更新、更全的《機器學習》的更新網站,更有python、go、數據結構與算法、爬蟲、人工智能教學等着你:http://www.javashuo.com/article/p-vozphyqp-cm.htmlpython
import pandas as pd from sklearn import datasets from sklearn.preprocessing import LabelEncoder from sklearn.ensemble import RandomForestClassifier from sklearn.model_selection import train_test_split from sklearn.metrics import accuracy_score
X, y = datasets.load_wine(return_X_y=True)
le = LabelEncoder() # 把label轉換爲0和1 y = le.fit_transform(y) # 訓練集和測試集比例爲7:3 X_train, X_test, y_train, y_test = train_test_split( X, y, test_size=0.30, random_state=1)
rf = RandomForestClassifier(n_estimators=1000, criterion='gini', max_features='sqrt', min_samples_split=2, bootstrap=True) rf = rf.fit(X_train, y_train)
y_train_pred = rf.predict(X_train) y_test_pred = rf.predict(X_test) # 度量隨機森林的準確性 tree_train = accuracy_score(y_train, y_train_pred) tree_test = accuracy_score(y_test, y_test_pred) print('隨機森林訓練集和測試集準確度分別爲:{:.2f}/{:.2f}'.format(tree_train, tree_test))
隨機森林訓練集和測試集準確度分別爲:1.00/0.98