9 lines
202 B
Ruby
9 lines
202 B
Ruby
def entropy(s)
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counts = Hash.new(0)
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s.each_char { |c| counts[c] += 1 }
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counts.values.reduce(0) do |entropy, count|
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freq = count / s.length.to_f
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entropy - freq * Math.log2(freq)
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end
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end
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