Scala 入门笔记 - (Map)

val map1 = Map("scala" -> 1, "java" -> 2, "C" -> 3)

val map2 = Map(("scala", 1), ("java", 2), ("C" -> 3))

map1.getOrElse("C#", -1) // 如果没有要取的值，这个方法不会报错，而是返回-1

　　

元组

val t = ("scala", 100L, 3.14, ("spark", 1))

t ._1  // 访问元组中对应的值  - scala




val t, (a, b, c, d) = ("scala", 100L, 3.14, ("spark", 1))

// a 就是对应scala

　　

zip 方法

scala> val arr1 = Array("aaa", "bbb", "ccc")
arr1: Array[String] = Array(aaa, bbb, ccc)

scala> val arr2 = Array(1, 2, 3, 4)
arr2: Array[Int] = Array(1, 2, 3, 4)

scala> arr1 zip arr2
res62: Array[(String, Int)] = Array((aaa,1), (bbb,2), (ccc,3))

scala> arr2 zip arr1
res63: Array[(Int, String)] = Array((1,aaa), (2,bbb), (3,ccc))