[SPARK-20574] Allow Bucketizer to handle non-Double column

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.1.0
• Fix Version/s: 2.2.0
• Component/s: ML
• Assignee: Wayne Zhang
• Reporter: Wayne Zhang
• Shepherd: Yanbo Liang
• Created: 03/May/17 05:59
• Updated: 05/May/17 02:30
• Resolved: 05/May/17 02:30

Description

Bucketizer currently requires input column to be Double, but the logic should work on any numeric data types. Many practical problems have integer/float data types, and it could get very tedious to manually cast them into Double before calling bucketizer. This transformer could be extended to handle all numeric types.

The example below shows failure of Bucketizer on integer data.

val splits = Array(-3.0, 0.0, 3.0)
val data: Array[Int] = Array(-2, -1, 0, 1, 2)
val expectedBuckets = Array(0.0, 0.0, 1.0, 1.0, 1.0)
val dataFrame = data.zip(expectedBuckets).toSeq.toDF("feature", "expected")
val bucketizer = new Bucketizer()
  .setInputCol("feature")
  .setOutputCol("result")
  .setSplits(splits)
bucketizer.transform(dataFrame)  

java.lang.IllegalArgumentException: requirement failed: Column feature must be of type DoubleType but was actually IntegerType.

Issue Links

• links to: [Github] Pull Request #17840 (actuaryzhang)