Entropie-Berechnung

entropy.py

from math import log

log2 = lambda x: log(x,2)

def entropy(poss):
    a = lambda p: p * log2( 1/p )
    return sum(map(a,poss))


a = (1./6, 1./3, 1./3)
b = (1./2, 1./4, 1./4)
c = (0.01, 0.01, 0.98)


print "E%-65s = %f" % (str(a), entropy(a))
print "E%-65s = %f" % (str(b), entropy(b))
print "E%-65s = %f" % (str(c), entropy(c))