Review Request: BigInteger patch for efficient multiplication and division (#4837946)

Brian Burkhalter brian.burkhalter at oracle.com
Mon May 13 18:57:31 UTC 2013


On May 11, 2013, at 8:35 PM, Alan Eliasen wrote:

> On 05/09/2013 03:02 PM, Brian Burkhalter wrote:
>>> First you have:
>>> 
>>>   /**
>>>    * The threshold value for using 3-way Toom-Cook multiplication.
>>>    * If the number of ints in both mag arrays are greater than this number,
>>>    * then Toom-Cook multiplication will be used.   This value is found
>>>    * experimentally to work well.
>>>    */
>>>   private static final int TOOM_COOK_THRESHOLD = 75;
> 
>   You're right that the actual code will use Toom-Cook if 1.) both of
> the numbers are greater than the Karatsuba threshold *and* 2.) at least
> one of the numbers is greater than the Toom-Cook threshold.
> […]
>   If you want to change the comment to something like my first sentence
> in the first paragraph, that would be fine.  Alternately, we could
> change the logic to match the comment, but that would probably mean that
> we should re-tune the thresholds.

I would prefer simply to change the javadoc of the constant unless others have a strong preference otherwise.

Brian


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