[MAHOUT-1936] FactorMap finds column maximums incorrectly on large data sets

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.13.0
• Fix Version/s: 0.13.0
• Epic Link: Algorithms
• Sprint: 0.14.0 Release
• Assignee: Trevor Grant
• Reporter: Trevor Grant
• Created: 03/Feb/17 16:45
• Updated: 31/Jan/24 22:11
• Resolved: 07/Feb/17 04:08

Description

FactorMap's fit method does not properly find the maximum of the column.

Likely due to an impropper allreduceBlock here
https://github.com/apache/mahout/blob/master/math-scala/src/main/scala/org/apache/mahout/math/algorithms/preprocessing/AsFactor.scala#L40

Also, factorMap in this instance might be more appropriately named "factorMax"

Issue Links

• links to: GitHub Pull Request #278