Example to run KNN algorithm using python

Question

Can you give an example of using the KNN algorithm using pyhton? Thanks

Answer 1

Have a look at this one:

from sklearn.datasets import load_iris
from sklearn.neighbors import KNeighborsClassifier
import numpy as np
from sklearn.model_selection import train_test_split 
iris_dataset=load_iris()
X_train, X_test, y_train, y_test = train_test_split(iris_dataset["data"], iris_dataset["target"], random_state=0)
kn = KNeighborsClassifier(n_neighbors=1)
kn.fit(X_train, y_train)   
x_new = np.array([[5, 2.9, 1, 0.2]])
prediction = kn.predict(x_new)
print("Predicted target value: {}\n".format(prediction))
print("Predicted feature name: {}\n".format
    (iris_dataset["target_names"][prediction]))
print("Test score: {:.2f}".format(kn.score(X_test, y_test)))