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Rev 24 Rev 39
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import sys
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import sys
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import math
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import math
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import random
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import random
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fTrace = 1
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fTrace = 1
- 
 
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randcalls = 0
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def trace(s):
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def trace(s):
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    global fTrace
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    global fTrace
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    if fTrace: print s
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    if fTrace: print s
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    return
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    return
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def findWinner(winners, losers, tally, quota, nWinners):
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def findWinner(winners, losers, tally, quota, nWinners):
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    global randcalls
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    cWin = quota       # number of votes for highest winner
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    lWin = []          # list of candidates with highest votes
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    for candidate in tally.keys():
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    for c in tally.keys():
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        if candidate not in winners and len(tally[candidate]) >= quota:
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        if c not in losers and c not in winners and len(tally[c]) >= cWin:
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            if len(tally[c]) == cWin:
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                lWin.append(c)
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            else:
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                lWin = [c]
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                cWin = len(tally[c])
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    if len(lWin) == 1:
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            return candidate
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        return lWin[0]
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    elif len(lWin) > 1:
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        trace("\tselecting winning candidate randomly from %s" % lWin)
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        randcalls += 1
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        return random.choice(lWin)
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    # Check to see if only enough candidates remain
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    # Check to see if only enough candidates remain
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    n = 0
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    n = 0
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    last = ""
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    last = ""
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    for candidate in tally.keys():
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    for candidate in tally.keys():
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    if nWinners - len(winners) >= n:
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    if nWinners - len(winners) >= n:
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        return last
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        return last
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    return
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    return
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def redistributeWinner(winner, winners, losers, tally, quota):
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def redistributeWinner(winner, winners, losers, tally, quota):
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    global randcalls
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    excess = len(tally[winner]) - quota
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    excess = len(tally[winner]) - quota
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    if excess <= 0:
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    if excess <= 0:
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        trace("\tno excess ballots to redistribute")
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        trace("\tno excess ballots to redistribute")
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    else:
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    else:
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        trace("\tredistributing %d excess ballot(s) at random from %s" %
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        trace("\tredistributing %d excess ballot(s) at random from %s" %
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              (excess, winner))
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              (excess, winner))
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        while len(tally[winner]) > quota:
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        while len(tally[winner]) > quota:
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            i = int(random.uniform(0, len(tally[winner])))
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            i = int(random.uniform(0, len(tally[winner])))
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            randcalls += 1
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            trace("\trandom choice = ballot %d" % (i+1))
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            trace("\trandom choice = ballot %d" % (i+1))
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            ballot = tally[winner][i]
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            ballot = tally[winner][i]
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            tally[winner] = tally[winner][0:i] + tally[winner][i+1:]
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            tally[winner] = tally[winner][0:i] + tally[winner][i+1:]
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            redistributeBallot(ballot, winner, winners, losers, tally)
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            redistributeBallot(ballot, winner, winners, losers, tally)
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    traceTally(quota, tally)
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    traceTally(quota, tally)
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            break
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            break
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    if ballot:
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    if ballot:
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        trace("\tineffective ballot dropped: %s" % ballot)
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        trace("\tineffective ballot dropped: %s" % ballot)
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def findLoser(losers, winners, tally):
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def findLoser(losers, winners, tally):
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    global randcalls
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    cMin = sys.maxint  # least number of votes for candidate loser
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    cMin = sys.maxint  # least number of votes for candidate loser
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    lMin = []          # list of candidates with least votes
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    lMin = []          # list of candidates with least votes
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    for c in tally.keys():
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    for c in tally.keys():
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        if c not in losers and c not in winners and len(tally[c]) <= cMin:
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        if c not in losers and c not in winners and len(tally[c]) <= cMin:
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            if len(tally[c]) == cMin:
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            if len(tally[c]) == cMin:
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                lMin.append(c)
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                lMin.append(c)
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            else:
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            else:
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                lMin = [c]
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                lMin = [c]
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                cMin = len(tally[c])
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                cMin = len(tally[c])
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    trace("\nELIMINATING LOW CANDIDATE RANDOMLY FROM %s" % lMin)
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    if len(lMin) == 0:
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    if len(lMin) == 0:
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        return None
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        return None
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    elif len(lMin) == 1:
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        return lMin[0]
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    else:
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    else:
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        trace("\teliminating low candidate randomly from %s" % lMin)
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        randcalls += 1
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        return random.choice(lMin)
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        return random.choice(lMin)
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def redistributeLoser(loser, losers, winners, tally, quota):
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def redistributeLoser(loser, losers, winners, tally, quota):
95 
    excess = len(tally[loser])
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    excess = len(tally[loser])
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    if excess <= 0:
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    if excess <= 0:
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#   else:
 142 
#   else:
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#       eliminate lowest ranking candidate
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#       eliminate lowest ranking candidate
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#       redistribute wasted votes to next priority candidate
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#       redistribute wasted votes to next priority candidate
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#
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#
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def dotally(nWinners, ballots):
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def dotally(nWinners, ballots):
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 147 
    global randcalls
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    nBallots = len(ballots)
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    nBallots = len(ballots)
128 
    quota = int(math.ceil((nBallots + 1.0)/(nWinners + 1)))
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    quota = int(math.ceil((nBallots + 1.0)/(nWinners + 1)))
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    trace("INPUT SUMMARY")
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    trace("INPUT SUMMARY")
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    trace("\t%d ballots" % nBallots)
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    trace("\t%d ballots" % nBallots)
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                trace("\nELIMINATED: %s" % loser)
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                trace("\nELIMINATED: %s" % loser)
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                redistributeLoser(loser, losers, winners, tally, quota)
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                redistributeLoser(loser, losers, winners, tally, quota)
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            else:
 182 
            else:
162 
                trace("Not enough chosen candidates to fill all positions")
 183 
                trace("Not enough chosen candidates to fill all positions")
163 
                break
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                break
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 185 
    trace("\nNumber of random choices made: %d" % randcalls)
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165 
    return winners
 187 
    return winners
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