Chamberlain-Courant, Approval, Range Types

[andrewmhong]

Added Chamberlain-Courant, Approval, Range election type classes; updated PreferenceProfile class (in profile.py) with new RangeBallot class (in ballot.py)

[realdavemccune]

I was looking at the Cham Cour code, and sorry if I missed it but how are partial ballots being processed? Or does this function assume complete ballots? Also, does the function handle ties? Ties are obnoxious so I would deal with them in the easiest possible way and just document the choice.

[andrewmhong]

1. Partial ballots: The code runs with partial ballots, but am now realizing it does not handle them correctly. It stops adding Borda weights when the ballot runs out (all ranks read), and does not distribute remaining unranked Borda weights correctly. I'll work on this. How would you like to handle those partial ballots/remaining Borda weights?
2. Ties: The code submitted kind of handles ties. It simply chooses the first indexed committee when sorting committee total Borda scores—so pseudo-randomly.