Struct OPQIndex 

pub struct OPQIndex {
    pub config: OPQConfig,
    pub rotation: RotationMatrix,
    pub codebooks: Vec<Vec<Vec<f32>>>,
    pub dimensions: usize,
}

OPQ index: learns rotation R + PQ codebooks, supports ADC search.

Fields

config: OPQConfig

rotation: RotationMatrix

codebooks: Vec<Vec<Vec<f32>>>

Codebooks: [subspace][centroid][subspace_dim].

dimensions: usize

Implementations

impl OPQIndex

pub fn train(vectors: &[Vec<f32>], config: OPQConfig) -> Result<Self>

Train OPQ via alternating rotation update and PQ codebook learning.

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

Encode a vector: rotate then PQ-quantize.

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

Decode PQ codes back to approximate vector (with inverse rotation).

pub fn search_adc( &self, query: &[f32], codes_db: &[Vec<u8>], top_k: usize, ) -> Result<Vec<(usize, f32)>>

ADC search: precompute distance tables then sum lookups per database vector.

pub fn quantization_error(&self, vectors: &[Vec<f32>]) -> Result<f32>

Mean squared quantization error over a set of vectors.

Trait Implementations

impl Clone for OPQIndex

fn clone(&self) -> OPQIndex

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OPQIndex

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for OPQIndex

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for OPQIndex

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.