Hi Andrew, On 2018-09-27 15:28, Andrew Haley wrote: > On 09/27/2018 01:23 PM, Raffaello Giulietti wrote: > >> In principle I agree with you. >> >> However, in this case the maths underlying the algorithm to select the >> decimal are too involved to explain in comment form. I'm in the course >> of preparing a paper that explains the idea and the details. Then it >> should be easier to make sense out of the code. > > In which case, the code must contain pointers to the relevant parts of > the paper. >
Sure. >> Since to my knowledge the algorithm is novel, it will require some time >> for me to translate in paper form. > > Sure, but how do you expect anyone to review your code without the > necessary explanation? Do you think that people should approve your > patch without that paper? > I've no idea on how OpenJDK code is reviewed, so I cannot honestly answer your questions. What I can tell is that if I were a reviewer, I wouldn't trust rather involved code like mine without an explanation, exactly as you seem inclined to do. On the other side, in April this year I submitted another quite fast and supposedly correct algorithm on this mailing list and I referred to an accompanying paper by myself that gives full explanations on that variant. Except for a couple of persons in private, nobody cared to send me any observation or comment, neither on the code nor on the paper. The present algorithm is superior. I have the theory in notes, in my head, on napkins, on paper sheets all over my desk and floors. But rather than spending time on the paper itself, like I did almost in vain for the April variant, I preferred investing it in coding, for several reasons: * Only code executes, not a paper. * Only code gives results that can be compared against. * Only code can give indications on performance enhancements. * Only code is interesting to be submitted to the OpenJDK. * Having a paper without having tried the ideas in code is half the fun and half as useful. It's only a matter of priorities and of limited time, my spare time. That said, now that I have some feedback and that the code has been exercised at least some 400 billions times on doubles without errors and on all 2^32 floats without errors, I now know that there is some interest and that it is worth pushing energies in the paper. >> There are some succinct comments here that explain the expected >> results. I'm not the kind of programmer that comments every line >> since here the mechanics is simple enough to follow in Java >> directly. A good explanation would either be mathematical, which >> requires better typography than US-ASCII, or some explanatory >> drawings. > > Sure, these can be offline somewhere. The difficulty is always the > mapping from the mathematics onto the Java code, and this is what must > be explained in the comments. > ... or in the paper. Greetings Raffaello