In the snippet below, graph.edges.groupBy[VertexId](f1).foreach { edgesBySrc => { f2(edgesBySrc).foreach { vertexId => { *println(vertexId)* } } } }
"f1" is a function that determines how to group the edges (in my case it groups by source vertex) "f2" is another function that does some computation on the edges. It returns an iterable (Iterable[VertexId]). *Questions:* 1. The problem is that "println(vertexId)" doesn't printing anything. I have made sure that "f2" doesn't return an empty iterable. I am not sure what I am missing here. 2. I am assuming that "f2" is called for each group in parallel. Is this correct? If not, what is the correct way to operate on each group in parallel? Thanks! -- View this message in context: http://apache-spark-user-list.1001560.n3.nabble.com/RDD-groupBy-tp21773.html Sent from the Apache Spark User List mailing list archive at Nabble.com. --------------------------------------------------------------------- To unsubscribe, e-mail: user-unsubscr...@spark.apache.org For additional commands, e-mail: user-h...@spark.apache.org