DocumentationClassesKNeighborsClassifier

Class: KNeighborsClassifier

Classifier implementing the k-nearest neighbors vote.

Read more in the User Guide.

Python Reference

Constructors

new KNeighborsClassifier()

new KNeighborsClassifier(opts?): KNeighborsClassifier

Parameters

ParameterTypeDescription
opts?object-
opts.algorithm?"auto" | "ball_tree" | "kd_tree" | "brute"Algorithm used to compute the nearest neighbors:
opts.leaf_size?numberLeaf size passed to BallTree or KDTree. This can affect the speed of the construction and query, as well as the memory required to store the tree. The optimal value depends on the nature of the problem.
opts.metric?stringMetric to use for distance computation. Default is “minkowski”, which results in the standard Euclidean distance when p = 2. See the documentation of scipy.spatial.distance and the metrics listed in distance_metrics for valid metric values. If metric is “precomputed”, X is assumed to be a distance matrix and must be square during fit. X may be a sparse graph, in which case only “nonzero” elements may be considered neighbors. If metric is a callable function, it takes two arrays representing 1D vectors as inputs and must return one value indicating the distance between those vectors. This works for Scipy’s metrics, but is less efficient than passing the metric name as a string.
opts.metric_params?anyAdditional keyword arguments for the metric function.
opts.n_jobs?numberThe number of parallel jobs to run for neighbors search. undefined means 1 unless in a joblib.parallel_backend context. \-1 means using all processors. See Glossary for more details. Doesn’t affect fit method.
opts.n_neighbors?numberNumber of neighbors to use by default for kneighbors queries.
opts.p?numberPower parameter for the Minkowski metric. When p = 1, this is equivalent to using manhattan_distance (l1), and euclidean_distance (l2) for p = 2. For arbitrary p, minkowski_distance (l_p) is used. This parameter is expected to be positive.
opts.weights?"uniform" | "distance"Weight function used in prediction. Possible values:

Returns KNeighborsClassifier

Defined in generated/neighbors/KNeighborsClassifier.ts:23

Properties

PropertyTypeDefault valueDefined in
_isDisposedbooleanfalsegenerated/neighbors/KNeighborsClassifier.ts:21
_isInitializedbooleanfalsegenerated/neighbors/KNeighborsClassifier.ts:20
_pyPythonBridgeundefinedgenerated/neighbors/KNeighborsClassifier.ts:19
idstringundefinedgenerated/neighbors/KNeighborsClassifier.ts:16
optsanyundefinedgenerated/neighbors/KNeighborsClassifier.ts:17

Accessors

classes_

Get Signature

get classes_(): Promise<any[]>

Class labels known to the classifier

Returns Promise<any[]>

Defined in generated/neighbors/KNeighborsClassifier.ts:488


effective_metric_

Get Signature

get effective_metric_(): Promise<string>

The distance metric used. It will be same as the metric parameter or a synonym of it, e.g. ‘euclidean’ if the metric parameter set to ‘minkowski’ and p parameter set to 2.

Returns Promise<string>

Defined in generated/neighbors/KNeighborsClassifier.ts:515


effective_metric_params_

Get Signature

get effective_metric_params_(): Promise<any>

Additional keyword arguments for the metric function. For most metrics will be same with metric_params parameter, but may also contain the p parameter value if the effective_metric_ attribute is set to ‘minkowski’.

Returns Promise<any>

Defined in generated/neighbors/KNeighborsClassifier.ts:542


feature_names_in_

Get Signature

get feature_names_in_(): Promise<ArrayLike>

Names of features seen during fit. Defined only when X has feature names that are all strings.

Returns Promise<ArrayLike>

Defined in generated/neighbors/KNeighborsClassifier.ts:596


n_features_in_

Get Signature

get n_features_in_(): Promise<number>

Number of features seen during fit.

Returns Promise<number>

Defined in generated/neighbors/KNeighborsClassifier.ts:569


n_samples_fit_

Get Signature

get n_samples_fit_(): Promise<number>

Number of samples in the fitted data.

Returns Promise<number>

Defined in generated/neighbors/KNeighborsClassifier.ts:623


outputs_2d_

Get Signature

get outputs_2d_(): Promise<boolean>

False when y’s shape is (n_samples, ) or (n_samples, 1) during fit otherwise true.

Returns Promise<boolean>

Defined in generated/neighbors/KNeighborsClassifier.ts:650


py

Get Signature

get py(): PythonBridge

Returns PythonBridge

Set Signature

set py(pythonBridge): void

Parameters

ParameterType
pythonBridgePythonBridge

Returns void

Defined in generated/neighbors/KNeighborsClassifier.ts:84

Methods

dispose()

dispose(): Promise<void>

Disposes of the underlying Python resources.

Once dispose() is called, the instance is no longer usable.

Returns Promise<void>

Defined in generated/neighbors/KNeighborsClassifier.ts:140


fit()

fit(opts): Promise<any>

Fit the k-nearest neighbors classifier from the training dataset.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeTraining data.
opts.y?anyTarget values.

Returns Promise<any>

Defined in generated/neighbors/KNeighborsClassifier.ts:157


get_metadata_routing()

get_metadata_routing(opts): Promise<any>

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

Parameters

ParameterTypeDescription
optsobject-
opts.routing?anyA MetadataRequest encapsulating routing information.

Returns Promise<any>

Defined in generated/neighbors/KNeighborsClassifier.ts:198


init()

init(py): Promise<void>

Initializes the underlying Python resources.

This instance is not usable until the Promise returned by init() resolves.

Parameters

ParameterType
pyPythonBridge

Returns Promise<void>

Defined in generated/neighbors/KNeighborsClassifier.ts:97


kneighbors()

kneighbors(opts): Promise<ArrayLike[]>

Find the K-neighbors of a point.

Returns indices of and distances to the neighbors of each point.

Parameters

ParameterTypeDescription
optsobject-
opts.n_neighbors?numberNumber of neighbors required for each sample. The default is the value passed to the constructor.
opts.return_distance?booleanWhether or not to return the distances.
opts.X?anyThe query point or points. If not provided, neighbors of each indexed point are returned. In this case, the query point is not considered its own neighbor.

Returns Promise<ArrayLike[]>

Defined in generated/neighbors/KNeighborsClassifier.ts:236


kneighbors_graph()

kneighbors_graph(opts): Promise<any[]>

Compute the (weighted) graph of k-Neighbors for points in X.

Parameters

ParameterTypeDescription
optsobject-
opts.mode?"connectivity" | "distance"Type of returned matrix: ‘connectivity’ will return the connectivity matrix with ones and zeros, in ‘distance’ the edges are distances between points, type of distance depends on the selected metric parameter in NearestNeighbors class.
opts.n_neighbors?numberNumber of neighbors for each sample. The default is the value passed to the constructor.
opts.X?anyThe query point or points. If not provided, neighbors of each indexed point are returned. In this case, the query point is not considered its own neighbor. For metric='precomputed' the shape should be (n_queries, n_indexed). Otherwise the shape should be (n_queries, n_features).

Returns Promise<any[]>

Defined in generated/neighbors/KNeighborsClassifier.ts:284


predict()

predict(opts): Promise<ArrayLike>

Predict the class labels for the provided data.

Parameters

ParameterTypeDescription
optsobject-
opts.X?anyTest samples.

Returns Promise<ArrayLike>

Defined in generated/neighbors/KNeighborsClassifier.ts:332


predict_proba()

predict_proba(opts): Promise<any>

Return probability estimates for the test data X.

Parameters

ParameterTypeDescription
optsobject-
opts.X?anyTest samples.

Returns Promise<any>

Defined in generated/neighbors/KNeighborsClassifier.ts:366


score()

score(opts): Promise<number>

Return the mean accuracy on the given test data and labels.

In multi-label classification, this is the subset accuracy which is a harsh metric since you require for each sample that each label set be correctly predicted.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights.
opts.X?ArrayLike[]Test samples.
opts.y?ArrayLikeTrue labels for X.

Returns Promise<number>

Defined in generated/neighbors/KNeighborsClassifier.ts:404


set_score_request()

set_score_request(opts): Promise<any>

Request metadata passed to the score method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in score.

Returns Promise<any>

Defined in generated/neighbors/KNeighborsClassifier.ts:452