> From Roger Hui
> Sat Feb 27 02:58:52 HKT 2010
> a. It matters a great deal what kind of keys you have.
> b. It matters what the pattern of put and get is like.
Keys are arbitrary strings, sizes ranging 10-100. Maybe occasional 1000.
Number of Gets is about same as number of puts (within factor of 10).
I am not looking for best solution, just for good enough. Exactly like
perl hashes. I do not know how they are implemented and quite possibly
in certain situations there are better strategies, but they do what
asked most of the time.
> c. The special code in J is for K&i. . But K has to
> be fixed.
I briefly considered redefining (tacit) get after each put to take
advantage of this fact. How much overhead we are talking about here?
What would be the ratio of gets to puts where it would make sense?
Assuming that K gradually grows into 1e5
> d. One method is to make K more than twice as
> big as the number of real keys, and rehash when
> the density exceeds 0.5.
I am not sure I understand that. Do you mean like preallocating space
and then reallocating it in chunks as need goes?
BTW, since some kind of code implementing dictionaries is already in the
interpreter, maybe you would consider exposing it through pair of 128!:x
foreigns? The only difference from assignment/evaluation would be that
it needs to accept arbitrary strings as 'names'.
_________________________________________________________________
Hotmail: Trusted email with powerful SPAM protection.
http://clk.atdmt.com/GBL/go/201469227/direct/01/
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
