sample(withReplacement, fraction, seed) 案例
- 作用:以指定的隨機種子隨機抽樣出數量爲fraction的數據,withReplacement表示是抽出的數據是否放回,true爲有放回的抽樣,false爲無放回的抽樣,seed用於指定隨機數生成器種子。
- 需求:創建一個RDD(1-10),從中選擇放回和不放回抽樣
package com.dark.spark.SparkStudent.Spark_RDD
import org.apache.spark.rdd.RDD
import org.apache.spark.{SparkConf, SparkContext}
object Spark29 extends App {
val config: SparkConf = new SparkConf().setMaster("local[*]").setAppName("WordCount")
val sc = new SparkContext(config)
private val listRDD: RDD[Int] = sc.makeRDD(1 to 10)
private val sampleRDD: RDD[Int] = listRDD.sample(false, 0.4,1)
sampleRDD.collect().foreach(println)
}
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