edu.ucla.sspace.matrix

Class AtomicGrowingMatrix

java.lang.Object

edu.ucla.sspace.matrix.AtomicGrowingMatrix

All Implemented Interfaces:

AtomicMatrix, Matrix

public class AtomicGrowingMatrix
extends Object
implements AtomicMatrix

A concurrent, thread-safe, growable Matrix class. This class allows multiple threads to operate on the same matrix where all methods are concurrent to the fullest extent possible.

Author:

David Jurgens

Nested Class Summary

Nested classes/interfaces inherited from interface edu.ucla.sspace.matrix.Matrix

Matrix.Type

Constructor Summary

Constructors

Constructor and Description
AtomicGrowingMatrix() Create an AtomicGrowingMatrix with 0 rows and 0 columns.

Method Summary

Methods

Modifier and Type	Method and Description
double	addAndGet(int row, int col, double delta) Return the value stored at (row, col) plus delta, and then increment the specified cell by delta.
int	columns() Returns the number of columns in this Matrix.
double	get(int row, int col) Returns the value of the Matrix at the provided row and column.
double	getAndAdd(int row, int col, double delta) Return the value stored at (row, col), and add delta to the same index.
double[]	getColumn(int column) Returns the entire column.
DoubleVector	getColumnVector(int column) Returns the column as a vector.
DoubleVector	getColumnVectorUnsafe(int column) Returns an immutable view of the columns's data as a non-atomic vector, which may present an inconsistent view of the data if this matrix is being concurrently modified.
double[]	getRow(int row) Returns the entire row.
DoubleVector	getRowVector(int row) Returns a DoubleVector for an entire row.
DoubleVector	getRowVectorUnsafe(int row) Returns an immutable view of the row's data as a non-atomic vector, which may present an inconsistent view of the data if this matrix is being concurrently modified.
int	rows() Returns the number of rows in this Matrix.
void	set(int row, int col, double val) Sets the location at the row and column to the provided value.
void	setColumn(int column, double[] values) Sets the values for the column of this Matrix using the provided array.
void	setColumn(int column, DoubleVector values) Sets the values for the column of this Matrix using the provided DoubleVector.
void	setRow(int row, double[] columns) Sets the values for the row of this Matrix using the provided array.
void	setRow(int row, DoubleVector values) Sets the values for the row of this Matrix using the provided DoubleVector.
double[][]	toDenseArray() Converts the Matrix to a two dimensional array.

Methods inherited from class java.lang.Object

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

Constructor Detail

AtomicGrowingMatrix

public AtomicGrowingMatrix()

Create an AtomicGrowingMatrix with 0 rows and 0 columns.

Method Detail

addAndGet

public double addAndGet(int row,
               int col,
               double delta)

Return the value stored at (row, col) plus delta, and then increment the specified cell by delta.

Specified by:

addAndGet in interface AtomicMatrix

Parameters:

row - The row of the cell to modify and return.

col - The column of the cell to modify and return.

delta - The amount to change the specified cell.

Returns:

The value of the cell at (row, col) after adding delta.

columns

public int columns()

Returns the number of columns in this Matrix.

Specified by:

columns in interface Matrix

Returns:

The number of columns in this Matrix.

get

public double get(int row,
         int col)

Returns the value of the Matrix at the provided row and column.

Specified by:

get in interface Matrix

Parameters:

row - The row values of the cell to return.

col - The column value of the cell to return.

Returns:

The value at the cell specified by row and col.

getAndAdd

public double getAndAdd(int row,
               int col,
               double delta)

Return the value stored at (row, col), and add delta to the same index.

Specified by:

getAndAdd in interface AtomicMatrix

Parameters:

row - The row of the cell to return and modify.

col - The column of the cell to return and modify.

delta - The amount to change the specified cell.

Returns:

The value of the cell at (row, col) prior to adding delta.

getColumn

public double[] getColumn(int column)

Returns the entire column. The length of the returned column reflects the size of matrix at the time of the call, which may be different from earlier calls to rows()

Specified by:

getColumn in interface Matrix

Parameters:

column - The column to return an array for.

Returns:

A double array representing the column at column.

getColumnVector

public DoubleVector getColumnVector(int column)

Returns the column as a vector. Whether updates to the vector are written through to the backing matrix is left open to the specific implementation. Implementations that maintain their data in a sparse format are encouraged to return a SparseVector instance. The length of the returned row vector reflects the size of matrix at the time of the call, which may be different from earlier calls to rows()

Specified by:

getColumnVector in interface Matrix

Parameters:

column - The column to return a DoubleVector for.

Returns:

A DoubleVector representing the column at column.

getColumnVectorUnsafe

public DoubleVector getColumnVectorUnsafe(int column)

Returns an immutable view of the columns's data as a non-atomic vector, which may present an inconsistent view of the data if this matrix is being concurrently modified. This method should only be used in special cases where the vector is being accessed at a time when the matrix (or this particular row) will not be modified.

getRow

public double[] getRow(int row)

Returns the entire row. The length of the returned row reflects the size of matrix at the time of the call, which may be different from earlier calls to columns().

Specified by:

getRow in interface Matrix

Parameters:

row - The row to return an array for.

Returns:

A double array representing the row at row.

getRowVector

public DoubleVector getRowVector(int row)

Returns a DoubleVector for an entire row. Implementations should return an approriately typed DoubleVector. Whether updates to the vector are written through to the backing matrix is left open to the specific implementation. Implementations that maintain their data in a sparse format are encouraged to return a SparseVector instance. The length of the returned row vector reflects the size of matrix at the time of the call, which may be different from earlier calls to columns().

Specified by:

getRowVector in interface Matrix

Parameters:

row - the index of the row to return.

Returns:

A DoubleVector representing the row at row.

getRowVectorUnsafe

public DoubleVector getRowVectorUnsafe(int row)

Returns an immutable view of the row's data as a non-atomic vector, which may present an inconsistent view of the data if this matrix is being concurrently modified. This method should only be used in special cases where the vector is being accessed at a time when the matrix (or this particular row) will not be modified.

Parameters:

row - the row whose values should be returned

Returns:

an unsafe, non-atomic view of the row's data

rows

public int rows()

Returns the number of rows in this Matrix.

Specified by:

rows in interface Matrix

Returns:

The number of columns in this Matrix.

set

public void set(int row,
       int col,
       double val)

Sets the location at the row and column to the provided value.

Specified by:

set in interface Matrix

Parameters:

row - The row of the cell to update.

col - The column of the cell to update.

val - The new value of the specified cell.

setColumn

public void setColumn(int column,
             double[] values)

Sets the values for the column of this Matrix using the provided array. Note that the array itself is not made internal to the instance itself.

Specified by:

setColumn in interface Matrix

Parameters:

column - The column to update.

values - The values to update into column.

setColumn

public void setColumn(int column,
             DoubleVector values)

Sets the values for the column of this Matrix using the provided DoubleVector. Note that the DoubleVector itself is not made internal to the instance itself.

Specified by:

setColumn in interface Matrix

Parameters:

column - The column to update.

values - The values to update into column.

setRow

public void setRow(int row,
          double[] columns)

Sets the values for the row of this Matrix using the provided array. Note that the array itself is not made internal to the instance itself.

Specified by:

setRow in interface Matrix

Parameters:

row - The row to update.

columns - The values to update into row.

setRow

public void setRow(int row,
          DoubleVector values)

Sets the values for the row of this Matrix using the provided DoubleVector. Note that the DoubleVector itself is not made internal to the instance itself.

Specified by:

setRow in interface Matrix

Parameters:

row - The row to update.

values - The values to update into row.

toDenseArray

public double[][] toDenseArray()

Converts the Matrix to a two dimensional array. Note that for large matrices, this may exhaust all available memory.

Specified by:

toDenseArray in interface Matrix

Returns:

A double array version of this Matrix.