2016 Update

Task/Random-numbers/Elixir/random-numbers-1.elixir

@@ -0,0 +1,16 @@
+defmodule Random do
+  def normal(mean, sd) do
+    {a, b} = {:rand.uniform, :rand.uniform}
+    mean + sd * (:math.sqrt(-2 * :math.log(a)) * :math.cos(2 * :math.pi * b))
+  end
+end
+
+std_dev = fn (list) ->
+            mean = Enum.sum(list) / length(list)
+            sd = Enum.reduce(list, 0, fn x,acc -> acc + (x-mean)*(x-mean) end) / length(list)
+                 |> :math.sqrt
+            IO.puts "Mean: #{mean},\tStdDev: #{sd}"
+          end
+
+xs = for _ <- 1..1000, do: Random.normal(1.0, 0.5)
+std_dev.(xs)

Task/Random-numbers/Elixir/random-numbers-2.elixir

@@ -0,0 +1,2 @@
+xs = for _ <- 1..1000, do: 1.0 + :rand.normal * 0.5
+std_dev.(xs)

Task/Random-numbers/Elixir/random-numbers.elixir

@@ -1,12 +0,0 @@
-defmodule Random do
-  def init() do
-    :random.seed(:erlang.now())
-  end
-  def normal(mean, sd) do
-    {a, b} = {:random.uniform(), :random.uniform()}
-    mean + sd * (:math.sqrt(-2 * :math.log(a)) * :math.cos(2 * :math.pi * b))
-  end
-end
-
-Random.init()
-xs = for _ <- 1..1000, do: Random.normal(1.0, 0.5)