This
routine is replaced by
MPI_Type_create_hindexed .
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.
The array_of_displacements are displacements, and are based on a zero origin. A
common error is to do something like to following
integer a(100)
integer array_of_blocklengths(10), array_of_displacements(10)
do i=1,10
array_of_blocklengths(i) = 1
10 array_of_displacements(i) = (1 + (i-1)*10) * sizeofint
call MPI_TYPE_HINDEXED(10,array_of_blocklengths,array_of_displacements,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
array_of_displacements 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 array_of_displacements into a
Fortran array, consider declaring the Fortran array with a zero origin
integer a(0:99)
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 communicators),
MPI_File_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
not guarentee that an MPI program can continue past an error; however,
MPI implementations will attempt to continue whenever 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_COUNT
- - Invalid count argument. Count arguments must be non-negative; a count of
zero is often valid.
- MPI_ERR_INTERN
- - This error is returned when some part of the MPICH implementation is
unable to acquire memory.
- MPI_ERR_ARG
- - Invalid argument. Some argument is invalid and is not identified by a
specific error class (e.g., MPI_ERR_RANK ).
LOCATION¶
/tmp/gyCYfBi4J6/mpich-3.1/src/mpi/datatype/type_hindexed.c