On 8/6/12 2:28 PM, Gilles Sadowski wrote: > On Mon, Aug 06, 2012 at 12:44:24PM -0700, Phil Steitz wrote: >> On 8/6/12 11:41 AM, Gilles Sadowski wrote: >>>>> [...] >>>>>>> The RandomData class (or whatever it would be called) does indeed seem >>>>>>> useful. If we plan to keep it, we should probably make sure that there >>>>>>> is a sample/next/... method in that class for EVERY distribution, as >>>>>>> some of them are missing, if I remember correctly. Perhaps this is a >>>>>>> separate issue though? >>>>>>> >>>>>> All have the method now, but the impls delegate to RandomDataImpl. >>>>> They do not. >>>> The method is in the interface. There is a default, inversion-based >>>> implementation in the abstract base class. Not all distributions override >>>> the default impl. >>>> The ones that do delegate to the specialized methods in RandomDataImpl >>> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ >>> >>> No; as indicated before (cf. message referred to below), the distribution >>> classes do not delegate anymore to "RandomDataImpl", since revision 1363604 >>> (resolution of MATH-764 and MATH-823). >> Sorry, my mistake. I see the code has been duplicated. I will see >> if I can modify the methods in RandomDataImpl to use the impls in >> the distribution classes. Should be possible by creating instances >> using the configured RandomGenerator. > Yes, that was what I also proposed when we started talking about > transferring the (sampling) code from RAndomDataImpl over to the "sample()" > methods. > >> See more below. >>>>>> In some cases, there is nothing better implemented than just inversion, >>>>>> provided by the default inversion sampler. That is OK. What we need to >>>>>> do is just move the implementations of the default and specialized >>>>>> samplers to the actual distribution classes. These can't be static, as >>>>>> they use the RamdomData instance. I will take care of this. >>>>> Thanks for reading fully this message >>>>> http://markmail.org/message/5fpmwyiiw2xq4o3q >>>> I don't get the desire to make sample() static. >>> There is no such desire stated in that message. >>> The proposed static method is a "helper" that will take everything needed as >>> arguments. It will be defined in the appropriate distribution class, to be >>> called both by "sample()" from that class and by the convenience methods in >>> "RandomDataImpl". >> OK, I now think I get what you mean. Non-static methods of >> "RandomDataImpl" could use static methods from the distribution >> classes, passing the configured RandomGenerator as an argument. Is >> that what you mean? > Yes! :-) > >> I don't know how much direct usage the static >> methods in the distribution classes would get; since most actual >> examples involve generating sequences using the same generator >> repeatedly (so sample() is more natural). > I totally agree. They would exist only for the sake of not duplicating the > sampling code. > >> I guess "RandomDataImpl" >> would then not have to instantiate distributions, but there is not >> much overhead to creating the ones we have, so not sure it is worth >> the effort to add all of these methods. > Fine then. I'd also prefer not to create new public methods just for the > sake of a convenience class. > I.e. we could mention (in "RandomDataImpl") that the convenience comes at a > slight efficiency cost. [And that for heavy usage of sampling, one should > use the distribution classes directly.]
OK, sorry to be a little thick on this. I think I can do this. Thanks! Phil > > > Gilles > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
