in src/main/scala/org/apache/spark/sql/datasketches/kll/expressions/KllDoublesSketchExpressions.scala [244:248]
override protected def withNewChildrenInternal(newFirst: Expression,
newSecond: Expression,
newThird: Expression) = {
copy(sketchExpr = newFirst, splitPointsExpr = newSecond, isInclusiveExpr = newThird, isPmf = isPmf)
}