与sklearn决策树图的Pydot错误

时间:2015-02-07 20:43:27

标签: python scikit-learn pydot

我正在尝试使用以下来自sklearn(http://scikit-learn.org/stable/modules/tree.html)的代码:

from sklearn.externals.six import StringIO
import pydot 
dot_data = StringIO()
tree.export_graphviz(clf, out_file=dot_data)
graph = pydot.graph_from_dot_data(dot_data.getvalue())
graph.write_pdf("iris.pdf")

我已安装pydot==1.0.2,当我使用Ipython notebook运行此代码时,会出现以下错误。

InvocationException                       Traceback (most recent call last)
<ipython-input-22-18c25f6a061c> in <module>()
  4 tree.export_graphviz(clf, out_file=dot_data)
  5 graph = pydot.graph_from_dot_data(dot_data.getvalue())
----> 6 graph.write_pdf("iris.pdf")

 /Users/aj/anaconda/lib/python2.7/site-packages/pydot.pyc in <lambda>(path, f,     prog)
 1600             self.__setattr__(
 1601                 'write_'+frmt,
-> 1602                 lambda path, f=frmt, prog=self.prog : self.write(path,         format=f, prog=prog))
1603 
1604             f = self.__dict__['write_'+frmt]

/Users/aj/anaconda/lib/python2.7/site-packages/pydot.pyc in write(self, path, prog, format)
1694             dot_fd.write(self.to_string())
1695         else:
-> 1696             dot_fd.write(self.create(prog, format))
 1697         dot_fd.close()
 1698 

 /Users/aj/anaconda/lib/python2.7/site-packages/pydot.pyc in create(self, prog,  format)
 1794             raise InvocationException(
 1795                 'Program terminated with status: %d. stderr follows: %s'  % (
 -> 1796                     status, stderr_output) )
  1797         elif stderr_output:
  1798             print stderr_output

InvocationException: Program terminated with status: 1. stderr follows: Format: "pdf" not recognized. Use one of

无论我将其更改为何种格式,都会出现同样的错误。我在Mac OS X Yosemite上运行它。

任何建议都会非常感激。

1 个答案:

答案 0 :(得分:0)

事实上,这是graphviz的问题。显然,它需要XQuartz包(http://xquartz.macosforge.org/landing/),安装后,一切正常。