RosettaCodeData/Task/Sparkline-in-unicode/Haskell/sparkline-in-unicode-2.hs
2023-07-01 13:44:08 -04:00

37 lines
913 B
Haskell

import Data.Bifunctor (bimap)
import Data.List (findIndex)
import Data.List.Split (splitOneOf)
import Data.Maybe (maybe)
------------------------ SPARK LINE ----------------------
sparkLine :: [Float] -> String
sparkLine [] = ""
sparkLine xxs@(x : xs) =
fmap
( maybe '█' ("▁▂▃▄▅▆▇" !!)
. flip findIndex lbounds
. (<)
)
xxs
where
(mn, mx) = foldr (bimap . min <*> max) (x, x) xs
w = (mx - mn) / 8
lbounds = (mn +) . (w *) <$> [1 .. 7]
--------------------------- TEST -------------------------
main :: IO ()
main =
mapM_ putStrLn $
sparkLine . parseFloats
<$> [ "0, 1, 19, 20",
"0, 999, 4000, 4999, 7000, 7999",
"1 2 3 4 5 6 7 8 7 6 5 4 3 2 1",
"1.5, 0.5 3.5, 2.5 5.5, 4.5 7.5, 6.5"
]
parseFloats :: String -> [Float]
parseFloats =
fmap read
. filter (not . null)
. splitOneOf " ,"