Package pulse.math.linear

Class SquareMatrix

java.lang.Object

pulse.math.linear.RectangularMatrix

pulse.math.linear.SquareMatrix

All Implemented Interfaces:

Serializable

public class SquareMatrix
extends RectangularMatrix

The matrix class.

Used for operations on small matrices primarily in optimisation and Runge-Kutta calculations of radiative transfer. Fixed-size matrices of size 2, 3, and 4 are the direct subclasses and offer a boost in performance by implementing a reduced FLOP matrix inverse.

Note this class cannot be instantiated directly from outside the pulse.math package, the user needs to invoke the factory class methods Matrices instead.

See Also:

Matrices, Serialized Form

Field Summary

Fields inherited from class pulse.math.linear.RectangularMatrix

x

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	SquareMatrix(double[][] args)	Constructs a Matrix with the elements copied from args.

Method Summary

Modifier and Type	Method	Description
static SquareMatrix	asSquareMatrix(RectangularMatrix m)
SquareMatrix	blockDiagonal()	Creates a block-diagonal matrix from the diagonal of this matrix.
double	det()	Calculates the determinant for an n-by-n square matrix.
int	dimension()
SquareMatrix	inverse()	Conducts matrix inversion with the procedural EJML approach.
boolean	isPositiveDefinite()	Checks if a matrix is positive definite.
static SquareMatrix	outerProduct(Vector a, Vector b)	Calculates the outer product of two vectors.

Methods inherited from class pulse.math.linear.RectangularMatrix

dimensionsMatch, equals, get, getData, multiply, multiply, multiply, subtract, sum, toString, transpose

Methods inherited from class java.lang.Object

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

Constructor Detail

SquareMatrix

protected SquareMatrix(double[][] args)

Constructs a Matrix with the elements copied from args. The elements are copied by invoking System.arraycopy(...).

Parameters:

args - a two-dimensional double array

Method Detail

det

public double det()

Calculates the determinant for an n-by-n square matrix. The determinant is calculated using the EJML library.

Returns:

a double, representing the determinant

inverse

public SquareMatrix inverse()

Conducts matrix inversion with the procedural EJML approach. Can be overriden by subclasses to boost performance.

Returns:

the inverted .

isPositiveDefinite

public boolean isPositiveDefinite()

Checks if a matrix is positive definite. Uses EJML implementation.

Returns:

true is positive-definite

outerProduct

public static SquareMatrix outerProduct(Vector a,
                                        Vector b)

Calculates the outer product of two vectors.

Parameters:

a - a Vector

b - a Vector

Returns:

the outer product of a and b

asSquareMatrix

public static SquareMatrix asSquareMatrix(RectangularMatrix m)

dimension

public int dimension()

blockDiagonal

public SquareMatrix blockDiagonal()

Creates a block-diagonal matrix from the diagonal of this matrix.

Returns:

diag(this)