K-Nearest Neighbors

Problem

Predict the class label of x_test by majority vote among its k nearest neighbors in X_train.

Distance is Euclidean. Ties in the vote are broken by choosing the smallest label.

Hint

Sort by distance, take top k, count labels, break ties by smallest label.

case 1

in: [[[0,0],[0,1],[10,10],[10,11]],["a","a","b","b"],[1,0],2]

expected: "a"

case 2

in: [[[0,0],[0,1],[10,10],[10,11]],["a","a","b","b"],[9,10],2]

expected: "b"

case 3

in: [[[1],[2],[3],[10]],[0,0,0,1],[4],3]

expected: 0

Starter codePython

def knn_predict(X_train, y_train, x_test, k):
    # Your code here
    pass

3 test cases · run your code against them in the editor