如何在Spark中转置数据帧？

import org.apache.spark.sql.functions._
import org.apache.spark.sql.DataFrame

val df = spark.createDataFrame(Seq(
  ("Alice", "Math", 90),
  ("Alice", "Science", 85),
  ("Bob", "Math", 75),
  ("Bob", "Science", 80),
  ("Charlie", "Math", 95),
  ("Charlie", "Science", 92)
)).toDF("Name", "Subject", "Score")

val transposedDF = df.groupBy("Name").pivot("Subject").agg(first("Score"))

transposedDF.show()