GF2nPolynomial (Bouncy Castle Library 1.57 API Specification)

java.lang.Object
- org.bouncycastle.pqc.math.linearalgebra.GF2nPolynomial

```
public class GF2nPolynomial
extends java.lang.Object
```
This class implements polynomials over GF2nElements.

See Also:
GF2nElement

Constructor Summary

Constructors
Constructor and Description
`GF2nPolynomial(GF2nPolynomial a)` Creates a new PolynomialGF2n by cloning the given PolynomialGF2n a.
`GF2nPolynomial(GF2Polynomial polynomial, GF2nField B1)` Creates a new PolynomialGF2n from the given Bitstring polynomial over the GF2nField B1.
`GF2nPolynomial(int deg, GF2nElement elem)` Creates a new PolynomialGF2n of size deg and elem as coefficients.

Method Summary

Methods
Modifier and Type	Method and Description
`GF2nPolynomial`	`add(GF2nPolynomial b)` Adds the PolynomialGF2n `b` to `this` and returns the result in a new `PolynomialGF2n`.
`void`	`assignZeroToElements()`
`GF2nElement`	`at(int index)` Returns the coefficient at index.
`GF2nPolynomial[]`	`divide(GF2nPolynomial b)` Divides this by b and stores the result in a new PolynomialGF2n[2], quotient in result[0] and remainder in result[1].
`void`	`enlarge(int k)` Enlarges the size of this PolynomialGF2n to k + 1.
`boolean`	`equals(java.lang.Object other)`
`GF2nPolynomial`	`gcd(GF2nPolynomial g)` Computes the greatest common divisor of this and g and returns the result in a new PolynomialGF2n.
`int`	`getDegree()` Returns the degree of this PolynomialGF2n.
`int`	`hashCode()`
`boolean`	`isZero()` Returns true if all coefficients equal zero.
`GF2nPolynomial`	`multiply(GF2nPolynomial b)` Multiplies this by b and returns the result in a new PolynomialGF2n.
`GF2nPolynomial`	`multiplyAndReduce(GF2nPolynomial b, GF2nPolynomial g)` Multiplies this by b, reduces the result by g and returns it in a new PolynomialGF2n.
`GF2nPolynomial`	`quotient(GF2nPolynomial b)` Divides this by b and stores the quotient in a new PolynomialGF2n.
`GF2nPolynomial`	`reduce(GF2nPolynomial g)` Reduces this by g and returns the result in a new PolynomialGF2n.
`GF2nPolynomial`	`remainder(GF2nPolynomial b)` Divides this by b and stores the remainder in a new PolynomialGF2n.
`GF2nPolynomial`	`scalarMultiply(GF2nElement s)` Multiplies the scalar s to each coefficient of this PolynomialGF2n and returns the result in a new PolynomialGF2n.
`void`	`set(int index, GF2nElement elem)` Sets the coefficient at index to elem.
`GF2nPolynomial`	`shiftLeft(int amount)`
`void`	`shiftThisLeft(int amount)` Shifts left this by amount and stores the result in this PolynomialGF2n.
`void`	`shrink()`
`int`	`size()` Returns the size (=maximum degree + 1) of this PolynomialGF2n.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - GF2nPolynomial
```
public GF2nPolynomial(int deg,
              GF2nElement elem)
```
    Creates a new PolynomialGF2n of size deg and elem as coefficients.
    
    Parameters:
    deg - - the maximum degree + 1
    elem - - a GF2nElement
  - GF2nPolynomial
```
public GF2nPolynomial(GF2nPolynomial a)
```
    Creates a new PolynomialGF2n by cloning the given PolynomialGF2n a.
    
    Parameters:
    a - the PolynomialGF2n to clone
  - GF2nPolynomial
```
public GF2nPolynomial(GF2Polynomial polynomial,
              GF2nField B1)
```
    Creates a new PolynomialGF2n from the given Bitstring polynomial over the GF2nField B1.
    
    Parameters:
    polynomial - the Bitstring to use
    B1 - the field
- Method Detail
  - assignZeroToElements
```
public final void assignZeroToElements()
```
  - size
```
public final int size()
```
    Returns the size (=maximum degree + 1) of this PolynomialGF2n. This is not the degree, use getDegree instead.
    
    Returns:
    the size (=maximum degree + 1) of this PolynomialGF2n.
  - getDegree
```
public final int getDegree()
```
    Returns the degree of this PolynomialGF2n.
    
    Returns:
    the degree of this PolynomialGF2n.
  - enlarge
```
public final void enlarge(int k)
```
    Enlarges the size of this PolynomialGF2n to k + 1.
    
    Parameters:
    k - the new maximum degree
  - shrink
```
public final void shrink()
```
  - set
```
public final void set(int index,
       GF2nElement elem)
```
    Sets the coefficient at index to elem.
    
    Parameters:
    index - the index
    elem - the GF2nElement to store as coefficient index
  - at
```
public final GF2nElement at(int index)
```
    Returns the coefficient at index.
    
    Parameters:
    index - the index
    
    Returns:
    the GF2nElement stored as coefficient index
  - isZero
```
public final boolean isZero()
```
    Returns true if all coefficients equal zero.
    
    Returns:
    true if all coefficients equal zero.
  - equals
```
public final boolean equals(java.lang.Object other)
```
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
    
    Returns:
    the hash code of this polynomial
  - add
```
public final GF2nPolynomial add(GF2nPolynomial b)
                         throws java.lang.RuntimeException
```
    Adds the PolynomialGF2n b to this and returns the result in a new PolynomialGF2n.
    
    Parameters:
    b - - the PolynomialGF2n to add
    
    Returns:
    this + b
    
    Throws:
    
    DifferentFieldsException - if this and b are not defined over the same field.
    
    java.lang.RuntimeException
  - scalarMultiply
```
public final GF2nPolynomial scalarMultiply(GF2nElement s)
                                    throws java.lang.RuntimeException
```
    Multiplies the scalar s to each coefficient of this PolynomialGF2n and returns the result in a new PolynomialGF2n.
    
    Parameters:
    s - the scalar to multiply
    
    Returns:
    this x s
    
    Throws:
    
    DifferentFieldsException - if this and s are not defined over the same field.
    
    java.lang.RuntimeException
  - multiply
```
public final GF2nPolynomial multiply(GF2nPolynomial b)
                              throws java.lang.RuntimeException
```
    Multiplies this by b and returns the result in a new PolynomialGF2n.
    
    Parameters:
    b - the PolynomialGF2n to multiply
    
    Returns:
    this * b
    
    Throws:
    
    DifferentFieldsException - if this and b are not defined over the same field.
    
    java.lang.RuntimeException
  - multiplyAndReduce
```
public final GF2nPolynomial multiplyAndReduce(GF2nPolynomial b,
                               GF2nPolynomial g)
                                       throws java.lang.RuntimeException,
                                              java.lang.ArithmeticException
```
    Multiplies this by b, reduces the result by g and returns it in a new PolynomialGF2n.
    
    Parameters:
    b - the PolynomialGF2n to multiply
    g - the modul
    
    Returns:
    this * b mod g
    
    Throws:
    
    DifferentFieldsException - if this, b and g are not all defined over the same field.
    
    java.lang.RuntimeException
    
    java.lang.ArithmeticException
  - reduce
```
public final GF2nPolynomial reduce(GF2nPolynomial g)
                            throws java.lang.RuntimeException,
                                   java.lang.ArithmeticException
```
    Reduces this by g and returns the result in a new PolynomialGF2n.
    
    Parameters:
    g - - the modulus
    
    Returns:
    this % g
    
    Throws:
    
    DifferentFieldsException - if this and g are not defined over the same field.
    
    java.lang.RuntimeException
    
    java.lang.ArithmeticException
  - shiftThisLeft
```
public final void shiftThisLeft(int amount)
```
    Shifts left this by amount and stores the result in this PolynomialGF2n.
    
    Parameters:
    amount - the amount to shift the coefficients
  - shiftLeft
```
public final GF2nPolynomial shiftLeft(int amount)
```
  - divide
```
public final GF2nPolynomial[] divide(GF2nPolynomial b)
                              throws java.lang.RuntimeException,
                                     java.lang.ArithmeticException
```
    Divides this by b and stores the result in a new PolynomialGF2n[2], quotient in result[0] and remainder in result[1].
    
    Parameters:
    b - the divisor
    
    Returns:
    the quotient and remainder of this / b
    
    Throws:
    
    DifferentFieldsException - if this and b are not defined over the same field.
    
    java.lang.RuntimeException
    
    java.lang.ArithmeticException
  - remainder
```
public final GF2nPolynomial remainder(GF2nPolynomial b)
                               throws java.lang.RuntimeException,
                                      java.lang.ArithmeticException
```
    Divides this by b and stores the remainder in a new PolynomialGF2n.
    
    Parameters:
    b - the divisor
    
    Returns:
    the remainder this % b
    
    Throws:
    
    DifferentFieldsException - if this and b are not defined over the same field.
    
    java.lang.RuntimeException
    
    java.lang.ArithmeticException
  - quotient
```
public final GF2nPolynomial quotient(GF2nPolynomial b)
                              throws java.lang.RuntimeException,
                                     java.lang.ArithmeticException
```
    Divides this by b and stores the quotient in a new PolynomialGF2n.
    
    Parameters:
    b - the divisor
    
    Returns:
    the quotient this / b
    
    Throws:
    
    DifferentFieldsException - if this and b are not defined over the same field.
    
    java.lang.RuntimeException
    
    java.lang.ArithmeticException
  - gcd
```
public final GF2nPolynomial gcd(GF2nPolynomial g)
                         throws java.lang.RuntimeException,
                                java.lang.ArithmeticException
```
    Computes the greatest common divisor of this and g and returns the result in a new PolynomialGF2n.
    
    Parameters:
    g - - a GF2nPolynomial
    
    Returns:
    gcd(this, g)
    
    Throws:
    
    DifferentFieldsException - if the coefficients of this and g use different fields
    
    java.lang.ArithmeticException - if coefficients are zero.
    
    java.lang.RuntimeException

Class GF2nPolynomial

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

GF2nPolynomial

GF2nPolynomial

GF2nPolynomial

Method Detail

assignZeroToElements

size

getDegree

enlarge

shrink

set

at

isZero

equals

hashCode

add

scalarMultiply

multiply

multiplyAndReduce

reduce

shiftThisLeft

shiftLeft

divide

remainder

quotient

gcd