Nathaniel Smith writes: > On Fri, Jul 1, 2011 at 7:09 AM, Mark Wiebe <mwwi...@gmail.com> wrote: >> On Fri, Jul 1, 2011 at 6:58 AM, Matthew Brett <matthew.br...@gmail.com> >> wrote: >>> Do you see problems with the alterNEP proposal? >> >> Yes, I really like my design as it stands now, and the alterNEP removes a >> lot of the abstraction and interoperability that are in my opinion the best >> parts. I've made more updates to the NEP based on continuing feedback, which >> are part of the pull request I want reviews for. >> >>> >>> If so, what are they? >> >> Mainly: Reduced interoperability, more complex implementation (leading to >> more bugs), and an unclear theoretical model for the masked part of it.
> Can you give any examples of situations where one would run into this > "reduced interoperability"? I'm not sure what it means. The only > person who has so far spoken up as needing both masking semantics and > NA semantics -- Gary Strangman -- has said that he strongly prefers > the alterNEP semantics *exactly because* it makes it clear *how these > functions will interoperate.* Interoperability improves code maintenance, see my other mail. [...] > Do you have a clearer theoretical model for the masked part of your > proposal? The best I've been able to extract from any of your messages > is when you wrote "it seems to me that people wanting masked arrays > want missing data without touching their data". But as a matter of > English grammar, I have no idea what this means -- if you have data, > it's not missing! It seems to me that people wanting masked data want > to *hide* parts of their data, which seems much clearer to me and is > the theoretical model used in the alterNEP. Note that this model > actually predicts several of the differences between how people want > masks to work and how people want NAs to work (e.g., their behavior > during reduction); I Come on, let's not jump into each other's throats, I think we've long ago arrived at a point where we all know what masked means. If you agree on the interoperability point, then I don't see how the aNEP improves on that, having in mind that masks must be *explicitly* activated (again, see the other mail). [...] > Well, that's not true. There are some marginal advantages in the > special case of working with integers+NAs. But I don't think anyone's > making that argument. I for one would love that, instead of having to explicitly set dtypes when using genfromtxt. [...] > But as far as I can tell right now, every single person who has > experience with handling missing data for statistical purposes (esp. > in R) has real concerns about your proposal, and AFAICT the community > has very much *not* reached consensus on how these features should > look. What I have seen is that people used to R see the mask concept as an alien, and said "I don't want to use it, so please make it more explicit so that I will know what to avoid". What I say is that you simply don't have to make np.IGNORE explicit to avoid masks. Simply do not create arrays with masks. Lluis -- "And it's much the same thing with knowledge, for whenever you learn something new, the whole world becomes that much richer." -- The Princess of Pure Reason, as told by Norton Juster in The Phantom Tollbooth _______________________________________________ NumPy-Discussion mailing list NumPy-Discussion@scipy.org http://mail.scipy.org/mailman/listinfo/numpy-discussion
