更新时间:2023-02-19 15:23:50
填充:返回一个新的DataFrame来替换其中的null或NaN值 具有值的数字列.
Fill: Returns a new DataFrame that replaces null or NaN values in numeric columns with value.
两件事:
失败,将Null替换为填充/文本:
scala> a.show
+----+---+
| f1| f2|
+----+---+
|null| AA|
| 12| BB|
+----+---+
scala> a.na.fill("Anonymous", Seq("f1")).show
+----+---+
| f1| f2|
+----+---+
|null| AA|
| 12| BB|
+----+---+
工作示例-对所有数字使用空值:
scala> a.show
+----+---+
| f1| f2|
+----+---+
|null| AA|
| 12| BB|
+----+---+
scala> a.na.fill(1, Seq("f1")).show
+---+---+
| f1| f2|
+---+---+
| 1| AA|
| 12| BB|
+---+---+
失败示例(空字符串而不是空):
scala> b.show
+---+---+
| f1| f2|
+---+---+
| | AA|
| 12| BB|
+---+---+
scala> b.na.fill(1, Seq("f1")).show
+---+---+
| f1| f2|
+---+---+
| | AA|
| 12| BB|
+---+---+
案例声明修复示例:
scala> b.show
+---+---+
| f1| f2|
+---+---+
| | AA|
| 12| BB|
+---+---+
scala> b.select(when(col("f1") === "", "Anonymous").otherwise(col("f1")).as("f1"), col("f2")).show
+---------+---+
| f1| f2|
+---------+---+
|Anonymous| AA|
| 12| BB|
+---------+---+