11 lines
221 B
Text
11 lines
221 B
Text
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func entropy(s) {
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var counts = Hash.new;
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s.each { |c| counts{c} := 0 ++ };
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var len = s.len;
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[0, counts.values.map {|count|
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var freq = count/len; freq * freq.log2 }...
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]«-»;
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}
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say entropy("1223334444");
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