mpi

Class Datatype

java.lang.Object

mpi.Datatype

public abstract class Datatype
extends java.lang.Object

The Datatype class represents MPI_DATATYPE handles.

Field Summary

Fields

Modifier and Type	Field and Description
int	baseType

Constructor Summary

Constructors

Constructor and Description
Datatype()

Method Summary

Modifier and Type	Method and Description
void	commit() Commit a derived datatype.
static Datatype	createContiguous(int count, Datatype oldtype) Construct new datatype representing replication of old datatype into contiguous locations.
static Datatype	createHVector(int count, int blocklength, int stride, Datatype oldtype) Identical to vector except that the stride is expressed directly in terms of the buffer index, rather than the units of the old type.
static Datatype	createIndexed(int[] array_of_blocklengths, int[] array_of_displacements, Datatype oldtype) Construct new datatype representing replication of old datatype into a sequence of blocks where each block can contain a different number of copies and have a different displacement.
static Datatype	createVector(int count, int blocklength, int stride, Datatype oldtype) Construct new datatype representing replication of old datatype into locations that consist of equally spaced blocks.
int	extent() Returns the extent of a datatype - the difference between upper and lower bound.
void	free() Frees the datatype.
int	getByteSize()
int	getType()
static Datatype	hIndexed(int[] array_of_blocklengths, int[] array_of_displacements, Datatype oldtype) Identical to indexed except that the displacements are expressed directly in terms of the buffer index, rather than the units of the old type.
int	lb() Find the lower bound of a datatype - the least value in its displacement sequence.
int	size() Returns the total size of a datatype - the number of buffer elements it represents.
static Datatype	struct(int[] array_of_blocklengths, int[] array_of_displacements, Datatype[] array_of_types) The most general type constructor.
int	ub() Find the upper bound of a datatype - the greatest value in its displacement sequence.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

baseType

public int baseType

Constructor Detail

Datatype

public Datatype()

Method Detail

createContiguous

public static Datatype createContiguous(int count,
                                        Datatype oldtype)
                                 throws MPIException

Construct new datatype representing replication of old datatype into contiguous locations.

Parameters:

count - replication count.

oldtype - datatype.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_CONTIGUOUS.

The base type of the new datatype is the same as the base type of oldtype.

Throws:

MPIException - Points out that an MPI exception has occured.

createVector

public static Datatype createVector(int count,
                                    int blocklength,
                                    int stride,
                                    Datatype oldtype)
                             throws MPIException

Construct new datatype representing replication of old datatype into locations that consist of equally spaced blocks.

Parameters:

count - number of blocks.

blocklength - number of elements in each block.

stride - number of elements between start of each block.

oldtype - old datatype.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_VECTOR.

The base type of the new datatype is the same as the base type of oldtype.

Throws:

MPIException - Points out that an MPI exception has occured.

createHVector

public static Datatype createHVector(int count,
                                     int blocklength,
                                     int stride,
                                     Datatype oldtype)
                              throws MPIException

Identical to vector except that the stride is expressed directly in terms of the buffer index, rather than the units of the old type.

Parameters:

count - number of blocks.

blocklength - number of elements in each block.

stride - number of elements between start of each block.

oldtype - old datatype.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_CREATE_HVECTOR.

Unlike other language bindings, the value of stride is not measured in bytes.

Throws:

MPIException - Points out that an MPI exception has occured.

createIndexed

public static Datatype createIndexed(int[] array_of_blocklengths,
                                     int[] array_of_displacements,
                                     Datatype oldtype)
                              throws MPIException

Construct new datatype representing replication of old datatype into a sequence of blocks where each block can contain a different number of copies and have a different displacement.

Parameters:

array_of_blocklengths - number of elements per block.

array_of_displacements - displacement of each block in units of old type.

oldtype - old datatype.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_INDEXED.

The number of blocks is taken to be size of the array_of_blocklengths argument. The second argument, array_of_displacements, should be the same size. The base type of the new datatype is the same as the base type of oldtype.

Throws:

MPIException - Points out that an MPI exception has occured.

hIndexed

public static Datatype hIndexed(int[] array_of_blocklengths,
                                int[] array_of_displacements,
                                Datatype oldtype)
                         throws MPIException

Identical to indexed except that the displacements are expressed directly in terms of the buffer index, rather than the units of the old type.

Parameters:

array_of_blocklengths - number of elements per block.

array_of_displacements - displacement in buffer for each block.

oldtype - old datatype.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_HINDEXED.

Unlike other language bindings, the values in array_of_displacements are not measured in bytes.

Throws:

MPIException - Points out that an MPI exception has occured.

struct

public static Datatype struct(int[] array_of_blocklengths,
                              int[] array_of_displacements,
                              Datatype[] array_of_types)
                       throws MPIException

The most general type constructor.

Parameters:

array_of_blocklengths - number of elements per block.

array_of_displacements - displacement in buffer for each block.

array_of_types - type of elements in each block.

Returns:

new datatype.

Java binding of the MPI operation MPI_TYPE_STRUCT.

The number of blocks is taken to be size of the array_of_blocklengths argument. The second and third arguments, array_of_displacements, and array_of_types, should be the same size. Unlike other language bindings, the values in array_of_displacements are not measured in bytes. All elements of array_of_types with definite base types must have the same base type: this will be the base type of new datatype.

Throws:

MPIException - Points out that an MPI exception has occured.

getType

public int getType()

getByteSize

public int getByteSize()

extent

public int extent()
           throws MPIException

Returns the extent of a datatype - the difference between upper and lower bound.

Returns:

datatype extent.

Java binding of the MPI operation MPI_TYPE_EXTENT.

Throws:

MPIException - Points out that an MPI exception has occured.

size

public int size()
         throws MPIException

Returns the total size of a datatype - the number of buffer elements it represents.

Returns:

datatype size.

Java binding of the MPI operation MPI_TYPE_SIZE.

Throws:

MPIException - Points out that an MPI exception has occured.

lb

public int lb()
       throws MPIException

Find the lower bound of a datatype - the least value in its displacement sequence.

Returns:

displacement of lower bound from origin.

Java binding of the MPI operation MPI_TYPE_LB.

Throws:

MPIException - Points out that an MPI exception has occured.

ub

public int ub()
       throws MPIException

Find the upper bound of a datatype - the greatest value in its displacement sequence.

Returns:

displacement of upper bound from origin.

Java binding of the MPI operation MPI_TYPE_UB.

Throws:

MPIException - Points out that an MPI exception has occured.

commit

public void commit()
            throws MPIException

Commit a derived datatype.

Java binding of the MPI operation MPI_TYPE_COMMIT.

Throws:

MPIException - Points out that an MPI exception has occured.

free

public void free()
          throws MPIException

Frees the datatype.

Java binding of the MPI operation MPI_TYPE_FREE.

Not Implemented in the current release

.

Throws:

MPIException - Points out that an MPI exception has occured.