Implement exclusion of parcels by value + Senate STV

html/index.html

@@ -40,7 +40,7 @@
 				<select id="selPreset" onchange="changePreset()">
 					<option value="scottish" selected>Scottish STV</option>
 					<option value="stvc">pyRCV STV-C</option>
-					<!--<option value="senate">Australian Senate STV</option>-->
+					<option value="senate">Australian Senate STV</option>
 					<option value="wright">Wright STV</option>
 					<option value="prsa77">PRSA 1977</option>
 				</select>
@@ -119,7 +119,7 @@
 				<select id="selExclusion">
 					<option value="one_round" selected>Exclude in one round</option>
 					<option value="parcels_by_order">Exclude by parcel (by order)</option>
-					<!--<option value="parcels_by_value">Exclude by parcel (by value)</option>-->
+					<option value="parcels_by_value">Exclude by parcel (by value)</option>
 				</select>
 			</label>
 			<br>

pyRCV2/method/base_stv.py

@@ -20,6 +20,8 @@ from pyRCV2.model import CandidateState, CountCard, CountCompleted, CountStepRes
 from pyRCV2.numbers import Num, Rational
 from pyRCV2.safedict import SafeDict
 
+import itertools
+
 class STVException(Exception):
 	pass
 
@@ -535,11 +537,28 @@ class WIGSTVCounter(BaseSTVCounter):
 	
 	def do_exclusion(self, candidate_excluded, count_card):
 		if self.options['exclusion'] == 'parcels_by_order':
+			if len(count_card.parcels) > 0:
 				parcel = count_card.parcels[0]
 				next_preferences, total_ballots, total_votes, next_exhausted, exhausted_ballots, exhausted_votes = self.next_preferences([parcel])
+			else:
+				# TODO: Skip this entirely if this is the case
+				parcel = []
 			count_card.parcels.remove(parcel)
 		elif self.options['exclusion'] == 'parcels_by_value':
-			raise Exception('Not implemented')
+			# Sort the parcels by value
+			ballots = [(b, bv) for p in count_card.parcels for b, bv in p]
+			__pragma__('opov')
+			ballots.sort(key=lambda x: x[1] / x[0].value.to_rational(), reverse=True)
+			count_card.parcels = [list(g) for k, g in itertools.groupby(ballots, lambda x: x[1] / x[0].value.to_rational())]
+			__pragma__('noopov')
+			
+			if len(count_card.parcels) > 0:
+				parcel = count_card.parcels[0]
+				count_card.parcels.remove(parcel)
+			else:
+				parcel = []
+			
+			next_preferences, total_ballots, total_votes, next_exhausted, exhausted_ballots, exhausted_votes = self.next_preferences([parcel])
 		else: # one_round
 			next_preferences, total_ballots, total_votes, next_exhausted, exhausted_ballots, exhausted_votes = self.next_preferences(count_card.parcels)
 			count_card.parcels = []
@@ -573,6 +592,9 @@ class WIGSTVCounter(BaseSTVCounter):
 		__pragma__('noopov')
 		
 		if len(count_card.parcels) == 0:
+			__pragma__('opov')
+			count_card.transfers -= count_card.votes
+			__pragma__('noopov')
 			count_card.state = CandidateState.EXCLUDED
 
 class UIGSTVCounter(WIGSTVCounter):
@@ -590,14 +612,14 @@ class UIGSTVCounter(WIGSTVCounter):
 		
 		if self.options['papers'] == 'transferable':
 			__pragma__('opov')
-			transferable_ballots = total_ballots - exhausted_ballots
+			transferable_ballots = total_ballots - exhausted_ballots # Num
-			transferable_votes = total_votes.to_num() - exhausted_votes.to_num()
+			transferable_votes = total_votes - exhausted_votes # Rational
 			__pragma__('noopov')
 		
 		for candidate, x in next_preferences.items():
 			cand_ballots = x[0]
-			num_ballots = x[1]
+			num_ballots = x[1] # Num
-			num_votes = x[2]
+			num_votes = x[2] # Rational
 			
 			new_parcel = []
 			if len(cand_ballots) > 0:
@@ -619,11 +641,11 @@ class UIGSTVCounter(WIGSTVCounter):
 				__pragma__('opov')
 				if self.options['papers'] == 'transferable':
 					if transferable_votes > surplus:
-						new_value = (ballot.value * surplus) / transferable_ballots
+						new_value = (ballot.value * surplus).to_rational() / transferable_ballots.to_rational()
 					else:
 						new_value = ballot_value
 				else:
-					new_value = (ballot.value * surplus) / total_ballots
+					new_value = (ballot.value * surplus).to_rational() / total_ballots.to_rational()
 				
 				new_parcel.append((ballot, new_value))
 				__pragma__('noopov')