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Alexis Robert commented on MATH-650: ------------------------------------ commons-math svn r1169543 / FastMath.USE_PRECOMPUTED_TABLES = false : 0.122ms commons-math svn r1169543 / FastMath.USE_PRECOMPUTED_TABLES = true : 0.152ms I've done the tests twice, and I still get higher execution time for USE_PRECOMPUTED_TABLES = true. > FastMath has static code which slows the first access to FastMath > ----------------------------------------------------------------- > > Key: MATH-650 > URL: https://issues.apache.org/jira/browse/MATH-650 > Project: Commons Math > Issue Type: Improvement > Affects Versions: Nightly Builds > Environment: Android 2.3 (Dalvik VM with JIT) > Reporter: Alexis Robert > Priority: Minor > Attachments: FastMathLoadCheck.java > > > Working on an Android application using Orekit, I've discovered that a simple > FastMath.floor() takes about 4 to 5 secs on a 1GHz Nexus One phone (only the > first time it's called). I've launched the Android profiling tool (traceview) > and the problem seems to be linked with the static portion of FastMath code > named "// Initialize tables" > The timing resulted in : > - FastMath.slowexp (40.8%) > - FastMath.expint (39.2%) > \- FastMath.quadmult() (95.6% of expint) > - FastMath.slowlog (18.2%) > Hoping that would help > Thanks! > Alexis Robert -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira