Developing Evaluator Similar product template

[Dennis Honders]

Hi,

I'm currently working on an Evaluator for the Similar product template. I'm
not a Scala expert.

I followed the Classification Quickstart which is used for the Evaluator
tutorial. http://predictionio.incubator.apache.org/evaluation/paramtuning/

A RDD of LabeldPoint is used to retrieve data.

   - val labeledPoints: RDD[LabeledPoint] = eventsDb.aggregateProperties(...

The Similar product template retrieves like:

   - val usersRDD: RDD[(String, User)] = PEventStore.aggregateProperties(...
   - val itemsRDD: RDD[(String, Item)] = PEventStore.aggregateProperties(
   - val viewEventsRDD: RDD[ViewEvent] = PEventStore.find(

According to the docs, the above should be the same?

}.cache()
    // End of reading from data store

    // K-fold splitting
    val evalK = dsp.evalK.get
    val indexedPointsUsers: RDD[((String, User), Long)] =
usersRDD.zipWithIndex()
    val indexedPointsItems: RDD[((String, Item), Long)] =
itemsRDD.zipWithIndex()
    val indexedPointsView: RDD[(ViewEvent, Long)] =
viewEventsRDD.zipWithIndex()

    (0 until evalK).map { idx =>
      val trainingPointsUsers = indexedPointsUsers.filter(_._2 % evalK !=
idx).map(_._1)
      val testingPointsUsers = indexedPointsUsers.filter(_._2 % evalK ==
idx).map(_._1)

      val trainingPointsItems = indexedPointsItems.filter(_._2 % evalK !=
idx).map(_._1)
      val testingPointsItems = indexedPointsItems.filter(_._2 % evalK ==
idx).map(_._1)

      val trainingPointsView = indexedPointsView.filter(_._2 % evalK !=
idx).map(_._1)
      val testingPointsView = indexedPointsView.filter(_._2 % evalK ==
idx).map(_._1)

      (
        new TrainingData(trainingPointsUsers, trainingPointsItems,
trainingPointsView),
        new EmptyEvaluationInfo(),
        testingPointsUsers.map {
          p => (new Query(p.features(0), p.features(1), p.features(2)), new
ActualResult(p.label))
        }
      )
    }


class TrainingData(val users: RDD[(String, User)], val items: RDD[(String,
Item)], val viewEvents: RDD[ViewEvent]) extends Serializable {
  override def toString = {
      s"users: [${users.count()} (${users.take(2).toList}...)]" +
      s"items: [${items.count()} (${items.take(2).toList}...)]" +
      s"viewEvents: [${viewEvents.count()}]
(${viewEvents.take(2).toList}...)"
  }
}


What happens at this part? The red marks correspondend to 'Cannot resolve
symbol *'

   -  testingPointsUsers.map {
             p => (new Query(p.features(0), p.features(1), p.features(2)),
   new ActualResult(p.label))
           }




Thanks in advance,

Dennis