skhubness.neighbors.HNSW¶
-
class
skhubness.neighbors.
HNSW
(n_candidates: int = 5, metric: str = 'euclidean', method: str = 'hnsw', post_processing: int = 2, n_jobs: int = 1, verbose: int = 0)[source]¶ Wrapper for using nmslib
Hierarchical navigable small-world graphs are data structures, that allow for approximate nearest neighbor search. Here, an implementation from nmslib is used.
- Parameters
- n_candidates: int, default = 5
Number of neighbors to retrieve
- metric: str, default = ‘euclidean’
Distance metric, allowed are “angular”, “euclidean”, “manhattan”, “hamming”, “dot”
- method: str, default = ‘hnsw’,
ANN method to use. Currently, only ‘hnsw’ is supported.
- post_processing: int, default = 2
More post processing means longer index creation, and higher retrieval accuracy.
- n_jobs: int, default = 1
Number of parallel jobs
- verbose: int, default = 0
Verbosity level. If verbose >= 2, show progress bar on indexing.
- Attributes
- valid_metrics:
List of valid distance metrics/measures
-
__init__
(self, n_candidates: 'int' = 5, metric: 'str' = 'euclidean', method: 'str' = 'hnsw', post_processing: 'int' = 2, n_jobs: 'int' = 1, verbose: 'int' = 0)[source]¶ Initialize self. See help(type(self)) for accurate signature.
Methods
__init__
(self, n_candidates, metric, method, …)Initialize self.
fit
(self, X[, y])Setup the HNSW index from training data.
kneighbors
(self, X, n_candidates, …)Retrieve k nearest neighbors.
Attributes
valid_metrics
-
fit
(self, X, y=None) → 'HNSW'[source]¶ Setup the HNSW index from training data.
- Parameters
- X: np.array
Data to be indexed
- y: any
Ignored
- Returns
- self: HNSW
An instance of HNSW with a built graph
-
kneighbors
(self, X: 'np.ndarray' = None, n_candidates: 'int' = None, return_distance: 'bool' = True) → 'Union[Tuple[np.array, np.array], np.array]'[source]¶ Retrieve k nearest neighbors.
- Parameters
- X: np.array or None, optional, default = None
Query objects. If None, search among the indexed objects.
- n_candidates: int or None, optional, default = None
Number of neighbors to retrieve. If None, use the value passed during construction.
- return_distance: bool, default = True
If return_distance, will return distances and indices to neighbors. Else, only return the indices.