Writing a generic mean function in Scala

Question

I\'m trying to write a generic mean function that operates on an Iterable that contains numeric types. It would operate, say, on arrays, as so:

val rand = n         


        

Answer 1

This is quite an old question, but I am basically doing this

def average[A](list: List[Any])(implicit numerics: Numeric[A]): Double = {
  list.map(Option(_)).filter(_.isDefined).flatten match {
    case Nil => 0.0
    case definedElements => numerics.toDouble(list.map(_.asInstanceOf[A]).sum) / definedElements.length.toDouble
  }
}

for a list which might contain null values (I have to keep interoperability with Java). The null elements are not counted towards the average.