-def log_pl(frequencies1, frequencies2):
- return sum([frequencies2[l] * log10(frequencies1[l]) for l in frequencies1])
-
-def inverse_log_pl(frequencies1, frequencies2):
- return -log_pl(frequencies1, frequencies2)
-
-def index_of_coincidence(frequencies):
- """Finds the (expected) index of coincidence given a set of frequencies
- """
- return sum([f ** 2 for f in frequencies.values()]) * len(frequencies.keys())
-