take top N after groupBy and treat them as RDD

Question

I\'d like to get top N items after groupByKey of RDD and convert the type of topNPerGroup(in the below) to RDD[(String, Int)]

Answer 1

Your question is a little confusing, but I think this does what you're looking for:

val flattenedTopNPerGroup = 
    topNPerGroup.flatMap({case (key, numbers) => numbers.map(key -> _)})

and in the repl it prints out what you want:

flattenedTopNPerGroup.collect.foreach(println)
(foo,3)
(foo,2)
(bar,6)
(bar,5)