Struct ark_ed_on_bls12_381::EdwardsParameters

pub struct EdwardsParameters;

JubJub is a twisted Edwards curve. These curves have equations of the form: ax² + y² = 1 - dx²y². over some base finite field Fq.

JubJub’s curve equation: -x² + y² = 1 - (10240/10241)x²y²

q = 52435875175126190479447740508185965837690552500527637822603658699938581184513.

a = -1. d = (10240/10241) mod q = 19257038036680949359750312669786877991949435402254120286184196891950884077233.

Sage script to calculate these:

q = 52435875175126190479447740508185965837690552500527637822603658699938581184513
Fq = GF(q)
d = -(Fq(10240)/Fq(10241))

These parameters and the sage script obtained from: https://github.com/zcash/zcash/issues/2230#issuecomment-317182190

Trait Implementations

impl Clone for EdwardsParameters

fn clone(&self) -> EdwardsParameters

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Default for EdwardsParameters

fn default() -> EdwardsParameters

Returns the “default value” for a type.

impl ModelParameters for EdwardsParameters

type BaseField = Fq

type ScalarField = Fr

impl MontgomeryModelParameters for EdwardsParameters

const COEFF_A: Fq

COEFF_A = 40962

const COEFF_B: Fq

COEFF_B = -40964

type TEModelParameters = EdwardsParameters

impl PartialEq<EdwardsParameters> for EdwardsParameters

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

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

#[must_use]

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

This method tests for !=.

impl TEModelParameters for EdwardsParameters

const COEFF_A: Fq

COEFF_A = -1

const COEFF_D: Fq

COEFF_D = (10240/10241) mod q

const COFACTOR: &'static [u64]

COFACTOR = 8

const COFACTOR_INV: Fr

COFACTOR^(-1) mod r = 819310549611346726241370945440405716213240158234039660170669895299022906775

const AFFINE_GENERATOR_COEFFS: (Self::BaseField, Self::BaseField)

AFFINE_GENERATOR_COEFFS = (GENERATOR_X, GENERATOR_Y)

fn mul_by_a(elem: &Self::BaseField) -> Self::BaseField

Multiplication by a is simply negation here.

type MontgomeryModelParameters = EdwardsParameters

impl Eq for EdwardsParameters

impl StructuralEq for EdwardsParameters

impl StructuralPartialEq for EdwardsParameters