a number of improvements

- switched IRV's add_vote to tally_vote to make it consistent
- added description and documentation to each method/time
- fixed typo in README
- added a new IRV test (which i'm not sure is wrong) but which was
  causing big problems on selectricity

git-svn-id: svn://rubyforge.org/var/svn/rubyvote/trunk@49 1440c7f4-e209-0410-9a04-881b5eb134a8

diff --git a/README b/README
index efd0ddfff5d9f6098fea1f858ab5e56883ffb27f..a603a0462cae565f1a3beb90ea72fe0c88ddc436 100644 (file)
--- a/README
+++ b/README
@@ -51,7 +51,7 @@ simply takes the raw "tallies" of votes and computes the results.
 Currently, it does not include any sample interfaces (although if
 contributed, these may be included).
 
 Currently, it does not include any sample interfaces (although if
 contributed, these may be included).
 

-`RubyVote` current includes a set of classes to tally votes and compute
+`RubyVote` currently includes a set of classes to tally votes and compute

 winners in elections or votes using a series of different methods.
 Currently these include:
 
 winners in elections or votes using a series of different methods.
 Currently these include:
 

diff --git a/lib/rubyvote/election.rb b/lib/rubyvote/election.rb
index 3655a034e7575d7be3541ab49e1be12a80fb0c17..1d98d91848611d9b5a3fa5dd2bb2d4bc95de8404 100644 (file)
--- a/lib/rubyvote/election.rb
+++ b/lib/rubyvote/election.rb
@@ -62,7 +62,7 @@ class ElectionVote
   end
 
   # by default, this does nothing. it must be redefined in any subclass
   end
 
   # by default, this does nothing. it must be redefined in any subclass

-  def tally_vote
+  def tally_vote(vote)

     self.verify_vote(vote)
   end
 
     self.verify_vote(vote)
   end
 


@@ -108,10 +108,15 @@ end
 ## Election Result Classes
 ##
 
 ## 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.
-
+# ElectionResult and its subclasses are used to identify and report the results
+# of an election. In almost all cases, these will be returned by the #results
+# method of a corresponding ElectionVote subclass.
+#
+# Each ElectionResult object has the following methods:
+#
+#  * #winner? -- return Boolean as to the winner or winners of an election
+#  * #winners -- an array of winners of the election
+#  * #ranked_candidates -- (where available) a list of ranked candidates

 class ElectionResult
   attr_reader :winners
   attr_reader :election
 class ElectionResult
   attr_reader :winners
   attr_reader :election

diff --git a/lib/rubyvote/irv.rb b/lib/rubyvote/irv.rb
index c3fabe6e488de75352c1ae53305e0a1b0785022c..aa941158a880a5ee548a6ae8579fbc7433dae196 100644 (file)
--- a/lib/rubyvote/irv.rb
+++ b/lib/rubyvote/irv.rb
@@ -1,4 +1,18 @@
+# IRV is a preferential voting system used widely for government elections
+# in Australia and New Zealand and elsewhere. IRV asks voters to rank
+# candidates in preference and then holds a series of "runoff" elections
+# by eliminating the weakest candidate and recomputing the election
+# results until there exists a candidate who has a majority of the
+# remaining votes.
+
+# Example::
+
+#   require 'irv'
+#   vote_array = [ ["A", "B"],  ["B", "A"], ["B", "A"] ]
+#   resultobject = InstantRunoffVote.new(vote_array).result
+#

 class InstantRunoffVote < ElectionVote
 class InstantRunoffVote < ElectionVote

+

   def initialize(votes=nil)
     @candidates = Array.new
     votes.each do |vote|
   def initialize(votes=nil)
     @candidates = Array.new
     votes.each do |vote|


@@ -15,22 +29,22 @@ class InstantRunoffVote < ElectionVote
   end
   
   protected
   end
   
   protected

-  def tally_vote(vote)
-    votecopy = vote.dup
-    candidate = votecopy.shift
-    votes[candidate] = [0, Hash.new] unless votes.has_key?(candidate)
-    votes[candidate][0] += 1
-    if votes[candidate][1].has_key?(votecopy)
-      votes[candidate][1][votecopy] += 1
-    else
-      votes[candidate][1][votecopy] = 1
+    def vote_valid?(vote = nil)
+      super && vote.is_a?(Array) && vote == vote.uniq
+    end
+
+    def tally_vote(vote)
+      votecopy = vote.dup
+      candidate = votecopy.shift
+      votes[candidate] = [0, Hash.new] unless votes.has_key?(candidate)
+      votes[candidate][0] += 1
+      if votes[candidate][1].has_key?(votecopy)
+        votes[candidate][1][votecopy] += 1
+      else
+        votes[candidate][1][votecopy] = 1
+      end

     end
     end

-  end

 
 

-  def verify_vote(vote=nil)
-    vote.instance_of?( Array ) and
-      vote == vote.uniq
-  end

 end
 
 class InstantRunoffLogicVote < InstantRunoffVote
 end
 
 class InstantRunoffLogicVote < InstantRunoffVote

diff --git a/lib/rubyvote/positional.rb b/lib/rubyvote/positional.rb
index 056194b519dc88f2a79adc3617bf95f250fa3310..d72f8a780b0004829400fef56cfafadf9615c745 100644 (file)
--- a/lib/rubyvote/positional.rb
+++ b/lib/rubyvote/positional.rb
@@ -29,6 +29,19 @@
 ## These classes inherit from and/or are modeled after the classes in
 ## election.rb and condorcet.rb
 
 ## These classes inherit from and/or are modeled after the classes in
 ## election.rb and condorcet.rb
 

+# Borda is a positional voting system and, as a result, takes a list of
+# ranked candidates and assigns points to each candidates based on their
+# order. In Borda, there are *n* candidate and the first candidates is
+# assigned *n* - 1 points and each subsequent candidate is assigned one
+# less point. The candidate is assigned no points.
+#
+# Currently, all candidates should be ranked in each ballot.
+#
+# Example::
+#
+#   require 'positional'
+#   vote_array = [ ["A", "B"],  ["B", "A"], ["B", "A"] ]
+#   resultobject = BordaVote.new(vote_array).result

 class BordaVote < ElectionVote
 
   def initialize(votes=nil)
 class BordaVote < ElectionVote
 
   def initialize(votes=nil)

diff --git a/lib/rubyvote/range.rb b/lib/rubyvote/range.rb
index 5c01f6815899711e9170b6851a53c23fece5e2fa..cd4df87e3db29297901ba63bb38e056487ca9bd1 100644 (file)
--- a/lib/rubyvote/range.rb
+++ b/lib/rubyvote/range.rb
@@ -12,20 +12,20 @@ class RangeVote < ElectionVote
   end
 
   protected
   end
 
   protected

-  def verify_vote(vote=nil)
-    vote.instance_of?(Hash) && vote.all?{|c,score| @valid_range.include?(score)}
-  end
+    def vote_valid?(vote=nil)
+      super && vote.is_a?(Hash) && vote.all?{|c,score| @valid_range.include?(score)}
+    end

 
 

-  def tally_vote(vote)
-    vote.each do |candidate, score|
-      if @votes.has_key?(candidate)
-        @votes[candidate] += score
-      else
-        @votes[candidate] = score
-        @candidates << candidate
+    def tally_vote(vote)
+      vote.each do |candidate, score|
+        if @votes.has_key?(candidate)
+          @votes[candidate] += score
+        else
+          @votes[candidate] = score
+          @candidates << candidate
+        end

       end
     end
       end
     end

-  end

 end
 
 class RangeResult < PluralityResult
 end
 
 class RangeResult < PluralityResult

diff --git a/test/condorcet_test.rb b/test/condorcet_test.rb
index b2d5dc46ad9864d4787c78596551aae1cfac2ab9..0e45d4a7d0b61197a8b382571f5609cc3320926c 100644 (file)
--- a/test/condorcet_test.rb
+++ b/test/condorcet_test.rb
@@ -1,5 +1,3 @@
-#!/usr/bin/ruby -Ilib
-

 require 'test/unit'
 require 'rubyvote/election'
 require 'rubyvote/condorcet'
 require 'test/unit'
 require 'rubyvote/election'
 require 'rubyvote/condorcet'


@@ -18,7 +16,7 @@ class TestCondorcetVote < Test::Unit::TestCase
     2.times {vote_array << "BAC".split("")}
 
     assert_equal "B", PureCondorcetVote.new(vote_array).result.winners[0]
     2.times {vote_array << "BAC".split("")}
 
     assert_equal "B", PureCondorcetVote.new(vote_array).result.winners[0]

-    assert_equal [['B'], ['A'], ['C']], PureCondorcetVote.new(vote_array).results
+    assert_equal [['B'], ['A'], ['C']], PureCondorcetVote.new(vote_array).result.ranked_candidates

   end
 
   def test_condorcet_2
   end
 
   def test_condorcet_2


@@ -29,7 +27,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     v = PureCondorcetVote.new(vote_array)
     assert_equal ["6", "7"], v.result.winners
 
     v = PureCondorcetVote.new(vote_array)
     assert_equal ["6", "7"], v.result.winners

-    assert_equal [['6', '7'], ['8']], v.results
+    assert_equal [['6', '7'], ['8']], v.result.ranked_candidates

   end
 
   def test_ssd_empty
   end
 
   def test_ssd_empty


@@ -51,7 +49,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     assert_equal "E", CloneproofSSDVote.new(vote_array).result.winners[0]
     assert_equal [['E'], ['A'], ['C'], ['B'], ['D']], 
 
     assert_equal "E", CloneproofSSDVote.new(vote_array).result.winners[0]
     assert_equal [['E'], ['A'], ['C'], ['B'], ['D']], 

-                 CloneproofSSDVote.new(vote_array).results
+                 CloneproofSSDVote.new(vote_array).result.ranked_candidates

   end
 
   def test_ssd2
   end
 
   def test_ssd2


@@ -68,7 +66,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     assert_equal "D", CloneproofSSDVote.new(vote_array).result.winners[0] 
     assert_equal [['D'], ['A'], ['C'], ['B']], 
 
     assert_equal "D", CloneproofSSDVote.new(vote_array).result.winners[0] 
     assert_equal [['D'], ['A'], ['C'], ['B']], 

-                 CloneproofSSDVote.new(vote_array).results
+                 CloneproofSSDVote.new(vote_array).result.ranked_candidates

   end
 
   def test_ssd3
   end
 
   def test_ssd3


@@ -80,7 +78,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     assert_equal "B", CloneproofSSDVote.new(vote_array).result.winners[0]
     assert_equal [['B'], ['C'], ['D'], ['A']], 
 
     assert_equal "B", CloneproofSSDVote.new(vote_array).result.winners[0]
     assert_equal [['B'], ['C'], ['D'], ['A']], 

-                 CloneproofSSDVote.new(vote_array).results
+                 CloneproofSSDVote.new(vote_array).result.ranked_candidates

   end
 
   def test_ssd_incomplete_votes
   end
 
   def test_ssd_incomplete_votes


@@ -93,7 +91,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal "B", vote.result.winners[0]
 
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal "B", vote.result.winners[0]

-    assert_equal [['B'], ['C'], ['D'], ['A']], vote.results
+    assert_equal [['B'], ['C'], ['D'], ['A']], vote.result.ranked_candidates

   end
 
   def test_ssd_incomplete_votes_2
   end
 
   def test_ssd_incomplete_votes_2


@@ -106,7 +104,7 @@ class TestCondorcetVote < Test::Unit::TestCase
 
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal "B", vote.result.winners[0]
 
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal "B", vote.result.winners[0]

-    assert_equal [['B'], ['C'], ['D'], ['A']], vote.results
+    assert_equal [['B'], ['C'], ['D'], ['A']], vote.result.ranked_candidates

   end
 
   # 
   end
 
   # 


@@ -118,7 +116,7 @@ class TestCondorcetVote < Test::Unit::TestCase
   def test_ssd_single_vote
     vote = CloneproofSSDVote.new([[78]])
     assert_equal 78, vote.result.winners[0]
   def test_ssd_single_vote
     vote = CloneproofSSDVote.new([[78]])
     assert_equal 78, vote.result.winners[0]

-    assert_equal [[78]], vote.results
+    assert_equal [[78]], vote.result.ranked_candidates

   end
 
   def test_ssd_sparse
   end
 
   def test_ssd_sparse


@@ -126,8 +124,8 @@ class TestCondorcetVote < Test::Unit::TestCase
     vote_array << ['B', 'D']
     vote_array << ['A', 'C']
     vote_array << ['E', 'C']
     vote_array << ['B', 'D']
     vote_array << ['A', 'C']
     vote_array << ['E', 'C']

-    results = CloneproofSSDVote.new(vote_array).results
-    assert_equal 5, results.flatten.size
+    ranked_candidates = CloneproofSSDVote.new(vote_array).result.ranked_candidates
+    assert_equal 5, ranked_candidates.flatten.size

   end
 
   def test_ssd_sparse_2
   end
 
   def test_ssd_sparse_2


@@ -136,7 +134,7 @@ class TestCondorcetVote < Test::Unit::TestCase
     vote_array << [64, 65, 66, 63]
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal 65, vote.result.winners[0]
     vote_array << [64, 65, 66, 63]
     vote = CloneproofSSDVote.new(vote_array)
     assert_equal 65, vote.result.winners[0]

-    assert_equal [[65, 64], [63, 66]], vote.results
+    assert_equal [[65, 64], [63, 66]], vote.result.ranked_candidates

   end
 
   def test_ssd_multiple_equivalent
   end
 
   def test_ssd_multiple_equivalent


@@ -144,19 +142,17 @@ class TestCondorcetVote < Test::Unit::TestCase
     vote_array << ['B', ['A', 'C'], 'D']
     vote_array << ['A', 'C']
     vote_array << [['E', 'D'], 'C']
     vote_array << ['B', ['A', 'C'], 'D']
     vote_array << ['A', 'C']
     vote_array << [['E', 'D'], 'C']

-    results = CloneproofSSDVote.new(vote_array).results
-    assert_equal 5, results.flatten.size
-    assert_equal [['A', 'C'], ['B', 'D'], ['E']], results
+    ranked_candidates = CloneproofSSDVote.new(vote_array).result.ranked_candidates
+    assert_equal 5, ranked_candidates.flatten.size
+    assert_equal [['A', 'C'], ['B', 'D'], ['E']], ranked_candidates

   end
 
   def test_ssd_multiple_equivalent_2
     vote_array = Array.new
     vote_array << ['B', ['A'], 'C']
     vote_array << ['B', ['C'], 'A']
   end
 
   def test_ssd_multiple_equivalent_2
     vote_array = Array.new
     vote_array << ['B', ['A'], 'C']
     vote_array << ['B', ['C'], 'A']

-    results = CloneproofSSDVote.new(vote_array).results
-    assert_equal 3, results.flatten.size
-    assert_equal [['B'], ['A', 'C']], results
+    ranked_candidates = CloneproofSSDVote.new(vote_array).result.ranked_candidates
+    assert_equal 3, ranked_candidates.flatten.size
+    assert_equal [['B'], ['A', 'C']], ranked_candidates

   end
   end

-
-

 end
 end

diff --git a/test/irv_test.rb b/test/irv_test.rb
index d3a57a7c7d8cec68e31a4c85cf0ba89c675cea2b..2974296c2cdfa3e72e535af36372ace60d8a0bd0 100644 (file)
--- a/test/irv_test.rb
+++ b/test/irv_test.rb
@@ -56,7 +56,68 @@ class TestRunoffVote < Test::Unit::TestCase
 
     assert_equal( "C", InstantRunoffVote.new(vote_array).result.winners[0] )
   end
 
     assert_equal( "C", InstantRunoffVote.new(vote_array).result.winners[0] )
   end

-  
+ 
+  def test_irv4
+    # this was causing selectricity to crash
+
+    raw_vote_array = ["GFECADBIH", "ABCDEFGHI", "IGHBADFCE",
+                      "FABCDEGHI", "ABCDEFGHI", "ABCDEFGHI",
+                      "ABCDEFGHI", "ABCDEFGHI", "ABCDEFGHI",
+                      "EHBICDAGF", "ECGDFBIAH", "BDHIGFECA",
+                      "ECDBFIHAG", "FEDBCAHIG", "CDABHIEFG",
+                      "FCBDIHAEG", "AIHFBECGD", "BACHDEFIG",
+                      "CDEFIBHAG", "BDICAFEGH", "ABCDEFGHI",
+                      "CBIHDFAEG", "ABCDEFGHI", "CDFIBAGEH",
+                      "ECDBIFHGA", "BDACEHFIG", "CFDIHABEG",
+                      "ADCFGBIHE", "CDHIBEAGF", "ABCFDHIEG",
+                      "ABCDEFGHI", "DCFHIBAGE", "CDFEABHIG",
+                      "DFHIBEAGC", "EDCBFIGAH", "BAECDFHGI",
+                      "BAHCEDFGI", "HBCDIAFEG", "ABCDEFGHI",
+                      "ABCDEFGHI", "EDCBIGAHF", "EIBDCGAFH",
+                      "HIACGDFBE", "DEACBIFGH", "CIDEFABGH",
+                      "ABHDIECGF", "ECIDBFGHA", "CEDFBHIGA",
+                      "ABHCEIDFG", "CFDBEIHGA", "ICEDBGFAH",
+                      "EDCIFBAGH", "ECFDBAHGI", "EBCADFIGH",
+                      "EFBHAGICD", "CDBIEFAHG", "ABCDEFGHI",
+                      "FCDBEIHGA", "AIEBDCFHG", "CDFEBIGAH",
+                      "CABDEFGHI", "DCEIBFGHA", "EADCIBHFG",
+                      "DBCAHIGEF", "EDFBCIAHG", "EDCBIHAGF",
+                      "CFIAEDGHB", "CDEIHABGF", "CEBHIDAFG",
+                      "BCFEDIHAG", "CDIHBFGEA", "CFEDIGBAH",
+                      "IHFEADCBG", "EBDCIGAHF", "BCEDFIAGH",
+                      "ABHEGICDF", "CABFHDIEG", "HEABDCFGI",
+                      "CDEBFAIHG", "CDBFIHAGE", "ABGFEDHCI",
+                      "IBHDCAEFG", "EBDICHAFG", "ABCDEFGHI",
+                      "EFBHAICGD", "CBDFHAIEG", "CDBAEIHGF",
+                      "ABCDEFGHI", "BECDHIFGA", "DAGCIHFBE",
+                      "BIECDGAHF", "ABCDEFGHI", "ACDEBHIFG",
+                      "AEBCIDHFG", "ABCDEFGHI", "ABCDEFGHI",
+                      "ABCDEFGHI", "ABCDEFGHI", "ABCDEFGHI",
+                      "ABCDEFGHI", "ECFDIHBAG", "BIDCHEAGF",
+                      "BCEDFIGHA", "CBDAFEGHI", "ABCDEFGHI",
+                      "FACEGDHBI", "ABCDEFGHI", "FDIBCGHAE",
+                      "EBIHADCFG", "EDBIHAGCF", "AHDICBFEG",
+                      "DCBIHAGFE", "CABFIDEHG", "IFCBHADEG",
+                      "EDCFHIBAG", "DCABEFGHI", "FCBDIGHEA",
+                      "ABCDEFGHI", "HBACIDEFG", "ABCDEFGHI",
+                      "ABCDEFGHI", "EADCBIHGF", "BDCIHAGFE",
+                      "ABCDEFGHI", "ABCDEFGHI", "ABCDEFGHI",
+                      "ABCDEFGHI", "ABCDEFGHI", "ICDGAHBEF",
+                      "EGBCFIHDA", "DFGACHIEB", "BCAGDFHIE",
+                      "DBGHCEAFI", "IGHEBCADF", "FEDIHBCAG",
+                      "HAICBGEFD", "EBFDAICGH", "ECGAHFIBD",
+                      "GEFICAHDB", "ACEHGIBDF", "EGIFBHCAD",
+                      "GHFEDCIBA", "DGAEHFICB", "HGDICBAFE",
+                      "HEACGDBFI", "IAGDFHCEB", "EGIACHBDF",
+                      "CBFGDIEAH", "CGAIBDEFH", "AHEDIGCBF",
+                      "BAEFHIDCG", "BIDGAFCHE", "CHBAEDFIG",
+                      "IBGCFADEH", "GHACDEFIB", "CFDBEAHIG",
+                      "GDEFAICHB"]
+    vote_array = raw_vote_array.collect {|v| v.split("")}
+    print InstantRunoffVote.new(vote_array).result.winners, "\n"
+    assert_equal(true, InstantRunoffVote.new(vote_array).result.winner?)
+  end
+

   def test_irv_logic_empty
     vote_array = Array.new
     assert_nil InstantRunoffLogicVote.new(vote_array).result.winners[0]
   def test_irv_logic_empty
     vote_array = Array.new
     assert_nil InstantRunoffLogicVote.new(vote_array).result.winners[0]