from sklearn.externals.six import StringIO
import pydot
from sklearn import datasets
from sklearn import tree

iris = datasets.load_iris()
clf = tree.DecisionTreeClassifier()
X = iris.data
y = iris.target

clf.fit(X, y)
dot_data = StringIO()
tree.export_graphviz(clf, out_file=dot_data,
                     feature_names=iris.feature_names,
                     class_names=iris.target_names,
                     filled=True, rounded=True,
                     special_characters=True)
graph = pydot.graph_from_dot_data(dot_data.getvalue())
graph[0].write_pdf("C:/Users/pc/Desktop/matplotlib/iris.pdf")

 

輸出如下：