edu.ucla.sspace.matrix

Class RowScaledSparseMatrix

java.lang.Object

edu.ucla.sspace.matrix.RowScaledMatrix

edu.ucla.sspace.matrix.RowScaledSparseMatrix

All Implemented Interfaces:

Matrix, SparseMatrix

public class RowScaledSparseMatrix
extends RowScaledMatrix
implements SparseMatrix

A decorator over SparseMatrixs. Each row can be scaled by some scalar constant in O(1) time by applying the scalar value for each row during all gets and sets to values in the row.

Author:

Keith Stevens

Nested Class Summary

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

Matrix.Type

Constructor Summary

Constructors

Constructor and Description
RowScaledSparseMatrix(SparseMatrix matrix, DoubleVector v) Creates a RowScaledSparseMatrix that provides scaled read only access to the provided SparseMatrix instance.

Method Summary

Methods

Modifier and Type	Method and Description
SparseDoubleVector	getColumnVector(int row) Returns the column as a vector.
SparseDoubleVector	getRowVector(int row) Returns a DoubleVector for an entire row.

Methods inherited from class edu.ucla.sspace.matrix.RowScaledMatrix

columns, get, getColumn, getRow, rows, set, setColumn, setColumn, setRow, setRow, toDenseArray

Methods inherited from class java.lang.Object

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

Methods inherited from interface edu.ucla.sspace.matrix.Matrix

columns, get, getColumn, getRow, rows, set, setColumn, setColumn, setRow, setRow, toDenseArray

Constructor Detail

RowScaledSparseMatrix

public RowScaledSparseMatrix(SparseMatrix matrix,
                     DoubleVector v)

Creates a RowScaledSparseMatrix that provides scaled read only access to the provided SparseMatrix instance.

Method Detail

getColumnVector

public SparseDoubleVector getColumnVector(int row)

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.

Specified by:

getColumnVector in interface Matrix

Specified by:

getColumnVector in interface SparseMatrix

Overrides:

getColumnVector in class RowScaledMatrix

Parameters:

row - The column to return a DoubleVector for.

Returns:

A DoubleVector representing the column at column.

getRowVector

public SparseDoubleVector 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.

Specified by:

getRowVector in interface Matrix

Specified by:

getRowVector in interface SparseMatrix

Overrides:

getRowVector in class RowScaledMatrix

Parameters:

row - the index of the row to return.

Returns:

A DoubleVector representing the row at row.