Added list of changes submitted by Jeff Rose <jeff@rosejn.net>.

[rubyvote] / lib / election.rb

diff --git a/lib/election.rb b/lib/election.rb
deleted file mode 100644 (file)
index 7fd8396..0000000
--- a/lib/election.rb
+++ /dev/null
@@ -1,160 +0,0 @@
-# election library -- a ruby library for elections
-# copyright © 2005 MIT Media Lab and Benjamin Mako Hill
-
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 2 of the License, or
-# (at your option) any later version.
-
-# This program is distributed in the hope that it will be useful, but
-# WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-# General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, write to the Free Software
-# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 02110-1301, USA.
-
-#################################################################
-## ==== election.rb ====
-##
-## This file contains the core ElectionVote and ElectionResults
-## classes and the most common and simple election methods including
-## plurality and approval voting.
-#################################################################
-
-##################################################################
-## ElectionVote Classes and SubClasses
-##
-## There classes are used to store, verify, and "tally" (i.e. count
-## votes for the standard Election superclass and for the most common
-## types of elections.
-
-class ElectionVote
-  attr_reader :votes
-  attr_reader :candidates
-
-  def initialize(votes=nil)
-    @votes = Hash.new unless defined?(@votes)
-    @candidates = Array.new unless defined?(@candidates)
-
-    if votes
-      if votes.instance_of?( Array )
-        votes.each do |vote|
-          self.tally_vote(vote) if self.verify_vote(vote)
-        end
-      else
-        raise ElectionError, "Votes must be in the form of an array.", caller
-      end
-    end
-  end
-
-  protected
-  # by default, this is set to look if the vote is defined. it should
-  # be overridden in each class
-  def verify_vote(vote=nil)
-    vote ? true : false
-  end
-
-  # by default, this does nothing. it must be redefined in any subclass
-  def tally_vote
-    self.verify_vote(vote)
-  end
-end
-
-class PluralityVote < ElectionVote
-  def result
-    PluralityResult.new(self)
-  end
-  
-  protected
-  def verify_vote(vote=nil)
-    vote.instance_of?( String )
-  end
-
-  def tally_vote(candidate)
-    if @votes.has_key?(candidate)
-      @votes[candidate] += 1
-    else
-      @votes[candidate] = 1
-      @candidates << candidate
-    end
-  end
-end
-
-class ApprovalVote < PluralityVote
-  def result
-    ApprovalResult.new(self)
-  end
-
-  protected
-  def verify_vote(vote=nil)
-    vote.instance_of?( Array ) and vote.length >= 1
-  end
-
-  def tally_vote(approvals)
-    approvals.each {|candidate| super(candidate)}
-  end
-end
-
-
-##################################################################
-## Election Result Classes
-##
-
-## There classes are used to compute and report the results of an
-## election. In almost all cases, these will be returned by the
-## #results method of a corresponding ElectionVote subclass.
-
-class ElectionResult
-  attr_reader :winners
-
-  def initialize(voteobj=nil)
-    unless voteobj and voteobj.kind_of?( ElectionVote )
-      raise ArgumentError, "You must pass a ElectionVote array.", caller
-    end
-
-    @election = voteobj
-    @winners = Array.new
-  end
-
-  def winner
-    @winners[0] if @winners.length > 0
-  end
-
-  def winner?
-    @winners.length > 0
-  end
-
-end
-
-class PluralityResult < ElectionResult
-  attr_reader :ranked_candidates
-
-  def initialize(voteobj=nil)
-    super(voteobj)
-
-    votes = @election.votes
-    candidates = @election.candidates
-    
-    @ranked_candidates = votes.sort do |a, b|
-      b[1] <=> a[1]
-    end.collect {|a| a[0]}
-    
-    # winners are anyone who has the same number of votes as the
-    # first person
-    @winners = @ranked_candidates.find_all do |i|
-      votes[i] == votes[@ranked_candidates[0]]
-    end
-  end
-end
-
-# this class is complete because results for approval are computed
-# identically to results from plurality
-class ApprovalResult < PluralityResult
-end
-  
-class ElectionError < ArgumentError
-end
-