marf.math
Class Matrix

java.lang.Object
  |
  +--marf.math.Matrix

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

Vector

public class Matrix

extends java.lang.Object

implements java.lang.Cloneable

Algebraic operations on matrices. Adapted from my graphics project written in C++.

NOTE: this class provides a lot of useful and working functionality, but requires a lot of improvements. In particular in performance, documentation, and styles and consistency in operators. Some missing features will be added/filled in as well. Requires a lot of thorough testing.

$Id: Matrix.java,v 1.20 2005/06/01 01:57:16 mokhov Exp $

Since:

0.3.0

Version:

$Revision: 1.20 $

Author:

Serguei Mokhov

Nested Class Summary

protected class

Matrix.Direction Indicates the direction in which a matrix to be extended.

Field Summary

protected double[]	adMatrix Matrix itself.
static int	DEFAULT_COLS Default dimension of X of matrix is 4.
static int	DEFAULT_ROWS Default dimension of Y of matrix is 4.
protected int	iCols Actual number of columns in the matrix.
protected int	iRows Actual number of rows in the matrix.

Constructor Summary

Matrix()
Default constructor.

Matrix(double[] pad1DMatrix)
This constructor makes up a vector.

Matrix(double[][] padd2DMatrix)
Constructs a 2D matrix from a 2D array.

Matrix(double[] pad1DMatrix, boolean pbTransposed)
This constructor makes up a transposed vector.

Matrix(int piRows, int piCols)
Constructor with custom dimensions.

Matrix(int piRows, int piCols, double pdFillValue)
Constructor with custom dimensions and initial fill value.

Matrix(marf.math.Matrix poMatrix)
A-la copy-constructor.

Method Summary

static marf.math.Matrix	add(marf.math.Matrix poLHSMatrix, marf.math.Matrix poRHSMatrix) M3 = M1 + M2.
java.lang.Object	clone() Implements Clonable interface.
boolean	crop(int piLeft, int piTop, int piRight, int piBottom)
boolean	cutColumn(int piColNum) Shrinks a matrix by removing a specified colum from it.
boolean	cutRow(int piRowNum)
void	display() Outputs matrix in text format to STDOUT.
static void	divide(marf.math.Matrix poMatrix, double pdNum) M = M / d.
boolean	equals(marf.math.Matrix poMatrix) this == M.
static boolean	equals(marf.math.Matrix poLHSMatrix, marf.math.Matrix poRHSMatrix) M1 == M2.
void	exhaustMatrix() "Destroys" the internal array matrix by setting it to null.
boolean	extend(marf.math.Matrix poExtensionMatrix)
boolean	extend(marf.math.Matrix poExtensionMatrix, Matrix.Direction pDirection)
int	getCols()
double	getDeterminant() Calculates determinant of this matrix.
double	getElement(int piRow, int piCol)
int	getElements() Returns number of the elements of the matrix.
double[][]	getMatrix2D() Returns internal matrix representation as 2-dimensional array of doubles.
double[]	getMatrixArray()
static java.lang.String	getRevision() Retrieves class' revision.
int	getRows()
boolean	inverse() Matrix inversion.
boolean	isIdentity() Checks for strict identity matrix.
boolean	isNearlyIdentity()
boolean	isNearlyIdentity(double pdDelta)
boolean	isReduced()
void	loadRow(int piRowNum, marf.math.Vector poVector)
boolean	makeIdentity() Makes current matrix an identity one.
marf.math.Matrix	minus(marf.math.Matrix poMatrix) this - M.
static marf.math.Matrix	minus(marf.math.Matrix poLHSMatrix, marf.math.Matrix poRHSMatrix) M3 = M1 - M2.
static marf.math.Matrix	minusUnary(marf.math.Matrix poMatrix) M = -M.
void	multiply(double pdNum) this = this * d.
static void	multiply(double pdNum, marf.math.Matrix poMatrix) M1 = d * M.
marf.math.Matrix	multiply(marf.math.Matrix poMatrix) M1 = this * M.
static void	multiply(marf.math.Matrix poMatrix, double pdNum) M = M * d.
static marf.math.Matrix	multiply(marf.math.Matrix poLHSMatrix, marf.math.Matrix poRHSMatrix) M3 = M1 * M2.
boolean	rowOperation(double pdA, int piRc)
boolean	rowOperation(double piA, int piRc, char pcOp, double piB, int piRp)
boolean	rowReduce()
void	setAll() Default of 0.0.
void	setAll(double pdFillValue) Sets all elements of the matrix to the specified value.
void	setCols(int piCols)
void	setElement(int piRow, int piCol, double pdValue)
void	setMatrix2D(double[][] padd2DMatrix) Sets internal array based on 2-dimensional parameter.
void	setMatrixArray(double[] padNewMatrix)
void	setRows(int piRows)
int	size() Analoguous to getElements().
java.lang.String	toString() Textual representation of the matrix.
boolean	transpose() Matrix transpose.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_ROWS

public static final int DEFAULT_ROWS

Default dimension of Y of matrix is 4.

See Also:

Constant Field Values

DEFAULT_COLS

public static final int DEFAULT_COLS

Default dimension of X of matrix is 4.

See Also:

Constant Field Values

iRows

protected int iRows

Actual number of rows in the matrix.

iCols

protected int iCols

Actual number of columns in the matrix.

adMatrix

protected double[] adMatrix

Matrix itself.

Constructor Detail

Matrix

public Matrix()

Default constructor. Equivalent to Matrix(Matrix.DEFAULT_ROWS, Matrix.DEFAULT_COLS).

Matrix

public Matrix(int piRows,
              int piCols)

Constructor with custom dimensions. Equivalent to Matrix(piRows, piCols, 0.0).

Parameters:

piRows - custom # of rows.

piCols - custom # of columns.

Matrix

public Matrix(int piRows,
              int piCols,
              double pdFillValue)

Constructor with custom dimensions and initial fill value.

Parameters:

piRows - custom # of rows.

piCols - custom # of columns.

pdFillValue - initial value of all the elements of the matrix.

Matrix

public Matrix(marf.math.Matrix poMatrix)

A-la copy-constructor.

Parameters:

poMatrix - Matrix object to copy data members off from

Matrix

public Matrix(double[] pad1DMatrix)

This constructor makes up a vector. Equivalent to Matrix(pad1DMatrix, false).

Parameters:

pad1DMatrix - vector's elements

Matrix

public Matrix(double[] pad1DMatrix,
              boolean pbTransposed)

This constructor makes up a transposed vector.

Parameters:

pad1DMatrix - vector's elements

pbTransposed - true if transposed, false otherwise

Matrix

public Matrix(double[][] padd2DMatrix)

Constructs a 2D matrix from a 2D array. Internally calls setMatrix2D().

Parameters:

padd2DMatrix - initial array elements

See Also:

setMatrix2D(double[][])

Method Detail

exhaustMatrix

public void exhaustMatrix()

"Destroys" the internal array matrix by setting it to null. Part of the leftover API from the C++ code.

getRows

public final int getRows()

Returns:

number of rows

getCols

public final int getCols()

Returns:

number of columns

setRows

public void setRows(int piRows)

setCols

public void setCols(int piCols)

getMatrixArray

public final double[] getMatrixArray()

setMatrixArray

public void setMatrixArray(double[] padNewMatrix)

setAll

public void setAll()

Default of 0.0.

setAll

public void setAll(double pdFillValue)

Sets all elements of the matrix to the specified value.

getElements

public final int getElements()

Returns number of the elements of the matrix. Part of the original C++ API.

size

public final int size()

Analoguous to getElements().

Since:

0.3.0

getElement

public final double getElement(int piRow,
                               int piCol)

Throws:

java.lang.ArrayIndexOutOfBoundsException

setElement

public void setElement(int piRow,
                       int piCol,
                       double pdValue)

Throws:

java.lang.ArrayIndexOutOfBoundsException

loadRow

public void loadRow(int piRowNum,
                    marf.math.Vector poVector)

getDeterminant

public final double getDeterminant()

Calculates determinant of this matrix.

rowOperation

public boolean rowOperation(double pdA,
                            int piRc)

rowOperation

public boolean rowOperation(double piA,
                            int piRc,
                            char pcOp,
                            double piB,
                            int piRp)

rowReduce

public boolean rowReduce()

isReduced

public boolean isReduced()

extend

public boolean extend(marf.math.Matrix poExtensionMatrix)

extend

public boolean extend(marf.math.Matrix poExtensionMatrix,
                      Matrix.Direction pDirection)

crop

public boolean crop(int piLeft,
                    int piTop,
                    int piRight,
                    int piBottom)

cutRow

public boolean cutRow(int piRowNum)

cutColumn

public boolean cutColumn(int piColNum)

Shrinks a matrix by removing a specified colum from it.

Parameters:

piColNum - a valid index of the column to be removed.

Returns:

true if the column was actually removed; false otherwise

display

public void display()

Outputs matrix in text format to STDOUT.

toString

public java.lang.String toString()

Textual representation of the matrix.

Overrides:

toString in class java.lang.Object

Returns:

String representation

inverse

public boolean inverse()

Matrix inversion.

Returns:

true if matrix was reduced, false otherwise

transpose

public boolean transpose()

Matrix transpose.

Returns:

true if matrix was transposed, false otherwise

makeIdentity

public boolean makeIdentity()

Makes current matrix an identity one.

isIdentity

public final boolean isIdentity()

Checks for strict identity matrix. Any diviations due to errors in floarting point arithmetic will return false.

isNearlyIdentity

public final boolean isNearlyIdentity(double pdDelta)

isNearlyIdentity

public final boolean isNearlyIdentity()

add

public static marf.math.Matrix add(marf.math.Matrix poLHSMatrix,
                                   marf.math.Matrix poRHSMatrix)

M3 = M1 + M2.

minus

public static marf.math.Matrix minus(marf.math.Matrix poLHSMatrix,
                                     marf.math.Matrix poRHSMatrix)

M3 = M1 - M2.

minusUnary

public static marf.math.Matrix minusUnary(marf.math.Matrix poMatrix)

M = -M.

minus

public marf.math.Matrix minus(marf.math.Matrix poMatrix)

this - M.

multiply

public marf.math.Matrix multiply(marf.math.Matrix poMatrix)

M1 = this * M.

multiply

public static marf.math.Matrix multiply(marf.math.Matrix poLHSMatrix,
                                        marf.math.Matrix poRHSMatrix)

M3 = M1 * M2.

multiply

public static void multiply(marf.math.Matrix poMatrix,
                            double pdNum)

M = M * d.

multiply

public void multiply(double pdNum)

this = this * d.

multiply

public static void multiply(double pdNum,
                            marf.math.Matrix poMatrix)

M1 = d * M.

divide

public static void divide(marf.math.Matrix poMatrix,
                          double pdNum)

M = M / d.

equals

public boolean equals(marf.math.Matrix poMatrix)

this == M.

equals

public static boolean equals(marf.math.Matrix poLHSMatrix,
                             marf.math.Matrix poRHSMatrix)

M1 == M2.

getMatrix2D

public double[][] getMatrix2D()

Returns internal matrix representation as 2-dimensional array of doubles.

setMatrix2D

public void setMatrix2D(double[][] padd2DMatrix)

Sets internal array based on 2-dimensional parameter. Works under assumptions that all rows are of the same length.

clone

public java.lang.Object clone()

Implements Clonable interface. Creates a deep copy of the object by cloning the internal matrix array.

Overrides:

clone in class java.lang.Object

getRevision

public static java.lang.String getRevision()

Retrieves class' revision.

Returns:

revision string