Struct NormalizedSubspacePolys 

pub struct NormalizedSubspacePolys<F> { /* private fields */ }

Constants for evaluating the normalized subspace polynomials at an arbitrary field point.

Built from a DomainContext, so these match the basis its NTT transforms over.

Holds only what the recurrence needs. The evaluations on the basis elements stay in the DomainContext. Keeping them there is what stops them drifting out of step with the NTT’s own twiddles.

Implementations

impl<F: BinaryField> NormalizedSubspacePolys<F>

pub fn new<DC: DomainContext<Field = F>>(domain_context: &DC) -> Self

Builds the constants for domain_context’s basis.

Panics

Panics if domain_context.log_domain_size() is zero. Panics if the basis is linearly dependent, which makes a normalizer vanish.

pub const fn log_domain_size(&self) -> usize

The number of polynomials, matching the domain context’s log_domain_size.

pub fn evals_at(&self, x: F) -> Vec<F>

Evaluates every $\hat{W}_k$ at an arbitrary field point, in increasing $k$.

Runs the normalized recurrence

    W_hat_0(x)     = x * beta_0^-1
    W_hat_{i+1}(x) = W_hat_i(x) * (W_hat_i(x) + 1) * step_inv[i]

It follows from $W_{i+1}(X) = W_i(X) (W_i(X) + W_i(\beta_i))$, divided by the normalizers.

Costs $\ell$ multiplications and no inversions.

Trait Implementations

impl<F: Clone> Clone for NormalizedSubspacePolys<F>

fn clone(&self) -> NormalizedSubspacePolys<F>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<F: Debug> Debug for NormalizedSubspacePolys<F>

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

Formats the value using the given formatter.