71 lines
2.3 KiB
Python
71 lines
2.3 KiB
Python
# pyRCV2: Preferential vote counting
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# Copyright © 2020 Lee Yingtong Li (RunasSudo)
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#
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# This program is free software: you can redistribute it and/or modify
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# it under the terms of the GNU Affero General Public License as published by
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# the Free Software Foundation, either version 3 of the License, or
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# (at your option) any later version.
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#
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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# GNU Affero General Public License for more details.
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#
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# You should have received a copy of the GNU Affero General Public License
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# along with this program. If not, see <https://www.gnu.org/licenses/>.
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from pyRCV2.model import Ballot, Candidate, Election
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from pyRCV2.numbers import Num
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class BLTException(Exception):
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pass
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def readBLT(data):
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lines = data.split('\n')
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election = Election()
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# Read first line
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num_candidates = int(lines[0].strip().split(' ')[0])
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election.seats = int(lines[0].strip().split(' ')[1])
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# Read withdrawn candidates
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withdrawn = []
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i = 1
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if lines[i].strip().startswith('-'):
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withdrawn.extend([int(x[1:]) - 1 for x in lines[i].strip().split(' ')])
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i += 1
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# Read ballots
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ballot_data = []
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for j in range(i, len(lines)):
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if lines[j].strip() == '0': # End of ballots
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break
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bits = lines[j].strip().split(' ')
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preferences = [int(x) - 1 for x in bits[1:] if x != '0']
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ballot_data.append((bits[0], preferences))
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# Read candidates
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for k in range(j + 1, j + 1 + num_candidates):
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election.candidates.append(Candidate(lines[k].strip()[1:-1]))
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# Read name
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if j + 1 + num_candidates < len(lines):
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election.name = lines[j + 1 + num_candidates].strip()[1:-1]
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# Any additional data?
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if len(lines) > j + 2 + num_candidates and len(lines[j + 2 + num_candidates].strip()) > 0:
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raise BLTException('Unexpected data at end of BLT file')
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if len(lines) > j + 3 + num_candidates:
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raise BLTException('Unexpected data at end of BLT file')
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# Process ballots
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for ballot in ballot_data:
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preferences = [election.candidates[x] for x in ballot[1]]
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election.ballots.append(Ballot(Num(ballot[0]), preferences))
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# Process withdrawn candidates
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election.withdrawn = [election.candidates[x] for x in withdrawn]
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return election
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