1. Import the graphx related classes:

        scala> import org.apache.spark.graphx._

2. Load the edges from Amazon S3:

        scala> val edgesFile = sc.textFile(
          "s3a://com.infoobjects.wiki/links",20)

3. Flatten and convert edgesFile into an RDD of link1, link2 format, and then convert it into an RDD of Edge objects:

        scala> val edges = edgesFile.flatMap { line =>
   val links = line.split("\W+")
   val from = links(0)
     val to = links.tail
   for ( link <- to) yield (from,link)
    }.map( e => Edge(e._1.toLong,e._2.toLong,1))

4.  Load the edges from Amazon S3:

        scala> val verticesFile = sc.textFile
          ("s3a://com.infoobjects.wiki/nodes",20)

5. Provide an index to the vertices, and then swap it to make it in the (index, title) format:

        scala> val vertices = verticesFile.zipWithIndex.map(_.swap)

6. Create the graph object:

        scala> val graph = Graph(vertices,edges)

7. Run pageRank function, and get the vertices:

        scala> val ranks = graph.pageRank(0.001).vertices

8. As ranks are in the (vertex ID, pagerank) format, swap it to make it in the (pagerank, vertex ID) format:

        scala> val swappedRanks = ranks.map(_.swap)

9. Sort to get the highest ranked pages first:

        scala> val sortedRanks = swappedRanks.sortByKey(false)

10. Get the highest ranked page:

        scala> val highest = sortedRanks.first

11. The preceding command gives the vertex ID, which you still have to look up to see the actual title with the rank. Let's do a join:

        scala> val join = sortedRanks.join(vertices)

12. Sort the joined RDD again after converting from the (vertex ID, (page rank, title)) format to the (page rank, (vertex ID, title)) format:

        scala> val result = join.map ( v => (v._2._1, 
          (v._1,v._2._2))).sortByKey(false)

13. Print the top five ranked pages:

        scala> result.take(5).collect.foreach(println)

14. Here's what the output should be:

    (12406.054646736622,         
    (5302153,United_States'_Country_Reports_on_Human_Rights_Practices))   
    (7925.094429748747,(84707,2007,_Canada_budget)) 
    (7635.6564216408515,(88822,2008,_Madrid_plane_crash)) 
    (7041.479913258444,(1921890,Geographic_coordinates)) 
    (5675.169862343964,(5300058,United_Kingdom's))