Investigate on optimizations on statistical processing

[GoogleCodeExporter]

Using yourkit profiler, I have found "some computation time" spent when 
offering samples to the statistical processor. (Since I was iterating over 
million of samples) (see the attached screenshot).

Looking into the calls, a certain amount of time is spent when invoking the 
generic NumberOperations.calculate method when checking for the range 
containment (since it needs to instantiate a new number, get a higherclass, get 
the class type from the map, ...).

Since most part of the computations on range deal with doubles (The ranges 
provided to abstractProcessor are explicitly Range<Double>), could we define 
some "specific" management which directly deals with doubles by avoiding any 
conversion, cast, check for class, new instance creation, ...?

I did some workaround on our 1.2-classified branch to deal with doubles.
Although that isn't the best approach/solution it depicts big performance 
improvements we may justify some investigations on the topic. 

On some sample data I was processing, the stats computations ended after 17 - 
18 seconds with the old code. Using the new one, the same tests ends in 10 
seconds.

Original issue reported on code.google.com by dany.Geo...@gmail.com on 10 Aug 2011 at 9:24

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[GoogleCodeExporter]

I think r1870 has included your optimizations Daniele. Please re-open this 
issue if there is more to do.

Original comment by michael.bedward@gmail.com on 20 Sep 2012 at 2:25

• Changed state: Fixed