srowen commented on a change in pull request #25178: [SPARK-28421][ML] SparseVector.apply performance optimization URL: https://github.com/apache/spark/pull/25178#discussion_r304941428
########## File path: mllib-local/src/main/scala/org/apache/spark/ml/linalg/Vectors.scala ########## @@ -603,6 +603,19 @@ class SparseVector @Since("2.0.0") ( private[spark] override def asBreeze: BV[Double] = new BSV[Double](indices, values, size) + override def apply(i: Int): Double = { + if (i < 0 || i >= size) { + throw new IndexOutOfBoundsException(s"Index $i out of bounds [0, $size)") + } + + if (indices.isEmpty || i < indices(0) || i > indices(indices.length - 1)) { Review comment: Yes you need the check that the index is < 0 or >= length, keep that. But `binarySearch` already handles the case that the query index is >= 0 but before the first actual index: ``` scala> java.util.Arrays.binarySearch(Array(2,3), 1) res0: Int = -1 scala> java.util.Arrays.binarySearch(Array(2,3), 4) res1: Int = -3 ``` Why repeat that part? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org