Method prepare_query

nodedb-codec/src/vector_quant/opq.rs:305–319

Rotate the query, then build flat ADC distance table `[M × K]`.

(&self, q: &[f32])

    /// Rotate the query, then build flat ADC distance table `[M × K]`.
    fn prepare_query(&self, q: &[f32]) -> Self::Query {
        let rotated = self.apply_rotation(q);
        let mut table = vec![0.0f32; self.m * self.k];
        for s in 0..self.m {
            let offset = s * self.sub_dim;
            let sub_q = &rotated[offset..offset + self.sub_dim];
            for c in 0..self.k {
                table[s * self.k + c] = l2_sq(sub_q, &self.codebooks[s][c]);
            }
        }
        OpqQuery {
            distance_table: table,
            rotated,
        }
    }

    fn adc_lut(&self, q: &Self::Query) -> Option<AdcLut> {
        let mut lut = AdcLut::new(self.m as u16, self.k as u16);