org.apache.mahout.math

Class PivotedMatrix

java.lang.Object

org.apache.mahout.math.AbstractMatrix

org.apache.mahout.math.PivotedMatrix

All Implemented Interfaces:

Cloneable, Iterable<MatrixSlice>, Matrix, VectorIterable

public class PivotedMatrix
extends AbstractMatrix

Matrix that allows transparent row and column permutation.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.mahout.math.AbstractMatrix

AbstractMatrix.TransposeViewVector

Field Summary

Fields inherited from class org.apache.mahout.math.AbstractMatrix

COL, columnLabelBindings, columns, ROW, rowLabelBindings, rows

Constructor Summary

Constructors

Constructor and Description
PivotedMatrix(Matrix base)
PivotedMatrix(Matrix base, int[] pivot)
PivotedMatrix(Matrix base, int[] rowPivot, int[] columnPivot)

Method Summary

Methods

Modifier and Type	Method and Description
Matrix	assignColumn(int column, Vector other) Assign the other vector values to the column of the receiver
Matrix	assignRow(int row, Vector other) Assign the other vector values to the row of the receiver
Matrix	clone() Return a copy of the recipient
int	columnUnpivot(int k)
Matrix	getBase()
int[]	getColumnPivot()
int[]	getInverseColumnPivot()
int[]	getInverseRowPivot()
int[]	getNumNondefaultElements() Return the number of values in the recipient
double	getQuick(int row, int column) Return the value at the given indexes, without checking bounds
int[]	getRowPivot()
Matrix	like() Return an empty matrix of the same underlying class as the receiver
Matrix	like(int rows, int columns) Returns an empty matrix of the same underlying class as the receiver and of the specified size.
int	rowUnpivot(int k)
void	setQuick(int row, int column, double value) Set the value at the given index, without checking bounds
void	swap(int i, int j) Swaps indexes i and j.
void	swapColumns(int i, int j) Swaps indexes i and j.
void	swapRows(int i, int j) Swaps indexes i and j.
Vector	viewColumn(int column) Return the column at the given index
Matrix	viewPart(int[] offset, int[] size) Return a new matrix containing the subset of the recipient
Vector	viewRow(int row) Return the row at the given index

Methods inherited from class org.apache.mahout.math.AbstractMatrix

aggregate, aggregateColumns, aggregateRows, asFormatString, assign, assign, assign, assign, assign, columnSize, determinant, divide, get, get, getColumnLabelBindings, getFlavor, getRowLabelBindings, iterateAll, iterateNonEmpty, iterator, minus, numCols, numRows, numSlices, plus, plus, rowSize, set, set, set, set, set, set, setColumnLabelBindings, setRowLabelBindings, times, times, times, timesSquared, toString, transpose, viewDiagonal, viewPart, zSum

Methods inherited from class java.lang.Object

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

Constructor Detail

PivotedMatrix

public PivotedMatrix(Matrix base,
             int[] pivot)

PivotedMatrix

public PivotedMatrix(Matrix base,
             int[] rowPivot,
             int[] columnPivot)

PivotedMatrix

public PivotedMatrix(Matrix base)

Method Detail

swap

public void swap(int i,
        int j)

Swaps indexes i and j. This does both row and column permutation.

Parameters:

i - First index to swap.

j - Second index to swap.

swapRows

public void swapRows(int i,
            int j)

Swaps indexes i and j. This does just row permutation.

Parameters:

i - First index to swap.

j - Second index to swap.

swapColumns

public void swapColumns(int i,
               int j)

Swaps indexes i and j. This does just row permutation.

Parameters:

i - First index to swap.

j - Second index to swap.

assignColumn

public Matrix assignColumn(int column,
                  Vector other)

Assign the other vector values to the column of the receiver

Parameters:

column - the int row to assign

other - a Vector

Returns:

the modified receiver

Throws:

CardinalityException - if the cardinalities differ

assignRow

public Matrix assignRow(int row,
               Vector other)

Assign the other vector values to the row of the receiver

Parameters:

row - the int row to assign

other - a Vector

Returns:

the modified receiver

Throws:

CardinalityException - if the cardinalities differ

viewColumn

public Vector viewColumn(int column)

Return the column at the given index

Specified by:

viewColumn in interface Matrix

Overrides:

viewColumn in class AbstractMatrix

Parameters:

column - an int column index

Returns:

a Vector at the index

Throws:

IndexException - if the index is out of bounds

viewRow

public Vector viewRow(int row)

Return the row at the given index

Specified by:

viewRow in interface Matrix

Overrides:

viewRow in class AbstractMatrix

Parameters:

row - an int row index

Returns:

a Vector at the index

Throws:

IndexException - if the index is out of bounds

getQuick

public double getQuick(int row,
              int column)

Return the value at the given indexes, without checking bounds

Parameters:

row - an int row index

column - an int column index

Returns:

the double at the index

like

public Matrix like()

Return an empty matrix of the same underlying class as the receiver

Returns:

a Matrix

clone

public Matrix clone()

Description copied from interface: Matrix

Return a copy of the recipient

Specified by:

clone in interface Matrix

Overrides:

clone in class AbstractMatrix

Returns:

a new Matrix

like

public Matrix like(int rows,
          int columns)

Returns an empty matrix of the same underlying class as the receiver and of the specified size.

Parameters:

rows - the int number of rows

columns - the int number of columns

setQuick

public void setQuick(int row,
            int column,
            double value)

Set the value at the given index, without checking bounds

Parameters:

row - an int row index into the receiver

column - an int column index into the receiver

value - a double value to set

getNumNondefaultElements

public int[] getNumNondefaultElements()

Return the number of values in the recipient

Specified by:

getNumNondefaultElements in interface Matrix

Overrides:

getNumNondefaultElements in class AbstractMatrix

Returns:

an int[2] containing [row, column] count

viewPart

public Matrix viewPart(int[] offset,
              int[] size)

Return a new matrix containing the subset of the recipient

Specified by:

viewPart in interface Matrix

Overrides:

viewPart in class AbstractMatrix

Parameters:

offset - an int[2] offset into the receiver

size - the int[2] size of the desired result

Returns:

a new Matrix that is a view of the original

Throws:

CardinalityException - if the length is greater than the cardinality of the receiver

IndexException - if the offset is negative or the offset+length is outside of the receiver

rowUnpivot

public int rowUnpivot(int k)

columnUnpivot

public int columnUnpivot(int k)

getRowPivot

public int[] getRowPivot()

getInverseRowPivot

public int[] getInverseRowPivot()

getColumnPivot

public int[] getColumnPivot()

getInverseColumnPivot

public int[] getInverseColumnPivot()

getBase

public Matrix getBase()