Random numbers: Difference between revisions

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 =={{header|Scala}}==
+===One liner===
 <lang scala>List.fill(1000)(1.0 + 0.5 * scala.util.Random.nextGaussian)</lang>
+===Academic===
+<lang scala>val distrubution = {
+  def randomNormal = 1.0 + 0.5 * scala.util.Random.nextGaussian
+  def normalDistribution(a: Double): Stream[Double] = a #:: normalDistribution(randomNormal)
+  normalDistribution(randomNormal)
+}
+/*
+ * Let's test it
+ */
+def calcAvgAndStddev[T](ts: Iterable[T])(implicit num: Fractional[T]): (T, Double) = {
+  def avg(ts: Iterable[T])(implicit num: Fractional[T]): T = {
+    num.div(ts.sum, num.fromInt(ts.size)) // Leaving with type of function T
+  }
+  def mean = avg(ts)
+  def stdDev = // Root of mean diffs
+    math.sqrt(num.toDouble(
+      ts.foldLeft(num.zero)((b, a) =>
+        num.plus(b, num.times(num.minus(a, mean), num.minus(a, mean))))) / ts.size)
+  (mean, stdDev)
+}
+println(calcAvgAndStddev(distrubution.take(1000))) // e.g. (1.0061433267806525,0.5291834867560893)</lang>
 =={{header|Scheme}}==