Support get the data for plotting.

[MimeZoe0628]

I use SingleTreePolicyInterpreter to interpret the estimator and save as a PNG file. The image like this:

I want to display it on html by using the third-party library (e.g D3.js, Echart) in an interactive way. But I can not get the data to plot without modifing EconML source code. There is a need to get the relevant attribute to use for plotting.

[kbattocchi]

Could you expand on exactly what data you'd like us to output? In particular, how does what you want differ from what the treat method on the class provides? That method takes a set of features and returns the treatment suggested by the tree for each row.