spark--PageRank

package spark1

import org.apache.spark.{SparkConf, SparkContext}

object test {

def main(args: Array[String]): Unit = {
val nums = 2
val conf = new SparkConf().setAppName("PageRank").setMaster("local")
val sc = new SparkContext(conf)
val links = sc.parallelize(Array(('A', Array('D')), ('B', Array('A')), ('C', Array('A', 'B')), ('D', Array('A', 'C')))).cache()
var ranks = sc.parallelize(Array(('A', 1.0), ('B', 1.0), ('C', 1.0), ('D', 1.0)))
for (i <- 1 to nums) {
val contribs = links.join(ranks).flatMap({
case (url, (links, rank)) => links.map(dest => (dest, rank / links.size))
})
ranks = contribs.reduceByKey(_+_).mapValues(0.15+0.85*_)
}
ranks.foreach(println)
}

}

(B,0.394375)
(A,1.3081249999999998)
(C,0.575)
(D,1.7224999999999997)