MPI_Type_contiguous(3) Open MPI MPI_Type_contiguous(3)NAMEMPI_Type_contiguous - Creates a contiguous datatype.
SYNTAXC Syntax
#include <mpi.h>
int MPI_Type_contiguous(int count, MPI_Datatype oldtype,
MPI_Datatype *newtype)
Fortran Syntax
INCLUDE 'mpif.h'
MPI_TYPE_CONTIGUOUS(COUNT, OLDTYPE, NEWTYPE, IERROR)
INTEGER COUNT, OLDTYPE, NEWTYPE, IERROR
C++ Syntax
#include <mpi.h>
Datatype Datatype::Create_contiguous(int count) const
INPUT PARAMETERS
count Replication count (nonnegative integer).
oldtype Old datatype (handle).
OUTPUT PARAMETERS
newtype New datatype (handle).
IERROR Fortran only: Error status (integer).
DESCRIPTION
The simplest datatype constructor is MPI_Type_contiguous, which allows
replication of a datatype into contiguous locations.
newtype is the datatype obtained by concatenating count copies of old‐
type. Concatenation is defined using the extent of oldtype as the size
of the concatenated copies.
Example: Let oldtype have type map {(double, 0), (char, 8)}, with
extent 16, and let count = 3. The type map of the datatype returned by
newtype is
{(double, 0), (char, 8), (double, 16), (char, 24),
(double, 32), (char, 40)];
i.e., alternating double and char elements, with displacements 0, 8,
16, 24, 32, 40.
In general, assume that the type map of oldtype is
{(type(0), disp(0)),...,(type(n-1), disp(n-1))},
with extent ex. Then newtype has a type map with count times n entries
defined by:
{(type(0), disp(0)), ...,(type(n-1), disp(n-1)),
(type(0), disp(0) + ex), ...,(type(n-1),
disp(n-1) + ex), ...,(type(0), disp(0) + ex * (count - 1)),
...,(type(n-1), disp(n-1) + ex * (count - 1))}.
For more information about derived datatypes, see Section 3.12 of the
MPI-1 Standard.
ERRORS
Almost all MPI routines return an error value; C routines as the value
of the function and Fortran routines in the last argument. C++ func‐
tions do not return errors. If the default error handler is set to
MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism
will be used to throw an MPI::Exception object.
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
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.
1.7.4 Feb 04, 2014 MPI_Type_contiguous(3)
