[MAHOUT-497] Matrix get/set causes allocation (?!)

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.4
• Assignee: Unassigned
• Reporter: Ted Dunning
• Created: 08/Sep/10 17:57
• Updated: 31/Oct/10 15:50
• Resolved: 08/Sep/10 20:00

Description

Matrix get and set check the array bounds. But checking the array bounds calls size. But size allocates a small integer
array.

This is evil and KILLs performance.

The first fix is to avoid this in SGD based classifiers. Second will be a real change to the matrix routines to avoid the allocation.