决策树可视化

方式一：输出形成dot文件，然后使用graphviz的dot命令将dot文件转换为pdf
from sklearn import tree
with open(‘决策树.dot’, ‘w’) as f:
# 将模型model输出到给定的文件中
f = tree.export_graphviz(model, out_file=f)
# 命令行执行dot命令： dot -Tpdf iris.dot -o iris.pdf
# 方式二：直接使用pydotplus插件生成pdf文件
from sklearn import tree
import pydotplus
dot_data = tree.export_graphviz(model, out_file=None)
graph = pydotplus.graph_from_dot_data(dot_data)
#graph.write_pdf(“决策树.pdf”)
graph.write_png(“决策树.png”)
#方式三：直接生成图片
from sklearn import tree
from IPython.display import Image
import pydotplus
dot_data = tree.export_graphviz(model, out_file=None,
feature_names=[‘sepal length’, ‘sepal width’, ‘petal length’, ‘petal width’],
class_names=[‘Iris-setosa’, ‘Iris-versicolor’, ‘Iris-virginica’],
filled=True, rounded=True,
special_characters=True)
graph = pydotplus.graph_from_dot_data(dot_data)
Image(graph.create_png())