我是Scala的新手。我有一个文本文件，该文件只有一行，文件单词之间用分号（;）分隔。我想提取每个单词，删除空格，将所有都转换为小写，然后根据每个单词的索引调用它们。以下是我的处理方法：
newListUpper2.txt contains (Bed; chairs;spoon; CARPET;curtains )
val file = sc.textFile("myfile.txt")
val lower = file.map(x=>x.toLowerCase)
val result = lower.flatMap(x=>x.trim.split(";"))
result.collect.foreach(println)
下面是我执行代码时REPL的副本
scala> val file = sc.textFile("newListUpper2.txt")
file: org.apache.spark.rdd.RDD[String] = newListUpper2.txt MapPartitionsRDD[5] at textFile at
<console>:24
scala> val lower = file.map(x=>x.toLowerCase)
lower: org.apache.spark.rdd.RDD[String] = MapPartitionsRDD[6] at map at <console>:26
scala> val result = lower.flatMap(x=>x.trim.split(";"))
result: org.apache.spark.rdd.RDD[String] = MapPartitionsRDD[7] at flatMap at <console>:28
scala> result.collect.foreach(println)
bed
chairs
spoon
carpet
curtains
scala> result(0)
<console>:31: error: org.apache.spark.rdd.RDD[String] does not take parameters
result(0)
不修剪结果，然后将索引作为参数传递以获得该索引处的单词会产生错误。如果我将每个单词的索引作为参数传递，我的预期结果应如下所示
result(0)= bed
result(1) = chairs
result(2) = spoon
result(3) = carpet
result(4) = curtains
我究竟做错了什么？。
newListUpper2.txt contains (Bed; chairs;spoon; CARPET;curtains )
val file = sc.textFile("myfile.txt")
val lower = file.map(x=>x.toLowerCase)
val result = lower.flatMap(x=>x.trim.split(";")) // x = `bed; chairs;spoon; carpet;curtains` , x.trim does not work. trim func effective for head and tail only
result.collect.foreach(println)
试试看：
val result = lower.flatMap(x=>x.split(";").map(x=>x.trim))
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