net.java.dev.joode.util
Class Matrix

java.lang.Object
  net.java.dev.joode.util.Real
      net.java.dev.joode.util.Matrix

Direct Known Subclasses:

Matrix3, Matrix4

public class Matrix
extends Real

A common AxB Matrix The matrix will always be an identity matrix on instatiation.

Author:

Arne Mueller

Field Summary

Fields inherited from class net.java.dev.joode.util.Real

m

Constructor Summary

Matrix(int columns, int rows)
creates a rows x cols Matrix

Method Summary

static Matrix	aquireInstance(int columns, int rows) gets a pooled instance.
static boolean	epsilonEquals(Matrix a, Matrix b, float e)
float	get(int column, int row)
Real	getColumn(int i)
Real	getColumn(int i, Real passback)
int	getColumns()
void	getRow(int i, Real v)
int	getRows()
Matrix	mul(Matrix C) Matrix Operation: A = B * C
void	mul(Matrix C, Matrix A) Matrix Operation: A = B * C
Real	mul(Real c) Matrix-Vector Operation: a = B * c
Real	mulInc(Real c, Real a) Matrix-Vector Operation: a += B * c
Matrix	mulTranspose(Matrix C) Matrix Operation: A = B * C'
void	mulTranspose(Matrix C, Matrix A) Matrix Operation: A = B * C'
static void	releaseInstance(Matrix instance) returns a matrix into the object pool for a caller of aquireInstance.
void	set(int column, int row, float value)
void	setColumn(int i, Real v)
void	setIdentity()
void	setRow(int i, Real v)
static boolean	solve(Matrix A, Real b, Real passback) performs gaussian elimination with parial pivoting.
java.lang.String	toString()
void	transpose() transposes this matrix in place (garbageless)
void	transposeMul(Matrix C, Matrix A) Matrix Operation: A = B' * C
Real	transposeMul(Real c) Matrix-Vector Operation: a = B' * c Note that the transpose of an orthanormal matrix, such as a rotation matrix, is the inverse matrix
Real	transposeMul(Real c, Real a) Matrix-Vector Operation: a += B' * c Note that the transpose of an orthanormal matrix, such as a rotation matrix, is the inverse matrix

Methods inherited from class net.java.dev.joode.util.Real

add, aquireDirtyInstance, aquireInstance, dot, dot, epsilonEquals, epsilonEquals, fill, get, length, lengthSquared, max, min, norm, normalize, releaseInstance, scale, set, set, setZero, size, sub

Methods inherited from class java.lang.Object

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

Constructor Detail

Matrix

public Matrix(int columns,
              int rows)

creates a rows x cols Matrix

Method Detail

aquireInstance

public static Matrix aquireInstance(int columns,
                                    int rows)

gets a pooled instance. Return the object with releaseInstance. Matrix is initialized to identity

Parameters:

columns -

rows -

Returns:

releaseInstance

public static void releaseInstance(Matrix instance)

returns a matrix into the object pool for a caller of aquireInstance.

getColumns

public int getColumns()

getRows

public int getRows()

get

public float get(int column,
                 int row)

set

public void set(int column,
                int row,
                float value)

getColumn

public Real getColumn(int i)

getColumn

public Real getColumn(int i,
                      Real passback)

setColumn

public void setColumn(int i,
                      Real v)

getRow

public void getRow(int i,
                   Real v)

setRow

public void setRow(int i,
                   Real v)

setIdentity

public void setIdentity()

mul

public Real mul(Real c)

Matrix-Vector Operation: a = B * c

Parameters:

c - Vector c

Returns:

Vector a grabage creating!

mulInc

public Real mulInc(Real c,
                   Real a)

Matrix-Vector Operation: a += B * c

Parameters:

c - Vector c

a - Vector a, contains the result

transposeMul

public Real transposeMul(Real c)

Matrix-Vector Operation: a = B' * c Note that the transpose of an orthanormal matrix, such as a rotation matrix, is the inverse matrix

Parameters:

c - Vector c

Returns:

Vector a

transposeMul

public Real transposeMul(Real c,
                         Real a)

Matrix-Vector Operation: a += B' * c Note that the transpose of an orthanormal matrix, such as a rotation matrix, is the inverse matrix

Parameters:

c - Vector c

a - Vector a, contains result

transpose

public void transpose()

transposes this matrix in place (garbageless)

mul

public Matrix mul(Matrix C)

Matrix Operation: A = B * C

Parameters:

C - Matrix C

Returns:

Matrix A

mul

public void mul(Matrix C,
                Matrix A)

Matrix Operation: A = B * C

Parameters:

C - Matrix C

A - Matrix A, contains the result

mulTranspose

public Matrix mulTranspose(Matrix C)

Matrix Operation: A = B * C'

Parameters:

C - Matrix C

Returns:

Matrix A

mulTranspose

public void mulTranspose(Matrix C,
                         Matrix A)

Matrix Operation: A = B * C'

Parameters:

C - Matrix C

A - Matrix A, contains the result

transposeMul

public void transposeMul(Matrix C,
                         Matrix A)

Matrix Operation: A = B' * C

Parameters:

C - Matrix C

A - Matrix A, contains the result

epsilonEquals

public static boolean epsilonEquals(Matrix a,
                                    Matrix b,
                                    float e)

toString

public java.lang.String toString()

Overrides:

toString in class Real

solve

public static boolean solve(Matrix A,
                            Real b,
                            Real passback)

performs gaussian elimination with parial pivoting. Input matrix must be a square matrix, input RHS must be a vector of the same size. the passback bust be the size of the matrix. Each equation should be encoded as a row of the matrix eg 2x + 3y = 7 5x - 3y = 8 [2, 3 5,-3] = [7,8]' [cooeffecients] = [rhs] the result, passback, will contain instanciationsof the unkowns that satisfy the equations or if degenerate, the method will return false DO NOT USE WITH Vector3 and Matrix3 becuase their sizes are inconsistent

Returns: