Question

我正在尝试在python中构建一个决策树并将其可视化。然而，graphviz正在产生一个问题。

这是我尝试过的代码：

# -*- coding: utf-8 -*-
import pandas as pd
from pandas import Series, DataFrame
import numpy as np
import os
import matplotlib.pylab as plt
import sklearn
from sklearn.cross_validation import train_test_split
from sklearn.tree import DecisionTreeClassifier
import sklearn.metrics
from sklearn.metrics import classification_report
from sklearn import tree
from io import BytesIO as StringIO
from IPython.display import Image
import pydot
import pydotplus
import graphviz

path = "C:\\Users\\admin\\PycharmProjects\\conference\\New\\decision_tree\\"

data = pd.read_csv(path + "weights.csv")
data_clean = data.dropna()

#data_clean.dtypes()
#data_clean.describe()

predictors = data_clean[['anxiety', 'taking']]
target = data_clean['influence_score']

pred_train, pred_test, tar_train, tar_test = train_test_split(predictors,target, test_size=.2)

#pred_train.shape
#pred_test.shape
#tar_test.shape
#tar_train.shape

classifier = DecisionTreeClassifier()
classifier = classifier.fit(pred_train,tar_train)

predictons = classifier.predict(pred_test)

sklearn.metrics.confusion_matrix(tar_test,predictons)

data = StringIO()

#out_dot = path + "tree.dot"
tree.export_graphviz(classifier, out_file = data)

graph = pydotplus.graph_from_dot_data(data.getvalue())

out_tree = path + "tree_full.pdf"

graph.write_pdf(out_tree)

但是我一直收到这个错误。

  File "C:\Python27\lib\site-packages\pydotplus\graphviz.py", line 1960, in create
    'GraphViz\'s executables not found')
pydotplus.graphviz.InvocationException: GraphViz's executables not found

我已经按照安装Graphviz和pydotplus的所有步骤进行了操作，包括更改环境变量以及在python IDE中导入它们（我使用的是pycharm）。 Graphviz版本安装2.38。

我如何使这项工作。

Answer 1

我解决了。似乎我在更新环境变量时犯了一个错误。工作正常。

决策树可视化

1 个答案: