25 lines
727 B
Haskell
25 lines
727 B
Haskell
module Main where
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import Control.Monad
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import Data.List
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import Data.Monoid
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import Text.Printf
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entropy :: (Ord a) => [a] -> Double
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entropy = sum
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. map (\c -> (c *) . logBase 2 $ 1.0 / c)
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. (\cs -> let { sc = sum cs } in map (/ sc) cs)
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. map (fromIntegral . length)
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. group
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. sort
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fibonacci :: (Monoid m) => m -> m -> [m]
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fibonacci a b = unfoldr (\(a,b) -> Just (a, (b, a <> b))) (a,b)
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main :: IO ()
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main = do
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printf "%2s %10s %17s %s\n" "N" "length" "entropy" "word"
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zipWithM_ (\i v -> let { l = length v } in printf "%2d %10d %.15f %s\n"
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i l (entropy v) (if l > 40 then "..." else v))
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[1..38::Int]
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(take 37 $ fibonacci "1" "0")
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