Struct scuttlebutt::field::polynomial::Polynomial

pub struct Polynomial<FE: FiniteField> {
    pub constant: FE,
    pub coefficients: SmallVec<[FE; 3]>,
}

A polynomial over some given finite field, represented as the coefficient vector.

Fields

constant: FE

The coefficient for $x^0$

coefficients: SmallVec<[FE; 3]>

The coefficients for $x^1, ..., x^n$

coefficients[i] is the coefficient for $x^{i+1}$

Implementations

impl<FE: FiniteField> Polynomial<FE>

pub fn random(rng: &mut (impl RngCore + ?Sized), degree: usize) -> Self

Construct a random polynomial of the given degree.

pub fn zero() -> Self

Return the zero polynomial.

pub fn one() -> Self

Return the polynomial P(x) = 1

pub fn constant(c: FE) -> Self

Return the polynomial P(x) = c

pub fn x() -> Self

Return the polynomial P(x) = x

pub fn degree(&self) -> usize

Return the degree of the polynomial

pub fn eval(&self, at: FE) -> FE

Evaluate the polynomial at a given x value.

pub fn divmod(&self, divisor: &Self) -> (Self, Self)

Return (self / divisor, self % divisor)

pub fn interpolate(points: &[(FE, FE)]) -> Self

Interpolate a polynomial from the given (x,y) points

Panics

This function will panic if points is empty, or if any x values collide.

Trait Implementations

impl<'a, FE: FiniteField> AddAssign<&'a Polynomial<FE>> for Polynomial<FE>

fn add_assign(&mut self, rhs: &'a Polynomial<FE>)

Performs the += operation.

impl<FE: Clone + FiniteField> Clone for Polynomial<FE>

fn clone(&self) -> Polynomial<FE>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<FE: FiniteField> ConstantTimeEq for Polynomial<FE>

fn ct_eq(&self, other: &Self) -> Choice

Determine if two items are equal.

fn ct_ne(&self, other: &Self) -> Choice

Determine if two items are NOT equal.

impl<FE: FiniteField> Debug for Polynomial<FE>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<FE: FiniteField> From<&[FE]> for Polynomial<FE>

fn from(v: &[FE]) -> Self

Converts to this type from the input type.

impl<FE: FiniteField> Index<usize> for Polynomial<FE>

Index into the Polynomial where 0 is the constant term.

type Output = FE

The returned type after indexing.

fn index(&self, index: usize) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<FE: FiniteField> IndexMut<usize> for Polynomial<FE>

Index into the Polynomial where 0 is the constant term.

fn index_mut(&mut self, index: usize) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl<'a, FE: FiniteField> MulAssign<&'a Polynomial<FE>> for Polynomial<FE>

fn mul_assign(&mut self, rhs: &'a Polynomial<FE>)

Performs the *= operation.

impl<FE: FiniteField> MulAssign<FE> for Polynomial<FE>

fn mul_assign(&mut self, rhs: FE)

Performs the *= operation.

impl<FE: FiniteField> PartialEq for Polynomial<FE>

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<'a, FE: FiniteField> SubAssign<&'a Polynomial<FE>> for Polynomial<FE>

fn sub_assign(&mut self, rhs: &'a Polynomial<FE>)

Performs the -= operation.

impl<FE: Eq + FiniteField> Eq for Polynomial<FE>