On 26 August 2014 14:49, Vincent Delecroix <20100.delecr...@gmail.com> wrote: > 2014-08-26 15:22 UTC+02:00, William A Stein <wst...@uw.edu>: >> On Tue, Aug 26, 2014 at 3:12 PM, John Cremona <john.crem...@gmail.com> >> wrote: >>> Sounds like a reasonable plan if you (or someone) can be bothered to >>> sort out the chenges which will need to be made in code and doctests! >> >> Even then, personally I don't like it. See below for a different >> suggestion that is less intrusive. >> >>> There will be places where we now have: for p in primes(10^8): >>> do_something_with(p) which will still work when primes() returns a >>> list, so will not result in doctest failures, but which should be >>> changed. This will be rather tedious. >>> >>> On the plus side, I make the point that all these are functions at the >>> top level which will be discovered by beginners for whom >>> >>> sage: primes(100) >>> <generator object primes at 0x7f9335465a50> >>> >>> will just confuse. Experts can know about and use the iterator forms >>> of the functions. >> >> We could certainly make it do this with little effort: >> >> sage: P = primes(100); P >> Prime numbers of less than 100 >> >> We could then have >> >> for x in P: >> ... >> >> be the usual iterator. One could also do: >> >> sage: P.list() >> [...] >> >> to get back a list. And one could do >> >> sage: len(P) >> >> to get the number of primes, without computing them. So... my >> counterproposal is to make primes return a cython class with a few >> methods. This breaks new code, and will be more new user friendly. > > We already have Primes (upper case P) for that... it just need to be > tuned to accept lower/upper bounds. It is nicer from the user point of > view (as far as OOP is better than functional programming). A good > solution for the namespace would be to have only Primes and > PrimePowers. > > But I really will not use it myself because it has a classcall, > UniqueRepresentation, category, etc which takes lifetime to > initialize. My loops are rather small but I have plenty of them... so > having a nice Primes object would only be painful. I want to keep a > simple Cython function that returns list or iterator. >
We could have both, surely? William's nice python class would be what users find, in the main namespace, while the lower level functions could still be there (with no additional overheads) to be imported by those who need them, including use in library code. John > Vincent > > -- > You received this message because you are subscribed to the Google Groups > "sage-nt" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sage-nt+unsubscr...@googlegroups.com. > To post to this group, send an email to sage...@googlegroups.com. > Visit this group at http://groups.google.com/group/sage-nt. > For more options, visit https://groups.google.com/d/optout. -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
