pydot.InvocationException: GraphViz's executables not found

Question

I try to run this example for decision tree learning, but get the following error message:

File \"coco.py\", line 18, in graph.write_pdf(\"iris.pdf

Answer 1

On Windows 8 this solved the same problem for me:

import os     
os.environ["PATH"] += os.pathsep + 'C:/Program Files (x86)/Graphviz2.38/bin/'