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

I was facing the same issues, my problem got resolved using:

1. Run the command sudo port install graphviz
2. If error is coming for the port then first install port from below based on the version you are using https://guide.macports.org/chunked/installing.macports.html
3. After installation of port run command sudo port install graphviz

Restart the python kernel if you are using iPython and run again.