12 lines
207 B
Ruby
12 lines
207 B
Ruby
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def entropy(s)
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counts = s.chars.tally
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leng = s.length.to_f
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counts.values.reduce(0) do |entropy, count|
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freq = count / leng
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entropy - freq * Math.log2(freq)
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end
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end
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p entropy("1223334444")
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