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要从列表映射的Scala groupBy_Scala - Fatal编程技术网

要从列表映射的Scala groupBy

要从列表映射的Scala groupBy,scala,Scala,我有这样的列表,想把它们转换成地图 val myList = List( "IDENTIFIER, a, b, c", "IDENTIFIER, d, e,f", "INFORMATION, a, b, c", "INFORMATION, d, e, f" ) 预期产出: Map[String,List[String]] = Map(IDENTIFIER -> List(a b c, d e f), INFORMATION -> List(a b

我有这样的列表,想把它们转换成地图

val myList = List(
    "IDENTIFIER, a, b, c", 
    "IDENTIFIER, d, e,f",
    "INFORMATION, a, b, c",
    "INFORMATION, d, e, f"
)
预期产出:

Map[String,List[String]] = Map(IDENTIFIER -> List(a b c, d e f), INFORMATION -> List(a b c, d e f))`
给定列表:

使用,

在Scala中回复:


你需要问一个具体的问题。可能您试图编写代码,但遇到了一个问题。告诉我们您发现的具体问题,以便我们帮助解决。
val myList = List(
    "IDENTIFIER, a, b, c", 
    "IDENTIFIER, d, e, f",
    "INFORMATION, a, b, c",
    "INFORMATION, d, e, f"
)
myList.map(_.split(",")).groupBy(_.head).mapValues(_.map(_.tail.mkString(" ").trim))
scala> myList.map(_.split(",")).groupBy(_.head).mapValues(_.map(_.tail.mkString(" ").trim))
res91: scala.collection.immutable.Map[String,List[String]] = Map(IDENTIFIER -> List(a  b  c, d  e  f), INFORMATION -> List(a
  b  c, d  e  f))

scala>