Trait snarkvm_wasm::FftParameters
source · pub trait FftParameters: 'static + Send + Sync + Sized {
type BigInteger: BigInteger;
const TWO_ADICITY: u32;
const TWO_ADIC_ROOT_OF_UNITY: Self::BigInteger;
const POWERS_OF_ROOTS_OF_UNITY: &'static [Self::BigInteger];
const SMALL_SUBGROUP_BASE: Option<u32> = None;
const SMALL_SUBGROUP_BASE_ADICITY: Option<u32> = None;
const LARGE_SUBGROUP_ROOT_OF_UNITY: Option<Self::BigInteger> = None;
}Expand description
A trait that defines parameters for a field that can be used for FFTs.
Required Associated Types§
type BigInteger: BigInteger
Required Associated Constants§
sourceconst TWO_ADICITY: u32
const TWO_ADICITY: u32
Let N be the size of the multiplicative group defined by the field.
Then TWO_ADICITY is the two-adicity of N, i.e. the integer s
such that N = 2^s * t for some odd integer t.
2^s * t = MODULUS - 1 with t odd. This is the two-adicity of the prime.
sourceconst TWO_ADIC_ROOT_OF_UNITY: Self::BigInteger
const TWO_ADIC_ROOT_OF_UNITY: Self::BigInteger
2^s root of unity, defined as GENERATOR^t.
sourceconst POWERS_OF_ROOTS_OF_UNITY: &'static [Self::BigInteger]
const POWERS_OF_ROOTS_OF_UNITY: &'static [Self::BigInteger]
TWO_ADIC_ROOT_OF_UNITY^2^i for i := 0..TWO_ADICITY-1
Provided Associated Constants§
sourceconst SMALL_SUBGROUP_BASE: Option<u32> = None
const SMALL_SUBGROUP_BASE: Option<u32> = None
An integer b such that there exists a multiplicative subgroup
of size b^k for some integer k.
sourceconst SMALL_SUBGROUP_BASE_ADICITY: Option<u32> = None
const SMALL_SUBGROUP_BASE_ADICITY: Option<u32> = None
The integer k such that there exists a multiplicative subgroup
of size Self::SMALL_SUBGROUP_BASE^k.
sourceconst LARGE_SUBGROUP_ROOT_OF_UNITY: Option<Self::BigInteger> = None
const LARGE_SUBGROUP_ROOT_OF_UNITY: Option<Self::BigInteger> = None
GENERATOR^((MODULUS-1) / (2^s * SMALL_SUBGROUP_BASE^SMALL_SUBGROUP_BASE_ADICITY)) Used for mixed-radix FFT.