#!/home/98/46/2924698/bin/python2.3
from math import log, floor, ceil
from operator import mul, add
fac = lambda N: reduce(mul, range(1,N+1), 1)
perm = lambda N,M: fac(M)/fac(M-N)
comb = lambda N,M: perm(N,M)/fac(N)
mult_vote = lambda N,M: reduce(add, [comb(i,M) for i in range(1,N+1)], 1)
rank_vote = lambda N,M: reduce(add, [perm(i,M) for i in range(1,N+1)], 1)
sing_vote = lambda N: N+1
SD = lambda n,d: d*ceil(log(n)/log((2**d)/2))
def report(data, alphabet_size):
possible, comment = [], ''
for line in data.split('\n'):
if not line.strip(): continue
if line.startswith('#'):
comment += line[1:]
continue
opts = line.split()
type_ = opts[0].upper()
if type_=='SINGLE': possible.append(sing_vote(int(opts[1])))
elif type_=='MULTI': possible.append(mult_vote(*map(int, opts[1:3])))
elif type_=='RANKED': possible.append(rank_vote(*map(int, opts[1:3])))
print comment.lstrip()
total = reduce(mul,possible)
print total, "distinct votes are possible"
entropy = ceil(log(total)/log(2))
print "Optimal encoding is approximately: %d bits" % entropy
logs = [log(p)/log(2) for p in possible]
per_contest = reduce(add, map(ceil, logs))
print "Contests at bit-boundaries, approx: %d bits" % per_contest
d = ceil(log(alphabet_size)/log(2))
self_delim = [SD(n,d) for n in possible]
per_delim = reduce(add, map(ceil, self_delim))
print "Self-delimited (%d char symbology): %d bits " \
% (alphabet_size, per_delim)
print
print "Vote Space Optimal Self-Delim"
print "---------- ------- ----------"
for _ in zip(possible, map(ceil,logs), map(ceil,self_delim)):
print "%7d %2d %2d" % _
import cgitb; cgitb.enable()
import cgi
init = """# Election summary for OVC demo (write-ins count as candidate)
single 8 # Prez, 7 candidates plus write-in
single 8 # Senator
single 3 # Representative
single 3 # Treasurer
single 4 # AG
single 3 # Edu Commis
single 4 # State Senate
single 3 # Assembly
single 2 # Transportation initiative
single 2 # health care
single 2 # term limit
multi 3 10 # Cat Catcher
ranked 8 8 # County Commissioner
"""
form = cgi.FieldStorage()
data = form.getvalue('data',init)
alphabet = form.getvalue('alphabet',8)
print "content-type: text/html"
print
print """
Election Entropy Calculator
Election Entropy
Configuration Sample
#TYPE M of N # (optional) comments on contest
%s
Election Data to Analyze
Report
""" % (init, data, alphabet)
report(data, int(alphabet))
print "
"