用sklearn KNN显示最近的邻居

Question

我知道在用sklearn拟合KNN模型后，我可以预测这样的标签：

from sklearn.neighbors import KNeighborsClassifier
knn = KNeighborsClassifier(n_neighbors=3)
knn.fit([3,1,4,3], [1,0,1,1)]
In: knn.predict([3])
Out: array([0])

但是有可能让KNN显示最近的邻居是什么吗？在伪代码中，这看起来像：

In: knn.show_nearest_neighbors([3], n_neighbors = 3)
Out: array([3,3,4])

Answer 1

您可以使用knn.kneighbors([[3]], n_neighbors=3, return_distance=False)来获取邻居的索引：

import numpy as np
from sklearn.neighbors import KNeighborsClassifier
knn = KNeighborsClassifier(n_neighbors=3)
X = np.array([[3],[1],[4],[3]])
knn.fit(X, [1,0,1,1])
l = knn.kneighbors([[3]], n_neighbors=3, return_distance=False)
X[l].ravel()

输出：array([3, 3, 4])。