org.bouncycastle.pqc.legacy.math.linearalgebra
Class GF2mMatrix

java.lang.Object
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  +--org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix
        |
        +--org.bouncycastle.pqc.legacy.math.linearalgebra.GF2mMatrix

public class GF2mMatrix

extends Matrix

This class describes some operations with matrices over finite field GF(2 m) with small m (1< m <32).

See Also:

Matrix

Field Summary

protected GF2mField	field finite field GF(2^m)
protected int[][]	matrix For the matrix representation the array of type int[][] is used, thus every element of the array keeps one element of the matrix (element from finite field GF(2^m))

Fields inherited from class org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

MATRIX_TYPE_RANDOM_LT, MATRIX_TYPE_RANDOM_REGULAR, MATRIX_TYPE_RANDOM_UT, MATRIX_TYPE_UNIT, MATRIX_TYPE_ZERO, numColumns, numRows

Constructor Summary

	GF2mMatrix(GF2mField field, byte[] enc) Constructor.
protected	GF2mMatrix(GF2mField field, int[][] matrix) Constructor.
	GF2mMatrix(GF2mMatrix other) Copy constructor.

Method Summary

Matrix	computeInverse() Compute the inverse of this matrix.
boolean	equals(java.lang.Object other) Checks if given object is equal to this matrix.
byte[]	getEncoded()
int	hashCode()
boolean	isZero() Check if this is the zero matrix (i.e., all entries are zero).
Vector	leftMultiply(Vector vector) Compute the product of a vector and this matrix.
Matrix	rightMultiply(Matrix a) Compute the product of this matrix and another matrix.
Matrix	rightMultiply(Permutation perm) Compute the product of this matrix and a permutation.
Vector	rightMultiply(Vector vector) Compute the product of this matrix and a vector.
java.lang.String	toString()

Methods inherited from class org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

getNumColumns, getNumRows

Methods inherited from class java.lang.Object

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

Field Detail

field

protected GF2mField field

finite field GF(2^m)

matrix

protected int[][] matrix

For the matrix representation the array of type int[][] is used, thus every element of the array keeps one element of the matrix (element from finite field GF(2^m))

Constructor Detail

GF2mMatrix

public GF2mMatrix(GF2mField field,
                  byte[] enc)

Constructor.

Parameters:

field - a finite field GF(2^m)

enc - byte[] matrix in byte array form

GF2mMatrix

public GF2mMatrix(GF2mMatrix other)

Copy constructor.

Parameters:

other - another GF2mMatrix

GF2mMatrix

protected GF2mMatrix(GF2mField field,
                     int[][] matrix)

Constructor.

Parameters:

field - a finite field GF(2^m)

matrix - the matrix as int array. Only the reference is copied.

Method Detail

getEncoded

public byte[] getEncoded()

Overrides:

getEncoded in class Matrix

Returns:

a byte array encoding of this matrix

isZero

public boolean isZero()

Check if this is the zero matrix (i.e., all entries are zero).

Overrides:

isZero in class Matrix

Returns:

true if this is the zero matrix

computeInverse

public Matrix computeInverse()

Compute the inverse of this matrix.

Overrides:

computeInverse in class Matrix

Returns:

the inverse of this matrix (newly created).

rightMultiply

public Matrix rightMultiply(Matrix a)

Description copied from class: Matrix

Compute the product of this matrix and another matrix.

Overrides:

rightMultiply in class Matrix

Following copied from class: org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

Parameters:

a - the other matrix

Returns:

this * a (newly created)

rightMultiply

public Matrix rightMultiply(Permutation perm)

Description copied from class: Matrix

Compute the product of this matrix and a permutation.

Overrides:

rightMultiply in class Matrix

Following copied from class: org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

Parameters:

p - the permutation

Returns:

this * p (newly created)

leftMultiply

public Vector leftMultiply(Vector vector)

Description copied from class: Matrix

Compute the product of a vector and this matrix. If the length of the vector is greater than the number of rows of this matrix, the matrix is multiplied by each m-bit part of the vector.

Overrides:

leftMultiply in class Matrix

Following copied from class: org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

Parameters:

vector - a vector

Returns:

vector * this (newly created)

rightMultiply

public Vector rightMultiply(Vector vector)

Description copied from class: Matrix

Compute the product of this matrix and a vector.

Overrides:

rightMultiply in class Matrix

Following copied from class: org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

Parameters:

vector - a vector

Returns:

this * vector (newly created)

equals

public boolean equals(java.lang.Object other)

Checks if given object is equal to this matrix. The method returns false whenever the given object is not a matrix over GF(2^m).

Overrides:

equals in class java.lang.Object

Parameters:

other - object

Returns:

true or false

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class Matrix

Following copied from class: org.bouncycastle.pqc.legacy.math.linearalgebra.Matrix

Returns:

a human readable form of the matrix.