[java] Fast Matrix

It''s going to depend on the JVm and JIT in use at the time it''s run.

I would say take you #1 platform and test both and see. If you have no #1 platform or want to keep it agnostic as possible use [][] as it''s cleaner code and more likly to be optimized by newer ( and newer ) JIT engines.

Good luck.

Actually faster might include a version that uses int''s or longs as floating point is notorious for slowdowns under java.

Look up some old code on fixed floating point matrix operations.

Hi!

The second alternative should always be the fastest.

Why?

The reason is simple. If you take a look at the Java Virtual Machine Specifiation you get a better understanding of the problem.

My short version is;
All Java arrays are stored as Java objects. In the 1st case you have to do two searches in the object heap. In the 2nd case you only have to make one search.

I don´t see how two searches could be faster than one searh.

BTW. I have done performance test of no less than 8 different JVM´s on Solaris. All did have the same behaviour.

Regards
Johan



Johan Karlsson

Heya,

Cool, 3D Engines in Java!
Check example of mine at www.student.tue.nl/u/e.bastianen

Gr,
BoRReL

Thanks!!

Gr,
BoRReL