Github user setjet commented on a diff in the pull request: https://github.com/apache/spark/pull/18113#discussion_r118843548 --- Diff: sql/core/src/main/scala/org/apache/spark/sql/execution/aggregate/typedaggregators.scala --- @@ -99,3 +97,67 @@ class TypedAverage[IN](val f: IN => Double) extends Aggregator[IN, (Double, Long toColumn.asInstanceOf[TypedColumn[IN, java.lang.Double]] } } + +class TypedMinDouble[IN](val f: IN => Double) extends Aggregator[IN, Double, Double] { + override def zero: Double = Double.PositiveInfinity --- End diff -- @viirya I just had a go at your suggestion, but it seems to be more complicated than anticipated. Spark performs some implicit casts (I think as part of Catalyst) between `java.lang.Double` and `scala.Double`, causing a nullpointer: `java.lang.NullPointerException at scala.Predef$.Double2double(Predef.scala:365!` I am not sure if this method is feasible. Sample of the `merge` function: `override def merge(b1: java.lang.Double, b2: java.lang.Double): java.lang.Double = java.lang.Math.min(b1, b2)`
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. --- --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org