Neighbors and vector search

Exact neighbors, IVF, CAGRA and quantized indexes for vector search.

AdditiveChi2Sampler	Approximate feature map for the additive chi-squared kernel.
CagraIndex	Graph-based approximate nearest-neighbor index (CAGRA).
connected_components	Connected components of a graph.
IVFIndex	Approximate nearest-neighbor index with inverted lists (IVF-Flat).
IVFPQIndex	Approximate nearest-neighbor index with inverted lists and product quantization (IVF-PQ).
IVFRaBitQIndex	Approximate nearest-neighbor index with inverted lists and 1-bit RaBitQ codes (IVF-RaBitQ).
IVFSQIndex	Approximate nearest-neighbor index with inverted lists and 8-bit scalar quantization (IVF-SQ).
KernelPCA	Kernel principal component analysis.
KNeighborsClassifier	Classifier that votes among the k nearest training points.
KNeighborsRegressor	Regressor that averages the targets of the k nearest training points.
KNNImputer	Imputation of missing values by k nearest neighbors.
LabelPropagation	Semi-supervised classification by label propagation.
LabelSpreading	Semi-supervised classification by label spreading.
LocalOutlierFactor	Unsupervised outlier detection by the local outlier factor (LOF).
Louvain	Louvain community detection on an undirected weighted graph.
NearestCentroid	Nearest centroid classifier.
NearestNeighbors	Exact k-nearest-neighbor search.
OneClassSVM	Unsupervised outlier detection with the nu one-class SVM.
PageRank	PageRank scores of a directed graph by power iteration.
PolynomialCountSketch	Polynomial kernel approximation by tensor sketch.
RadiusNeighbors	Find every fitted point within a radius of each query.
refine	Re-rank candidate neighbors by exact distance.
SkewedChi2Sampler	Approximate feature map for the skewed chi-squared kernel.
SVGP	Sparse variational Gaussian process regression with inducing points.
TSNE	t-distributed Stochastic Neighbor Embedding (t-SNE) into two dimensions.