Data commit

Task/Ramanujans-constant/Haskell/ramanujans-constant.hs

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+import Control.Monad (forM_)
+import Data.Number.CReal (CReal, showCReal)
+import Text.Printf (printf)
+
+ramfun :: CReal -> CReal
+ramfun x = exp (pi * sqrt x)
+
+-- Ramanujan's constant.
+ramanujan :: CReal
+ramanujan = ramfun 163
+
+-- The last four Heegner numbers.
+heegners :: [Int]
+heegners = [19, 43, 67, 163]
+
+-- The absolute distance to the nearest integer.
+intDist :: CReal -> CReal
+intDist x = abs (x - fromIntegral (round x))
+
+main :: IO ()
+main = do
+  let n = 35
+  printf "Ramanujan's constant: %s\n\n" (showCReal n ramanujan)
+  printf "%3s %34s%20s%s\n\n" " h " "e^(pi*sqrt(h))" "" " Dist. to integer"
+  forM_ heegners $ \h ->
+    let r = ramfun (fromIntegral h)
+        d = intDist r
+    in printf "%3d %54s %s\n" h (showCReal n r) (showCReal 15 d)