felixcheung
/ sparkPercentile.scala
Last active
March 28, 2018 08:26
Spark compute percentile with RDD in Scala
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| /** | |
| * compute percentile from an unsorted Spark RDD | |
| * @param data: input data set of Long integers | |
| * @param tile: percentile to compute (eg. 85 percentile) | |
| * @return value of input data at the specified percentile | |
| */ | |
| def computePercentile(data: RDD[Long], tile: Double): Double = { | |
| // NIST method; data to be sorted in ascending order | |
| val r = data.sortBy(x => x) | |
| val c = r.count() |