ds.granules.util

Class MatrixColumnMajor

java.lang.Object

ds.granules.util.Matrix

ds.granules.util.MatrixColumnMajor

public class MatrixColumnMajor
extends Matrix

A matrix encapsulator where the Matrix is stored in column-major format for faster reads from the underlying file system.

Author:

Shrideep Pallickara

Field Summary

Fields inherited from class ds.granules.util.Matrix

INT_ENTRIES, LONG_ENTRIES

Constructor Summary

Constructors

Constructor and Description
MatrixColumnMajor(String filename)
MatrixColumnMajor(String filename, int numberOfRows, int numberOfColumns, boolean rowFormat, int entriesType)

Method Summary

Methods

Modifier and Type	Method and Description
static void	main(String[] args)
int[][]	readIntMatrix() Read a matrix that has been written to a file (specified in the constructor) based on the specified rows and columns.
int[]	readIntMatrixColumn(int columnId) This method reads a specified column from the matrix that has been written to a file.
int	readIntMatrixElement(int rowId, int columnId) Reads a matrix element from the underlying file based on the specified [rowId, columId].
int[]	readIntMatrixRow(int rowId) This method reads the specified row of a matrix that has been written to a file.
long[][]	readLongMatrix() Read a matrix that has been written to a file (specified in the constructor) based on the specified rows and columns.
long[]	readLongMatrixColumn(int columnId) This method reads a specified column from the matrix that has been written to a file.
long	readLongMatrixElement(int rowId, int columnId) Reads a matrix element from the underlying file based on the specified [rowId, columId].
long[]	readLongMatrixRow(int rowId) This method reads the specified row of a matrix that has been written to a file.
void	writeIntMatrixColumn(int columnId, int[] columnValues) Write a column of the matrix to the underlying file.
void	writeIntMatrixElement(int rowId, int columnId, int value) Write a specific matrix element code>[rowId, columnId] to the file.
void	writeIntMatrixRow(int rowId, int[] rowValues) Write a row of the matrix to the underlying file.
void	writeLongMatrixColumn(int columnId, long[] columnValues) Write a column of the matrix to the underlying file.
void	writeLongMatrixElement(int rowId, int columnId, long value) Write a specific matrix element code>[rowId, columnId] to the file.
void	writeLongMatrixRow(int rowId, long[] rowValues) Write a row of the matrix to the underlying file.

Methods inherited from class ds.granules.util.Matrix

createDenseIntColumn, createDenseIntRow, getEntriesType, getMetadataLength, getNumberOfColumns, getNumberOfRows, isColumnMajorFormat, isRowMajorFormat, size

Methods inherited from class java.lang.Object

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

Constructor Detail

MatrixColumnMajor

public MatrixColumnMajor(String filename,
                 int numberOfRows,
                 int numberOfColumns,
                 boolean rowFormat,
                 int entriesType)
                  throws IOException

Throws:

IOException

MatrixColumnMajor

public MatrixColumnMajor(String filename)
                  throws IOException

Throws:

IOException

Method Detail

readIntMatrix

public int[][] readIntMatrix()
                      throws IOException

Description copied from class: Matrix

Read a matrix that has been written to a file (specified in the constructor) based on the specified rows and columns. Depending on the size of the matrix, trying to read the entire matrix can lead to OutOfMemoryError

Overrides:

readIntMatrix in class Matrix

Returns:

The matrix[][]

Throws:

IOException - If there are problems reading from the file.

readIntMatrixColumn

public int[] readIntMatrixColumn(int columnId)
                          throws IOException

Description copied from class: Matrix

This method reads a specified column from the matrix that has been written to a file. This method also requires the number of matrix rows to be specified.

Overrides:

readIntMatrixColumn in class Matrix

Parameters:

columnId - The matrix column that needs to be retrieved

Returns:

The column[] in question

Throws:

IOException - If there are problems locating the file or reading its contents.

readIntMatrixElement

public int readIntMatrixElement(int rowId,
                       int columnId)
                         throws IOException

Description copied from class: Matrix

Reads a matrix element from the underlying file based on the specified [rowId, columId].

Overrides:

readIntMatrixElement in class Matrix

Parameters:

rowId - The rowId for the matrix element

columnId - The columnId for the matrix element

Returns:

the value of the matrix[rowId, columnId] element.

Throws:

IOException - If there are problems reading the file.

readIntMatrixRow

public int[] readIntMatrixRow(int rowId)
                       throws IOException

Description copied from class: Matrix

This method reads the specified row of a matrix that has been written to a file. This method also requires the number of columns to be specified.

Overrides:

readIntMatrixRow in class Matrix

Parameters:

rowId - The matrix row that needs to be retrieved

Throws:

IOException - If there are problems locating the file or reading its contents.

readLongMatrix

public long[][] readLongMatrix()
                        throws IOException

Description copied from class: Matrix

Read a matrix that has been written to a file (specified in the constructor) based on the specified rows and columns. Depending on the size of the matrix, trying to read the entire matrix can lead to OutOfMemoryError

Overrides:

readLongMatrix in class Matrix

Returns:

The long[][] matrix

Throws:

IOException - If there are problems reading from the file.

readLongMatrixColumn

public long[] readLongMatrixColumn(int columnId)
                            throws IOException

Description copied from class: Matrix

This method reads a specified column from the matrix that has been written to a file. This method also requires the number of matrix rows to be specified.

Overrides:

readLongMatrixColumn in class Matrix

Parameters:

columnId - The matrix column that needs to be retrieved

Returns:

The column[] in question

Throws:

IOException - If there are problems locating the file or reading its contents.

readLongMatrixElement

public long readLongMatrixElement(int rowId,
                         int columnId)
                           throws IOException

Description copied from class: Matrix

Reads a matrix element from the underlying file based on the specified [rowId, columId].

Overrides:

readLongMatrixElement in class Matrix

Parameters:

rowId - The rowId for the matrix element

columnId - The columnId for the matrix element

Returns:

the value of the matrix[rowId, columnId] element.

Throws:

IOException - If there are problems reading the file.

readLongMatrixRow

public long[] readLongMatrixRow(int rowId)
                         throws IOException

Description copied from class: Matrix

This method reads the specified row of a matrix that has been written to a file. This method also requires the number of columns to be specified.

Overrides:

readLongMatrixRow in class Matrix

Parameters:

rowId - The matrix row that needs to be retrieved

Throws:

IOException - If there are problems locating the file or reading its contents.

writeIntMatrixColumn

public void writeIntMatrixColumn(int columnId,
                        int[] columnValues)
                          throws IOException

Description copied from class: Matrix

Write a column of the matrix to the underlying file.

Overrides:

writeIntMatrixColumn in class Matrix

Parameters:

columnId - The columnId for the matrix column

columnValues - Values associated with the column

Throws:

IOException - If there are problems writing to the file.

writeIntMatrixElement

public void writeIntMatrixElement(int rowId,
                         int columnId,
                         int value)
                           throws IOException

Description copied from class: Matrix

Write a specific matrix element code>[rowId, columnId] to the file.

Overrides:

writeIntMatrixElement in class Matrix

Parameters:

rowId - The row identifier for the element

columnId - The column identifier for the element

value - The value of the matrix element [rowId, columnId]

Throws:

IOException - If there are problems writing to the file.

writeIntMatrixRow

public void writeIntMatrixRow(int rowId,
                     int[] rowValues)
                       throws IOException

Description copied from class: Matrix

Write a row of the matrix to the underlying file.

Overrides:

writeIntMatrixRow in class Matrix

Parameters:

rowId - The identifier of the matrix row

rowValues - The values associated with the row

Throws:

IOException - If there are problems writing to the file.

writeLongMatrixColumn

public void writeLongMatrixColumn(int columnId,
                         long[] columnValues)
                           throws IOException

Description copied from class: Matrix

Write a column of the matrix to the underlying file.

Overrides:

writeLongMatrixColumn in class Matrix

Parameters:

columnId - The columnId for the matrix column

columnValues - Values associated with the column

Throws:

IOException - If there are problems writing to the file.

writeLongMatrixElement

public void writeLongMatrixElement(int rowId,
                          int columnId,
                          long value)
                            throws IOException

Description copied from class: Matrix

Write a specific matrix element code>[rowId, columnId] to the file.

Overrides:

writeLongMatrixElement in class Matrix

Parameters:

rowId - The row identifier for the element

columnId - The column identifier for the element

value - The value of the matrix element [rowId, columnId]

Throws:

IOException - If there are problems writing to the file.

writeLongMatrixRow

public void writeLongMatrixRow(int rowId,
                      long[] rowValues)
                        throws IOException

Description copied from class: Matrix

Write a row of the matrix to the underlying file.

Overrides:

writeLongMatrixRow in class Matrix

Parameters:

rowId - The identifier of the matrix row

rowValues - The values associated with the row

Throws:

IOException - If there are problems writing to the file.

main

public static void main(String[] args)

Parameters:

args -