objectif
Régression par plus proches voisins.
code minimal
from sklearn.neighbors import KNeighborsRegressor
from sklearn.datasets import load_boston
import numpy as np
# fallback: synthèse si dataset indisponible
try:
X, y = load_boston(return_X_y=True)
except Exception:
rng = np.random.default_rng(0); X = rng.normal(size=(100,3)); y = X[:,0]*2 + rng.normal(size=100)
knn = KNeighborsRegressor(n_neighbors=3).fit(X, y)
print(len(knn.predict(X[:2])) == 2)
utilisation
print(knn.score(X, y) <= 1.0)
variante(s) utile(s)
from sklearn.neighbors import KNeighborsRegressor
print(hasattr(KNeighborsRegressor(weights="distance"), "fit"))
notes
- Normaliser les features pour distances cohérentes.