org.apache.commons.geometry.euclidean.internal

Class Matrices

java.lang.Object

org.apache.commons.geometry.euclidean.internal.Matrices

public final class Matrices
extends Object

This class consists exclusively of static matrix utility methods.

Method Summary

Modifier and Type	Method and Description
static double	checkDeterminantForInverse(double det) Check that the given determinant is valid for use in calculating a matrix inverse.
static double	checkElementForInverse(double element) Check that the given matrix element is valid for use in calculation of a matrix inverse, throwing an IllegalStateException if not.
static double	determinant(double a00, double a01, double a10, double a11) Compute the determinant of the 2x2 matrix represented by the given values.
static double	determinant(double a00, double a01, double a02, double a10, double a11, double a12, double a20, double a21, double a22) Compute the determinant of the 3x3 matrix represented by the given values.

Methods inherited from class java.lang.Object

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

Method Detail

determinant

public static double determinant(double a00,
                                 double a01,
                                 double a10,
                                 double a11)

Compute the determinant of the 2x2 matrix represented by the given values. The values are listed in row-major order.

Parameters:

a00 - matrix entry a0,0

a01 - matrix entry a0,1

a10 - matrix entry a1,0

a11 - matrix entry a1,1

Returns:

computed 2x2 matrix determinant

determinant

public static double determinant(double a00,
                                 double a01,
                                 double a02,
                                 double a10,
                                 double a11,
                                 double a12,
                                 double a20,
                                 double a21,
                                 double a22)

Compute the determinant of the 3x3 matrix represented by the given values. The values are listed in row-major order.

Parameters:

a00 - matrix entry a0,0

a01 - matrix entry a0,1

a02 - matrix entry a0,2

a10 - matrix entry a1,0

a11 - matrix entry a1,1

a12 - matrix entry a1,2

a20 - matrix entry a2,0

a21 - matrix entry a2,1

a22 - matrix entry a2,2

Returns:

computed 3x3 matrix determinant

checkDeterminantForInverse

public static double checkDeterminantForInverse(double det)

Check that the given determinant is valid for use in calculating a matrix inverse. An IllegalStateException is thrown if the determinant is NaN, infinite, or zero.

Parameters:

det - the determinant to check

Returns:

the checked determinant

Throws:

IllegalStateException - if the matrix determinant value is NaN, infinite, or zero

checkElementForInverse

public static double checkElementForInverse(double element)

Check that the given matrix element is valid for use in calculation of a matrix inverse, throwing an IllegalStateException if not.

Parameters:

element - matrix entry to check

Returns:

the checked element

Throws:

IllegalStateException - if the element is not valid for use in calculating a matrix inverse, ie if it is NaN or infinite.