[MATH-951] Patch: Faster implementation of double org.apache.commons.math3.util.FastMath.copySign(double, double)

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.2
• Fix Version/s: 3.2
• Labels: patch performance

Environment

java version "1.6.0_27"
OpenJDK Runtime Environment (IcedTea6 1.12.3) (6b27-1.12.3-1)
OpenJDK 64-Bit Server VM (build 20.0-b12, mixed mode)

Linux debian 3.2.0-4-amd64 #2 SMP Wed Jan 2 01:41:29 PST 2013 x86_64 GNU/Linux

Intel(R) Core(TM) i5-2500 CPU @ 3.30GHz

• Assignee: Unassigned
• Reporter: Charles Cooper
• Created: 20/Mar/13 01:25
• Updated: 07/Apr/13 09:21
• Resolved: 22/Mar/13 16:26

Description

Between 40-50% faster than both current implementation and java.lang.Math.copySign by my (sloppy) benchmark. Patch attached.