Struct HnswIndex 

pub struct HnswIndex { /* private fields */ }

HNSW Index for approximate nearest neighbor search

Implementations

impl HnswIndex

pub fn new(dimension: usize, config: HnswConfig) -> HnswIndex

Create a new empty HNSW index

pub fn with_dimension(dimension: usize) -> HnswIndex

Create with default configuration

pub fn len(&self) -> usize

Get the number of vectors in the index

pub fn is_empty(&self) -> bool

Check if the index is empty

pub fn get_vector(&self, id: u64) -> Option<&[f32]>

Get the vector for a node ID

pub fn insert(&mut self, vector: Vec<f32>) -> u64

Insert a vector and return its assigned ID

pub fn insert_with_id(&mut self, id: u64, vector: Vec<f32>)

Insert a vector with a specific ID

pub fn search(&self, query: &[f32], k: usize) -> Vec<DistanceResult>

Search for k nearest neighbors

pub fn search_with_ef( &self, query: &[f32], k: usize, ef: usize, ) -> Vec<DistanceResult>

Search with custom ef parameter

pub fn search_filtered( &self, query: &[f32], k: usize, filter: &HashSet<u64>, ) -> Vec<DistanceResult>

Search with a filter (bitset of allowed IDs)

pub fn search_filtered_with_ef( &self, query: &[f32], k: usize, filter: &HashSet<u64>, ef: usize, ) -> Vec<DistanceResult>

Search with filter and custom ef

pub fn insert_batch(&mut self, vectors: Vec<Vec<f32>>) -> Vec<u64>

Insert multiple vectors at once

More efficient than individual inserts for large batches

pub fn insert_batch_with_ids(&mut self, items: Vec<(u64, Vec<f32>)>)

Insert multiple vectors with specific IDs

pub fn delete(&mut self, id: u64) -> bool

Remove a node from the index

Note: This is a “soft” delete - the node is marked as deleted and excluded from search results, but connections are not fully repaired. For better performance after many deletes, rebuild the index.

pub fn contains(&self, id: u64) -> bool

Check if a node exists

pub fn search_adaptive(&self, query: &[f32], k: usize) -> Vec<DistanceResult>

Search with adaptive ef based on index size

Automatically adjusts ef_search based on the number of results needed and the size of the index for better accuracy/speed tradeoff.

pub fn stats(&self) -> HnswStats

Get statistics about the index

pub fn to_bytes(&self) -> Vec<u8>

Serialize the index to bytes for storage

pub fn from_bytes(bytes: &[u8]) -> Result<HnswIndex, String>

Deserialize index from bytes