Читать книгу Informatics and Machine Learning. From Martingales to Metaheuristics онлайн

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----------------------- prog1.py addendum 2 ------------------ def shannon( probs ): shannon_entropy = 0 numterms = len(probs) print(numterms) for index in range(0, numterms): print(probs[index]) shannon_entropy += probs[index]*math.log(probs[index]) shannon_entropy = -shannon_entropy print(shannon_entropy) return shannon_entropy shannon(probs) value = shannon(probs) print(value) -------------------- end prog1.py addendum 2 -----------------

If we do another set of observations, getting counts on the different rolls, we then need to repeat the process of converting those counts to frequencies… so it is time to elevate the count‐to‐frequency computation to subroutine status as well, as is done next. The standard syntactical structure for defining a subroutine in Python is hopefully starting to become apparent (more detailed Python notes are in ssss1).

------------------- prog1.py addendum 3 ---------------------- def count_to_freq( counts ): numterms = len(counts) total_count=0 for index in range(0,numterms): total_count+=counts[index] probs = counts # to get memory allocation for index in range(0,numterms): probs[index] = counts[index]/total_count return probs probs = count_to_freq(rolls) print(probs) ----------------- end prog1.py addendum 3 --------------------