Struct Turbo4Codec 

pub struct Turbo4Codec { /* private fields */ }

The Turbo4 codec for a fixed (dimension, rotation-seed) pair.

Implementations

impl Turbo4Codec

pub fn new(dim: usize, rotation_seed: u64) -> Result<Self, TurboQuantError>

Build a codec. dim must be even and ≥ 2 (all practical embedding widths are; evenness keeps the two-run nibble layout exact).

pub fn dim(&self) -> usize

pub fn code_len(&self) -> usize

Stored bytes per vector: D/2 nibbles + 8 bytes of constants.

pub fn query_len(&self) -> usize

Query blob length: D int8 codes + 8 bytes of constants.

pub fn encode(&self, v: &[f32]) -> Result<Vec<u8>, TurboQuantError>

Encode a vector into its Turbo4 code blob.

pub fn encode_dual( &self, v: &[f32], ) -> Result<(Vec<u8>, Vec<u8>), TurboQuantError>

Encode both planes from one rotation pass: the Turbo4 code and the 1-bit candidate-generation code (ADR-297 phase C). The bits blob shares this codec’s rotation, so a single query prep serves both.

pub fn encode_query(&self, q: &[f32]) -> Result<Turbo4Query, TurboQuantError>

Prepare a query for traversal + rescoring.

pub fn decode_rotated(&self, blob: &[u8]) -> Vec<f32>

Reconstruct the rotated-space approximation from a code blob (tests/debugging only — the search path never reconstructs).

pub fn decode(&self, blob: &[u8]) -> Vec<f32>

Reconstruct the original-space approximation (inverse rotation applied).