result.sortBy(t => t._2).take(10)
cmd演示：
val list = List(("zhangsan",20),("lisi",9),("wangwu",33))
list.sortBy(t => t._2).takeRight(1) //表示从右边开始取几条
对RDD进行操作：
result.sortBy(t => t._2,ascending=false).take(10)
result.sortBy(t => t._2 * -1).take(10)
result.map( t => t.swap).sortByKey(ascending=false).map(t => t.swap).take(10)
cmd演示：
val list = List(("zhangsan",20),("lisi",9),("wangwu",33))
list.sortBy(t => t._2).takeRight(1) //表示从右边开始取几条
对RDD进行操作：
result.sortBy(t => t._2,ascending=false).take(10)
result.sortBy(t => t._2 * -1).take(10)
result.map( t => t.swap).sortByKey(ascending=false).map(t => t.swap).take(10)
result.map(t => t.swap).top(5).map(t => t.swap).take(10)
----------------------------------------------------------------------------------------------------------------------------------自定义排序器
top(num: Int)(implicit ord: Ordering[T])
result.top(10)(ord = new scala.math.Ordering[(String,Int)](){
override def compare(x:(String,Int),y:(String,Int)) ={
val t1 = x._2.compare(y._2)
if(t1 != 0){
t1
}else{
val t2 = x._1.compare(y._1)
t2
}
}
})
基于top函数实现获取出现次数最少的前10个单词
result.top(10)(ord = new scala.math.Ordering[(String,Int)](){
override def compare(x:(String,Int),y:(String,Int)) ={
val t1 = x._2.compare(y._2)
if(t1 != 0){
t1 * -1
}else{
val t2 = x._1.compare(y._1)
t2 * -1
}
}
})