Scala：值拆分不是char的成员

Scala: value split is not a member of char

提问by Brigitte

I am trying to write word count program in Scala. I'm using a string "file":

我正在尝试在 Scala 中编写字数统计程序。我正在使用一个字符串"file"：

file.map( _.split(" ")).flatMap(word => (word, 1)).reduceByKey( _ + _ )

It is keep saying that:

一直在说：

value split is not a member of Char

value split 不是 Char 的成员

Can't figure out how to solve it!

想不通怎么解决！

回答by Dave Swartz

When you call mapon a Stringit is wrapped with WrappedStringwhich extends AbstractSeq[Char]. Therefore, when you call mapit is as if you are doing so on a Seqof Charnot a Seqof String.

当您调用mapa 时，String它被包裹在WrappedStringwhich extends 中AbstractSeq[Char]。因此，当您调用map它时，就好像您是在 a Seqof Charnot a Seqof上这样做一样String。

See the link below for the code https://github.com/scala/scala/blob/v2.10.2/src/library/scala/collection/immutable/WrappedString.scala

代码见下方链接https://github.com/scala/scala/blob/v2.10.2/src/library/scala/collection/immutable/WrappedString.scala

The code below splits by whitespace and returns the size, a word counter.

下面的代码按空格分割并返回大小，一个字计数器。

val file = "Some test data"
file.split("\s+").size

To get a count of the number of times each word in the string appears.

获取字符串中每个单词出现的次数的计数。

val file = "Some test data test"
println(file.split("\s+").toList.groupBy(w => w).mapValues(_.length))

回答by Brigitte

I found out that the code is perfect! Just because I was running it on Spark, the answer was kept in lazy RDD file that I needed to collect it somehow. Therefore, I saved it to a text file and problem solved! Here is the code:

我发现代码是完美的！仅仅因为我在 Spark 上运行它，答案就保存在我需要以某种方式收集它的惰性 RDD 文件中。因此，我将其保存到文本文件中，问题解决了！这是代码：

file.flatMap(line=>line.split(" ")).map(w=>(w,1)).reduceByKey(+).saveAsTextFile("OUT.txt")

file.flatMap(line=>line.split(" ")).map(w=>(w,1)).reduceByKey( +).saveAsTextFile("OUT.txt")

Thanks.

谢谢。