## the CloneproofSSDVote classes but should not be used directly.
class CondorcetVote < ElectionVote
-
+
attr_accessor :results
def initialize(votes=nil)
def tally_vote(vote=nil)
- vote.each_with_index do |winner, index|
+ vote.each_with_index do |winners, index|
if vote.flatten.length < @candidates.length
- implied_losers = @candidates.select { |c| not vote.include?(c) }
+ implied_losers = @candidates.select { |c| not vote.flatten.include?(c) }
vote.push(implied_losers)
end
if vote.length - 1 == index
place = [place] unless place.class == Array
place.each do |loser|
+ winners = [winners] unless winners.class == Array
+ next if winners.include?(loser)
+ winners.each do |winner|
+ @votes[winner] = Hash.new unless @votes.has_key?(winner)
+ @votes[loser] = Hash.new unless @votes.has_key?(loser)
+
+ if @votes[winner].has_key?(loser)
+ @votes[winner][loser] += 1
+ else
+ @votes[winner][loser] = 1
+ end
- @votes[winner] = Hash.new unless @votes.has_key?(winner)
- @votes[loser] = Hash.new unless @votes.has_key?(loser)
-
- if @votes[winner].has_key?(loser)
- @votes[winner][loser] += 1
- else
- @votes[winner][loser] = 1
+ # make sure we have a comparable object
+ @votes[loser][winner] = 0 unless @votes[loser].has_key?( winner )
end
-
- # make sure we have a comparable object
- @votes[loser][winner] = 0 unless @votes[loser].has_key?( winner )
end
end
end
end
class PureCondorcetVote < CondorcetVote
- def result
- PureCondorcetResult.new(self)
+ def resultFactory(init)
+ PureCondorcetResult.new(init)
end
end
## directly.
class CondorcetResult < ElectionResult
+ attr_reader :matrix
+
def initialize(voteobj=nil)
unless voteobj and voteobj.kind_of?( CondorcetVote )
raise ArgumentError, "You must pass a CondorcetVote array.", caller
end
super(voteobj)
+ @matrix = voteobj.votes
end
-
+
+ def list_defeats
+ victors = Array.new
+ ties = Array.new
+ candidates = @matrix.keys.sort
+
+ candidates.each do |candidate|
+ candidates.each do |challenger|
+ next if candidate == challenger
+ diff = @matrix[candidate][challenger] - @matrix[challenger][candidate]
+ if diff > 0
+ victors << [candidate, challenger, diff]
+ elsif diff == 0 && ties.include?([challenger, candidate]) == false
+ ties << [candidate, challenger]
+ end
+ end
+ end
+
+ victories = victors.sort {|a,b| b[2] <=> a[2]}
+
+ return victories, ties
+ end
+
protected
-
def defeats(candidates=nil, votes=nil)
candidates = @election.candidates unless candidates
votes = @election.votes unless votes
end
protected
+
def condorcet
votes = @election.votes
candidates = @election.candidates
+ unless votes.length > 0 and candidates.length > 0
+ return @winners=[]
+ end
+
victors = Hash.new
candidates.each do |candidate|
victors[candidate] = Array.new
victors[winner] << loser
end
- winners = @election.candidates.find_all do |candidate|
- victors[candidate].length == @election.candidates.length - 1
+ victory_margin = 1
+ while true
+ winners = @election.candidates.find_all do |candidate|
+ victors[candidate].length == @election.candidates.length - victory_margin
+ end
+ if winners.length > 0
+ @winners = winners
+ return @winners
+ else
+ victory_margin += 1
+ end
end
-
- @winners << winners if winners.length == 1
end
end
def initialize(voteobj=nil)
super(voteobj)
@winners = self.cpssd()
+ @winners.delete nil
end
protected