6.5.2. scikits.learn.neighbors.NeighborsBarycenter¶
- class scikits.learn.neighbors.NeighborsBarycenter(n_neighbors=5, window_size=1)¶
Regression based on k-Nearest Neighbor Algorithm.
The target is predicted by local interpolation of the targets associated of the k-Nearest Neighbors in the training set. The interpolation weights correspond to barycenter weights.
Parameters : X : array-like, shape (n_samples, n_features)
The data points to be indexed. This array is not copied, and so modifying this data will result in bogus results.
y : array
An array representing labels for the data (only arrays of integers are supported).
n_neighbors : int
default number of neighbors.
window_size : int
Window size passed to BallTree
Notes
http://en.wikipedia.org/wiki/K-nearest_neighbor_algorithm
Examples
>>> X = [[0], [1], [2], [3]] >>> y = [0, 0, 1, 1] >>> from scikits.learn.neighbors import NeighborsBarycenter >>> neigh = NeighborsBarycenter(n_neighbors=2) >>> neigh.fit(X, y) NeighborsBarycenter(n_neighbors=2, window_size=1) >>> print neigh.predict([[1.5]]) [ 0.5]
Methods
fit(X, y[, copy]) predict(T[, n_neighbors]) Predict the target for the provided data. score(X, y) Returns the coefficient of determination of the prediction - __init__(n_neighbors=5, window_size=1)¶
Internally uses the ball tree datastructure and algorithm for fast neighbors lookups on high dimensional datasets.
- predict(T, n_neighbors=None)¶
Predict the target for the provided data.
Parameters : T : array
A 2-D array representing the test data.
n_neighbors : int
Number of neighbors to get (default is the value passed to the constructor).
Returns : y: array :
List of target values (one for each data sample).
Examples
>>> X = [[0], [1], [2]] >>> y = [0, 0, 1] >>> from scikits.learn.neighbors import NeighborsBarycenter >>> neigh = NeighborsBarycenter(n_neighbors=2) >>> neigh.fit(X, y) NeighborsBarycenter(n_neighbors=2, window_size=1) >>> print neigh.predict([[.5], [1.5]]) [ 0. 0.5]
- score(X, y)¶
Returns the coefficient of determination of the prediction
Parameters : X : array-like, shape = [n_samples, n_features]
Training set.
y : array-like, shape = [n_samples]
Returns : z : float