Question

我有以下功能：

  def isAllDigits(x: String) = x forall Character.isDigit

  def filterNum(x: (Int, String)) : Boolean = {
    accumNum.add(1)
    if(isAllDigits(x._2)) false
    else true
  }

我传入键/值，我想检查值是否为数字。出于某种原因，它正在过滤掉：

res10: Array[(Int, String)] = Array((1,18964), (2,39612), (3,1), (4,""), (5,""), (6,""), (7,""), (8,""), (9,1), (10,""))

但允许这样：

res9: Array[(Int, String)] = Array((18,1000.0), (22,23.99), (18,1001.0), (22,23.99), (18,300.0), (22,23.99), (18,300.0), (22,23.99), (18,300.0), (22,23.99))

.isDigit只允许双打吗？但我很困惑为什么当x是（Int，String）时传入的double / int被视为一个字符串。

编辑：我在Spark中使用此函数具有以下内容：

val numFilterRDD = numRDD.filter(filterNum)

numRDD.take（）示例：

res11: Array[(Int, String)] = Array((1,18964), (2,39612), (3,1), (4,""), (5,""), (6,""), (7,""), (8,""), (9,1), (10,""), (11,""), (16,""), (18,1000.0), (19,""), (20,""), (21,""), (22,23.99), (23,""), (24,""), (25,""))

Answer 1

问题是你是分别运行每个角色。因此，在double的情况下，它会检查小数，并且它本身不是数字：

Character.isDigit('.') //false

您最好使用正则表达式。

x matches """^\d+(\.?\d+)$"""

仅数字的Scala函数过滤字段

1 个答案: