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Interface Field<E extends Element>

All Known Subinterfaces:

FieldOver<F,E>

public interface Field<E extends Element>

Represents an algebraic structure.

Since:

1.0.0

Author:

Angelo De Caro (jpbclib@gmail.com)

See Also:

Element, ElementPowPreProcessing

Method Summary

Methods

Modifier and Type	Method and Description
Element[]	add(Element[] a, Element[] b) Computes the component-wise addition between a and b.
int	getCanonicalRepresentationLengthInBytes() Returns the length in bytes needed to canonical represent an element of this Field.
ElementPowPreProcessing	getElementPowPreProcessingFromBytes(byte[] source) Reads an ElementPowPreProcessing from the buffer source.
ElementPowPreProcessing	getElementPowPreProcessingFromBytes(byte[] source, int offset) Reads an ElementPowPreProcessing from the buffer source starting from offset.
int	getLengthInBytes() Returns the length in bytes needed to represent an element of this Field.
int	getLengthInBytes(Element e) Returns the length in bytes needed to represent an element of this Field.
E	getNqr() Returns a quadratic non-residue in this field.
BigInteger	getOrder() Returns the order of this field.
boolean	isOrderOdd() Returns true> if the order is odd, false otherwise.
E	newElement() Returns a new element which lies in this field.
E	newElement(BigInteger value) Returns a new element whose value is passed as parameter.
E	newElement(E e) Returns a new element whose value is copied from the passed element.
E	newElement(int value) Returns a new element whose value is passed as parameter.
E	newElementFromBytes(byte[] source) Returns a new element whose value is set from the buffer source.
E	newElementFromBytes(byte[] source, int offset) Returns a new element whose value is set from the buffer source starting from offset.
E	newElementFromHash(byte[] source, int offset, int length) Returns a new element whose value is set deterministically from the length bytes stored in the source parameter starting from the passed offset.
E	newOneElement() Returns a new element whose value is one.
E	newRandomElement() Returns a new random element.
E	newZeroElement() Returns a new element whose value is zero.
Element[]	twice(Element[] elements) Computes the component-wise twice.

Method Detail

newElement

E newElement()

Returns a new element which lies in this field.

Returns:

a new element which lies in this field.

Since:

1.0.0

newElement

E newElement(int value)

Returns a new element whose value is passed as parameter.

Parameters:

value - the value of the new element.

Returns:

a new element whose value is passed as parameter.

Since:

1.0.0

See Also:

Element.set(int)

newElement

E newElement(BigInteger value)

Returns a new element whose value is passed as parameter.

Parameters:

value - the value of the new element.

Returns:

a new element whose value is passed as parameter.

Since:

1.0.0

See Also:

Element.set(java.math.BigInteger)

newElement

E newElement(E e)

Returns a new element whose value is copied from the passed element.

Parameters:

e - the element whose value is copied.

Returns:

a new element whose value is copied from the passed element.

Since:

2.0.0

newElementFromHash

E newElementFromHash(byte[] source,
                   int offset,
                   int length)

Returns a new element whose value is set deterministically from the length bytes stored in the source parameter starting from the passed offset.

Parameters:

source - the buffer data.

offset - the starting offset.

length - the number of bytes to be used.

Returns:

this element modified.

Since:

2.0.0

newElementFromBytes

E newElementFromBytes(byte[] source)

Returns a new element whose value is set from the buffer source.

Parameters:

source - the source of bytes.

Returns:

the number of bytes read.

Since:

2.0.0

newElementFromBytes

E newElementFromBytes(byte[] source,
                    int offset)

Returns a new element whose value is set from the buffer source starting from offset.

Parameters:

source - the source of bytes.

offset - the starting offset.

Returns:

the number of bytes read.

Since:

2.0.0

newZeroElement

E newZeroElement()

Returns a new element whose value is zero.

Returns:

a new element whose value is zero.

Since:

1.0.0

newOneElement

E newOneElement()

Returns a new element whose value is one.

Returns:

a new element whose value is one.

Since:

1.0.0

newRandomElement

E newRandomElement()

Returns a new random element.

Returns:

a new random element.

Since:

1.0.0

getOrder

BigInteger getOrder()

Returns the order of this field.

Returns:

the order of this field. Returns 0 for infinite order.

Since:

1.0.0

isOrderOdd

boolean isOrderOdd()

Returns true> if the order is odd, false otherwise.

Returns:

true> if the order is odd, false otherwise.

Since:

1.2.0

getNqr

E getNqr()

Returns a quadratic non-residue in this field. It returns always the same element.

Returns:

a quadratic non-residue in this field.

Since:

1.0.0

getLengthInBytes

int getLengthInBytes()

Returns the length in bytes needed to represent an element of this Field.

Returns:

the length in bytes needed to represent an element of this Field.

Since:

1.0.0

getLengthInBytes

int getLengthInBytes(Element e)

Returns the length in bytes needed to represent an element of this Field.

Returns:

the length in bytes needed to represent an element of this Field.

Since:

1.0.0

getCanonicalRepresentationLengthInBytes

int getCanonicalRepresentationLengthInBytes()

Returns the length in bytes needed to canonical represent an element of this Field.

Returns:

the length in bytes needed to canonical represent an element of this Field.

Since:

2.0.0

twice

Element[] twice(Element[] elements)

Computes the component-wise twice.

Parameters:

elements - the vector of elements to be twiced.

Returns:

elements twiced.

Since:

1.1.0

add

Element[] add(Element[] a,
            Element[] b)

Computes the component-wise addition between a and b.

Parameters:

a - an array of elements of the field

b - another array of elements of the field to be added to a

Returns:

the vector a modified by adding b.

Since:

1.1.0

getElementPowPreProcessingFromBytes

ElementPowPreProcessing getElementPowPreProcessingFromBytes(byte[] source)

Reads an ElementPowPreProcessing from the buffer source.

Parameters:

source - the source of bytes.

Returns:

the ElementPowPreProcessing instance.

Since:

1.2.0

getElementPowPreProcessingFromBytes

ElementPowPreProcessing getElementPowPreProcessingFromBytes(byte[] source,
                                                          int offset)

Reads an ElementPowPreProcessing from the buffer source starting from offset.

Parameters:

source - the source of bytes.

offset - the starting offset.

Returns:

the ElementPowPreProcessing instance.

Since:

1.2.0