Dear all, *-1: I don't really care what RealField.__repr__ returns, but cast a token no vote to object to the logical next move of breaking backwards compatibility by changing the meaning of RealField and/or RR. I see the need for a "genuine real field", but it seems a lot simpler just to call it something other than "RealField" and so not break a lot of existing users' Sage code. *
Perhaps I am just too naive as a newbie here, but I think the details of backwards compatibility can be discussed when it comes to the actual implementation of the "genuine" real field. We are barely there, and I think there are many compromises and gray zones possible than just "destroy the current behavior", right? By the way, has anyone considered my proposal? *I'd suggest a workaround: so what about "Real Field realized by Floating-point arithmetics of precision xx" and keep the above behavior? And then similarly for interval arithmetics and ball arithmetics* Whether we call it "realized", "represented" or "approximately represented", I think this is a good compromise, keeps the description rigorous and makes the step to a "genuine" real field much more comprehensible. I don't mind if you don't agree, but I'm curious about your opinions. Best, Michael dim...@gmail.com schrieb am Dienstag, 20. Oktober 2020 um 16:28:19 UTC+2: > > > On Tue, 20 Oct 2020, 15:12 Nathan Dunfield, <nat...@dunfield.info> wrote: > >> Well, seriously speaking, such drastic changes are needed sometimes, >>> and they demand a bump in the major version number, e.g. they can >>> happen in Sage 10.0. >>> >> It takes a lot of effort for a newcomer to get that RR and CC are >>> basically RDF and CDF on steroids, to get the mysteries of AA, etc >>> etc. >>> >> >> My perspective is partly coming as someone who has several papers that >> rely heavily on Sage computations. I've archived the code and data in a >> permanent fashion, but every backwards incompatible change Sage makes >> decreases the odds that anyone will be able to easily verify or extend my >> work five years from now. >> > > one needs to maintain the code, one can't just hope it will all magically > keep working in newer versions (it won't be true even if it was in plain > Python). > > And in this case a fix is trivial. > (and you have a chance to check along the way that it is still working) > > Certainly, changing the versions of RealField will break all of it. As >> you say, such changes are sometimes necessary. However, if Sage can solve >> the same technical problem by calling the new real number overclass >> GenuineRealField (or whatever) rather than stealing the name of the current >> RealField, I am arguing that it is not. >> > >> With regards to newcomers, I don't think having "RealField" be some >> abstract base class which is rarely what they need is going to help them, >> and any scheme for working with reals on a computer is going to be a bit >> complicated. I will also point out that intermediate users hate-hate-hate >> having their old notebooks and code no longer work. To any of us, fixing >> something like this is a simple search and replace after glancing at the >> traceback to realize what the issue is, but things like this are incredibly >> frustrating to more occasional users who view tracebacks as >> incomprehensible. >> >> Best, >> >> Nathan >> > -- >> > 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+...@googlegroups.com. >> > To view this discussion on the web visit >> https://groups.google.com/d/msgid/sage-devel/128f0019-1979-4c17-a902-33528232f060n%40googlegroups.com >> >> <https://groups.google.com/d/msgid/sage-devel/128f0019-1979-4c17-a902-33528232f060n%40googlegroups.com?utm_medium=email&utm_source=footer> >> . >> > -- 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 view this discussion on the web visit https://groups.google.com/d/msgid/sage-devel/ac1ab546-428c-4500-8f86-a558d4a03224n%40googlegroups.com.
