Vote

Implements Single Transferrable Vote, Alternative Vote, and First Past the Post

Takes a list of ballots in the form:

[
  %{"a" => 1, "b" => 2, ...},
  %{"c" => 1, "d" => 2, ...},
  ...
]

Returns a map of the results in the form:

%{
  "a" => %{exhausted: 0, round: 1, status: :elected, surplus: 20.0, votes: 40.0},
  "b" => %{exhausted: 0, round: 2, status: :excluded, votes: 8.0},
  "c" => %{exhausted: 0, round: 3, status: :elected, surplus: 0.0, votes: 20.0},
  "d" => %{votes: 17.0}
}

Installation

If available in Hex, the package can be installed by adding vote to your list of dependencies in mix.exs:

def deps do
  [
    {:vote, "~> 0.1.0"}
  ]
end

Documentation can be generated with ExDoc and published on HexDocs. Once published, the docs can be found at https://hexdocs.pm/vote.

References

• https://en.wikipedia.org/wiki/Counting_single_transferable_votes
• http://blog.opavote.com/2016/11/plain-english-explanation-of-scottish.html