Struct IndexParams

pub struct IndexParams(pub cuvsIvfPqIndexParams_t);

Tuple Fields

0: cuvsIvfPqIndexParams_t

Implementations

impl IndexParams

pub fn new() -> Result<IndexParams>

Returns a new IndexParams

pub fn set_n_lists(self, n_lists: u32) -> IndexParams

The number of clusters used in the coarse quantizer.

pub fn set_metric(self, metric: DistanceType) -> IndexParams

DistanceType to use for building the index

pub fn set_metric_arg(self, metric_arg: f32) -> IndexParams

The number of iterations searching for kmeans centers during index building.

pub fn set_kmeans_n_iters(self, kmeans_n_iters: u32) -> IndexParams

The number of iterations searching for kmeans centers during index building.

pub fn set_kmeans_trainset_fraction( self, kmeans_trainset_fraction: f64, ) -> IndexParams

If kmeans_trainset_fraction is less than 1, then the dataset is subsampled, and only n_samples * kmeans_trainset_fraction rows are used for training.

pub fn set_pq_bits(self, pq_bits: u32) -> IndexParams

The bit length of the vector element after quantization.

pub fn set_pq_dim(self, pq_dim: u32) -> IndexParams

The dimensionality of a the vector after product quantization. When zero, an optimal value is selected using a heuristic. Note pq_dim * pq_bits must be a multiple of 8. Hint: a smaller ‘pq_dim’ results in a smaller index size and better search performance, but lower recall. If ‘pq_bits’ is 8, ‘pq_dim’ can be set to any number, but multiple of 8 are desirable for good performance. If ‘pq_bits’ is not 8, ‘pq_dim’ should be a multiple of 8. For good performance, it is desirable that ‘pq_dim’ is a multiple of 32. Ideally, ‘pq_dim’ should be also a divisor of the dataset dim.

pub fn set_codebook_kind(self, codebook_kind: codebook_gen) -> IndexParams

pub fn set_force_random_rotation( self, force_random_rotation: bool, ) -> IndexParams

Apply a random rotation matrix on the input data and queries even if dim % pq_dim == 0. Note: if dim is not multiple of pq_dim, a random rotation is always applied to the input data and queries to transform the working space from dim to rot_dim, which may be slightly larger than the original space and and is a multiple of pq_dim (rot_dim % pq_dim == 0). However, this transform is not necessary when dim is multiple of pq_dim (dim == rot_dim, hence no need in adding “extra” data columns / features). By default, if dim == rot_dim, the rotation transform is initialized with the identity matrix. When force_random_rotation == True, a random orthogonal transform

pub fn set_max_train_points_per_pq_code(self, max_pq_points: u32) -> IndexParams

The max number of data points to use per PQ code during PQ codebook training. Using more data points per PQ code may increase the quality of PQ codebook but may also increase the build time. The parameter is applied to both PQ codebook generation methods, i.e., PER_SUBSPACE and PER_CLUSTER. In both cases, we will use pq_book_size * max_train_points_per_pq_code training points to train each codebook.

pub fn set_add_data_on_build(self, add_data_on_build: bool) -> IndexParams

After training the coarse and fine quantizers, we will populate the index with the dataset if add_data_on_build == true, otherwise the index is left empty, and the extend method can be used to add new vectors to the index.

Trait Implementations

impl Debug for IndexParams

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

Formats the value using the given formatter.

impl Drop for IndexParams

fn drop(&mut self)

Executes the destructor for this type.