python – matplotlib：使用要素名称绘制要素重要性

import numpy as np
import matplotlib.pyplot as plt

from sklearn.datasets import make_classification
from sklearn.ensemble import ExtraTreesClassifier

# Build a classification task using 3 informative features
X,y = make_classification(n_samples=1000,n_features=10,n_informative=3,n_redundant=0,n_repeated=0,n_classes=2,random_state=0,shuffle=False)

# Build a forest and compute the feature importances
forest = ExtraTreesClassifier(n_estimators=250,random_state=0)

forest.fit(X,y)
importances = forest.feature_importances_
std = np.std([tree.feature_importances_ for tree in forest.estimators_],axis=0)
indices = np.argsort(importances)

# Plot the feature importances of the forest
plt.figure()
plt.title("Feature importances")
plt.barh(range(X.shape[1]),importances[indices],color="r",xerr=std[indices],align="center")
# If you want to define your own labels,# change indices to a list of labels on the following line.
plt.yticks(range(X.shape[1]),indices)
plt.ylim([-1,X.shape[1]])
plt.show()