KNeighborsClassifier
Classifier implementing the k-nearest neighbors vote.
Read more in the User Guide.
Python Reference (opens in a new tab)
Constructors
constructor()
Signature
new KNeighborsClassifier(opts?: object): KNeighborsClassifier;Parameters
| Name | Type | Description |
|---|---|---|
opts? | object | - |
opts.algorithm? | "auto" | "ball_tree" | "kd_tree" | "brute" | Algorithm used to compute the nearest neighbors: Default Value 'auto' |
opts.leaf_size? | number | Leaf 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. Default Value 30 |
opts.metric? | string | Metric 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 (opens in a new tab) 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. Default Value 'minkowski' |
opts.metric_params? | any | Additional keyword arguments for the metric function. |
opts.n_jobs? | number | The number of parallel jobs to run for neighbors search. undefined means 1 unless in a joblib.parallel\_backend (opens in a new tab) context. \-1 means using all processors. See Glossary for more details. Doesn’t affect fit method. |
opts.n_neighbors? | number | Number of neighbors to use by default for kneighbors queries. Default Value 5 |
opts.p? | number | Power 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. Default Value 2 |
opts.weights? | "uniform" | "distance" | Weight function used in prediction. Possible values: Default Value 'uniform' |
Returns
Defined in: generated/neighbors/KNeighborsClassifier.ts:23 (opens in a new tab)
Properties
_isDisposed
boolean=false
Defined in: generated/neighbors/KNeighborsClassifier.ts:21 (opens in a new tab)
_isInitialized
boolean=false
Defined in: generated/neighbors/KNeighborsClassifier.ts:20 (opens in a new tab)
_py
PythonBridge
Defined in: generated/neighbors/KNeighborsClassifier.ts:19 (opens in a new tab)
id
string
Defined in: generated/neighbors/KNeighborsClassifier.ts:16 (opens in a new tab)
opts
any
Defined in: generated/neighbors/KNeighborsClassifier.ts:17 (opens in a new tab)
Accessors
classes_
Class labels known to the classifier
Signature
classes_(): Promise<any[]>;Returns
Promise<any[]>
Defined in: generated/neighbors/KNeighborsClassifier.ts:434 (opens in a new tab)
effective_metric_
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.
Signature
effective_metric_(): Promise<string>;Returns
Promise<string>
Defined in: generated/neighbors/KNeighborsClassifier.ts:461 (opens in a new tab)
effective_metric_params_
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’.
Signature
effective_metric_params_(): Promise<any>;Returns
Promise<any>
Defined in: generated/neighbors/KNeighborsClassifier.ts:488 (opens in a new tab)
feature_names_in_
Names of features seen during fit. Defined only when X has feature names that are all strings.
Signature
feature_names_in_(): Promise<ArrayLike>;Returns
Promise<ArrayLike>
Defined in: generated/neighbors/KNeighborsClassifier.ts:542 (opens in a new tab)
n_features_in_
Number of features seen during fit.
Signature
n_features_in_(): Promise<number>;Returns
Promise<number>
Defined in: generated/neighbors/KNeighborsClassifier.ts:515 (opens in a new tab)
n_samples_fit_
Number of samples in the fitted data.
Signature
n_samples_fit_(): Promise<number>;Returns
Promise<number>
Defined in: generated/neighbors/KNeighborsClassifier.ts:569 (opens in a new tab)
outputs_2d_
False when y’s shape is (n_samples, ) or (n_samples, 1) during fit otherwise true.
Signature
outputs_2d_(): Promise<boolean>;Returns
Promise<boolean>
Defined in: generated/neighbors/KNeighborsClassifier.ts:596 (opens in a new tab)
py
Signature
py(): PythonBridge;Returns
PythonBridge
Defined in: generated/neighbors/KNeighborsClassifier.ts:84 (opens in a new tab)
Signature
py(pythonBridge: PythonBridge): void;Parameters
| Name | Type |
|---|---|
pythonBridge | PythonBridge |
Returns
void
Defined in: generated/neighbors/KNeighborsClassifier.ts:88 (opens in a new tab)
Methods
dispose()
Disposes of the underlying Python resources.
Once dispose() is called, the instance is no longer usable.
Signature
dispose(): Promise<void>;Returns
Promise<void>
Defined in: generated/neighbors/KNeighborsClassifier.ts:147 (opens in a new tab)
fit()
Fit the k-nearest neighbors classifier from the training dataset.
Signature
fit(opts: object): Promise<any>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | ArrayLike | Training data. |
opts.y? | any | Target values. |
Returns
Promise<any>
Defined in: generated/neighbors/KNeighborsClassifier.ts:164 (opens in a new tab)
init()
Initializes the underlying Python resources.
This instance is not usable until the Promise returned by init() resolves.
Signature
init(py: PythonBridge): Promise<void>;Parameters
| Name | Type |
|---|---|
py | PythonBridge |
Returns
Promise<void>
Defined in: generated/neighbors/KNeighborsClassifier.ts:97 (opens in a new tab)
kneighbors()
Find the K-neighbors of a point.
Returns indices of and distances to the neighbors of each point.
Signature
kneighbors(opts: object): Promise<ArrayLike[]>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | any | The 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. |
opts.n_neighbors? | number | Number of neighbors required for each sample. The default is the value passed to the constructor. |
opts.return_distance? | boolean | Whether or not to return the distances. Default Value true |
Returns
Promise<ArrayLike[]>
Defined in: generated/neighbors/KNeighborsClassifier.ts:208 (opens in a new tab)
kneighbors_graph()
Compute the (weighted) graph of k-Neighbors for points in X.
Signature
kneighbors_graph(opts: object): Promise<any[]>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | any | The 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). |
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. Default Value 'connectivity' |
opts.n_neighbors? | number | Number of neighbors for each sample. The default is the value passed to the constructor. |
Returns
Promise<any[]>
Defined in: generated/neighbors/KNeighborsClassifier.ts:259 (opens in a new tab)
predict()
Predict the class labels for the provided data.
Signature
predict(opts: object): Promise<ArrayLike>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | any | Test samples. |
Returns
Promise<ArrayLike>
Defined in: generated/neighbors/KNeighborsClassifier.ts:311 (opens in a new tab)
predict_proba()
Return probability estimates for the test data X.
Signature
predict_proba(opts: object): Promise<any>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | any | Test samples. |
Returns
Promise<any>
Defined in: generated/neighbors/KNeighborsClassifier.ts:346 (opens in a new tab)
score()
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.
Signature
score(opts: object): Promise<number>;Parameters
| Name | Type | Description |
|---|---|---|
opts | object | - |
opts.X? | ArrayLike[] | Test samples. |
opts.sample_weight? | ArrayLike | Sample weights. |
opts.y? | ArrayLike | True labels for X. |
Returns
Promise<number>
Defined in: generated/neighbors/KNeighborsClassifier.ts:385 (opens in a new tab)