Struct PQScratch 

pub struct PQScratch {
    pub aligned_pqtable_dist_scratch: Poly<[f32], AlignedAllocator>,
    pub aligned_dist_scratch: Poly<[f32], AlignedAllocator>,
    pub aligned_pq_coord_scratch: Poly<[u8], AlignedAllocator>,
    pub query_scratch: Vec<f32>,
}

PQ scratch

Fields

aligned_pqtable_dist_scratch: Poly<[f32], AlignedAllocator>

Aligned pq table distance scratch, the length must be at least [256 * NCHUNKS]. 256 is the number of PQ centroids. This is used to store the distance between each chunk in the query vector to each centroid, which is why the length is num of centroids * num of chunks

aligned_dist_scratch: Poly<[f32], AlignedAllocator>

Aligned dist scratch, must be at least diskann MAX_DEGREE This is used to temporarily save the pq distance between query vector to the candidate vectors.

aligned_pq_coord_scratch: Poly<[u8], AlignedAllocator>

Aligned pq coord scratch, must be at least [N_CHUNKS * MAX_DEGREE] This is used to store the pq coordinates of the candidate vectors.

query_scratch: Vec<f32>

Query scratch buffer stored as f32, sized by the PQ table’s logical dimension. set populates it from a caller-provided &[f32]; PQTable::preprocess_query can then rotate or otherwise preprocess it.

Implementations

impl PQScratch

pub fn new( graph_degree: usize, dim: usize, num_pq_chunks: usize, num_centers: usize, ) -> ANNResult<Self>

Create a new pq scratch.

dim is the PQ table’s logical dimension (PQData::get_dim()); the internal query_scratch buffer is sized to exactly this many f32 slots.

pub fn set(&mut self, query: &[f32]) -> ANNResult<()>

Copy the first dim elements of query into query_scratch.

query must already be in full-precision f32 representation; quantized inputs (e.g. MinMaxElement) should be decoded via VectorRepr::as_f32 at the caller boundary before invoking this method.

Accepts oversized query (only the first dim elements are used) for backwards compatibility with callers that hold alignment-padded buffers. Returns DimensionMismatchError if query.len() < query_scratch.len().

Trait Implementations

impl Debug for PQScratch

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

Formats the value using the given formatter.