Monte Carlo methods: Difference between revisions

Content added Content deleted

Inline

@@ Line 1,300: / Line 1,300: @@
 monteCarloPi :: Int -> IO Double
-monteCarloPi n = do
+monteCarloPi n =
-  m <- foldM go 0 [1 .. n]
+  foldM go 0 [1 .. n]
-  return (4 * fromIntegral m / fromIntegral n)
+    >>= (pure . (/ fromIntegral n) . (4 *) . fromIntegral)
   where
     rnd = randomRIO (0, 1) :: IO Double
@@ Line 1,308: / Line 1,308: @@
       | 1 > x ** 2 + y ** 2 = succ
       | otherwise = id
-    go a x = do
-      rx <- rnd
+    go a x =
-      ry <- rnd
+      rnd >>= (\rx -> rnd >>= (pure . flip (f rx) a))
-      return $ f rx ry a
 main :: IO ()