使用
window dense_rank() 此案例的函数。
例子：

import org.apache.spark.sql.types._
import org.apache.spark.sql.functions._
import org.apache.spark.sql.expressions._

//sample dataframe
val df=Seq((1,1.01),(1,01.32),(1,1.29),(1,1.03)).toDF("pid","biosver")

val w= Window.orderBy(desc("biosver"))

//if your datatype is string then use casting
val w= Window.orderBy(col("biosver").cast("decimal(10,2)").desc)

df.withColumn("Rank",dense_rank().over(w)).show()

//+---+-------+----+
//|pid|biosver|Rank|
//+---+-------+----+
//|  1|   1.32|   1|
//|  1|   1.29|   2|
//|  1|   1.03|   3|
//|  1|   1.01|   4|
//+---+-------+----+