Manpages - MPI_Type_hvector.3

Table of Contents

NAME

MPI_Type_hvector - Creates a vector (strided) datatype with offset in bytes – use of this routine is deprecated.

SYNTAX

C Syntax

  #include <mpi.h>
  int MPI_Type_hvector(int count, int blocklength, MPI_Aint stride,
  	MPI_Datatype oldtype, MPI_Datatype *newtype)

Fortran Syntax

  INCLUDE 'mpif.h'
  MPI_TYPE_HVECTOR(COUNT, BLOCKLENGTH, STRIDE, OLDTYPE, NEWTYPE,
  		IERROR)
  	INTEGER	COUNT, BLOCKLENGTH, STRIDE, OLDTYPE
  	INTEGER	NEWTYPE, IERROR

INPUT PARAMETERS

count
Number of blocks (nonnegative integer).
blocklength
Number of elements in each block (nonnegative integer).
stride
Number of bytes between start of each block (integer).
oldtype
Old datatype (handle).

OUTPUT PARAMETERS

newtype
New datatype (handle).
IERROR
Fortran only: Error status (integer).

DESCRIPTION

Note that use of this routine is deprecated as of MPI-2. Use MPI_Type_create_hvector instead.

This deprecated routine is not available in C++.

The function MPI_Type_hvector is identical to MPI_Type_vector, except that stride is given in bytes, rather than in elements. The use for both types of vector constructors is illustrated in the examples in Section 3.12.7 of the MPI-1 Standard.

Assume that oldtype has type map

      {(type(0), disp(0)), ..., (type(n-1), disp(n-1))}

with extent ex. Let bl be the blocklength. The newly created datatype has a type map with count * bl * n entries:

    {(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) + (bl -1) * ex),...,(type(n-1),
    disp(n-1) + (bl -1) * ex), (type(0), disp(0) + stride),
    ...,(type(n-1), disp(n-1) + stride), ..., (type(0),
    disp(0) + stride + (bl - 1) * ex), ..., (type(n-1),
    disp(n-1) + stride + (bl -1) * ex), ..., (type(0),
    disp(0) + stride * (count -1)), ...,(type(n-1),
    disp(n-1) + stride * (count -1)), ..., (type(0),
    disp(0) + stride * (count -1) + (bl -1) * ex), ...,
    (type(n-1), disp(n-1) + stride * (count -1) + (bl -1) * ex)}

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++ functions 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.

SEE ALSO

MPI_Type_create_hvector
MPI_Type_vector

Author: dt

Created: 2022-02-20 Sun 17:21