import org.apache.spark.{SparkConf, SparkContext}
/**
* Created by liupeng on 2017/6/16.
*/
object A_reduce {
System.setProperty("hadoop.home.dir","F:\\hadoop-2.6.5")
def main(args: Array[String]): Unit = {
val conf = new SparkConf().setAppName("reduce_test").setMaster("local")
val sc = new SparkContext(conf)
//準備一下資料,有一個集合,通過reduce來進行累加
val list = List(1, 2, 3, 4, 5)
val rdd = sc.parallelize(list)
//reduce它需要兩個參數并傳回一個,來聚合資料集的元素。
val sum = rdd.reduce((x,y) => x + y)
println(sum)
}
}
運作結果: 15