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:
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
## 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
+# 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
+
def initialize(votes=nil)
@candidates = Array.new
votes.each do |vote|
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
- def verify_vote(vote=nil)
- vote.instance_of?( Array ) and
- vote == vote.uniq
- end
end
class InstantRunoffLogicVote < InstantRunoffVote
## 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)
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
class RangeResult < PluralityResult
-#!/usr/bin/ruby -Ilib
-
require 'test/unit'
require 'rubyvote/election'
require 'rubyvote/condorcet'
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
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
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
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
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
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
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_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
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
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
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']
- 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
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]
projects / rubyvote / commitdiff