scala.collection.parallel implementations of Akka's Pi Tutorial

PiParallel.scala

// Akka's Pi Tutorial implemented with scala.collection.parallel

object PiParallel extends App {
  import scala.collection.GenSeq
  
  val seqRng = Range(0, 10000 * 10000).view
  val parRng = Range(0, 10000 * 10000).par.view
  
  def calculatePi(rng: GenSeq[Int]): Double =
    rng.map{i => 4.0 * (1 - (i % 2) * 2) / (2 * i + 1)}.sum;
    
  def calculatePiInline: Double = {
    var sum = 0.0
    var i = 0;
    while (i < 10000 * 10000) {
      sum += 4.0 * (1 - (i % 2) * 2) / (2 * i + 1)
      i += 1
    }
    sum
  }

  println("collection.parallel.availableProcessors == "+collection.parallel.availableProcessors)
  timeKeep(calculatePi(seqRng), "Sequential:")
  timeKeep(calculatePi(parRng), "Parallel:")
  timeKeep(calculatePiInline, "Inline(Seq):")
  
  def timeKeep[A <: AnyRef](calcPi: => Double, msg: String) {
    println(msg)
    val t1 = System.nanoTime
    val pi = calcPi
    val t2 = System.nanoTime
    println(
      "\tPi estimate: \t\t%s\n\tCalculation time: \t%s millis"
      .format(pi, (t2 - t1) / 1000000))
  }
}