org.gephi.lib.gleem.linalg

Class Mat2f

java.lang.Object

org.gephi.lib.gleem.linalg.Mat2f

public class Mat2f
extends Object

2x2 matrix class useful for simple linear algebra. Representation is (as Mat4f) in row major order and assumes multiplication by column vectors on the right.

Field Summary

Fields

Modifier and Type	Field and Description
private float[]	data

Constructor Summary

Constructors

Constructor and Description
Mat2f() Creates new matrix initialized to the zero matrix

Method Summary

Methods

Modifier and Type	Method and Description
float	determinant() Return the determinant.
float	get(int i, int j) Gets the (i,j)th element of this matrix, where i is the row index and j is the column index
boolean	invert() Full matrix inversion in place.
void	makeIdent() Initialize to the identity matrix.
Mat2f	mul(Mat2f b) Returns this * b; creates new matrix
void	mul(Mat2f a, Mat2f b) this = a * b
void	set(int i, int j, float val) Sets the (i,j)th element of this matrix, where i is the row index and j is the column index
void	setCol(int i, Vec2f v) Set column i (i=[0..1]) to vector v.
void	setRow(int i, Vec2f v) Set row i (i=[0..1]) to vector v.
Matf	toMatf()
String	toString()
void	transpose() Transpose this matrix in place.
void	xformVec(Vec2f src, Vec2f dest) Multiply a 2D vector by this matrix.

Methods inherited from class java.lang.Object

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

Field Detail

data

private float[] data

Constructor Detail

Mat2f

public Mat2f()

Creates new matrix initialized to the zero matrix

Method Detail

makeIdent

public void makeIdent()

Initialize to the identity matrix.

get

public float get(int i,
        int j)

Gets the (i,j)th element of this matrix, where i is the row index and j is the column index

set

public void set(int i,
       int j,
       float val)

Sets the (i,j)th element of this matrix, where i is the row index and j is the column index

setCol

public void setCol(int i,
          Vec2f v)

Set column i (i=[0..1]) to vector v.

setRow

public void setRow(int i,
          Vec2f v)

Set row i (i=[0..1]) to vector v.

transpose

public void transpose()

Transpose this matrix in place.

determinant

public float determinant()

Return the determinant.

invert

public boolean invert()

Full matrix inversion in place. If matrix is singular, returns false and matrix contents are untouched. If you know the matrix is orthonormal, you can call transpose() instead.

xformVec

public void xformVec(Vec2f src,
            Vec2f dest)

Multiply a 2D vector by this matrix. NOTE: src and dest must be different vectors.

mul

public Mat2f mul(Mat2f b)

Returns this * b; creates new matrix

mul

public void mul(Mat2f a,
       Mat2f b)

this = a * b

toMatf

public Matf toMatf()

toString

public String toString()

Overrides:

toString in class Object