[R] An opinion question, please

[Eric Berger]

If you are writing a new package I don't see why you should restrict
yourself to S3 or S4 classes.
Your "new package" can certainly build on other packages. (Why not?)
As I wrote in my previous email, if you are dealing with time series
you might want to consider appropriate classes already defined in
other packages, such as those obtained via

library(fpp3)

In my work, I deal with many financial time series. I highly recommend
the xts package which is a subclass of the zoo class. The zoo class is
an S3 time series class built on matrix.
The xts class is "designed for fast, consistent time-based indexing,
ideal for financial time series" (quoting ChatGPT here).

The xts package is maintained by Joshua Ulrich who is extremely active
and helpful in responding to questions about xts in the R-help lists.

HTH,
Eric

On Tue, Apr 8, 2025 at 2:24 AM Erin Hodgess <erinm.hodgess using gmail.com> wrote:
>
> We can have different frequencies of data, including Business day data and
> daily data as our outputs.
>
> Both of those will start on Monday.
>
> Erin Hodgess, PhD
> mailto: erinm.hodgess using gmail.com
>
>
> On Mon, Apr 7, 2025 at 4:57 PM CALUM POLWART <polc1410 using gmail.com> wrote:
>
> > Clearly something has gone terribly wrong. Everyone is saying use S3. This
> > is an online discussion... So someone needs to support S4.
> >
> > Which frighteningly seems to be me! I'd caution you now... I first used an
> > S4 object about two weeks ago and still have no real idea if they do what I
> > think they do!
> >
> > My understanding is S4 objects can hold the source data and the commands
> > to make the result data. Which means in terms of reproduction of results
> > this may be better...
> >
> > ...I'm not at all sure I know what you want to do with your data. But
> > assuming you started with a time series of daily maximum temperature, I
> > think with an S4 object the daily maximum can be saved, plus the week,
> > month, season, year etc.
> >
> > If week could begin on a Monday or a Sunday, the info that is used to
> > decide is stored for reference.
> >
> > S4 can enforce data types.
> >
> > On Mon, 7 Apr 2025, 22:40 Jeff Newmiller via R-help, <r-help using r-project.org>
> > wrote:
> >
> >> My opinion is that you should use S3 unless you absolutely need some
> >> syntactic sugar only offered by some other object system.
> >>
> >> Note that in a majority of cases you want to transform one standard data
> >> structure to another... tibble to tibble is the fashion for dplyr... and
> >> functions can often do what you want just fine except that they sometimes
> >> end up needing a lot of arguments that you want to refer to in many places.
> >> You can often make a class that holds those arguments so they can be
> >> re-used and where the class has methods to do the desired transformation
> >> (s) where the bulk data remains handled as arguments and return values
> >> rather than as data in the object itself.
> >>
> >> The lm class in base R uses a "constructor computes and methods retrieve
> >> results" approach... which isn't quite as flexible as a transformer
> >> approach but still hides the gory details.
> >>
> >> My reason for giving these examples is that the functional/OO approach
> >> expresses problems quite cleanly using S3... and you don't have to pay the
> >> performance/hoop-jumping/extra dependencies that you need for R5 or R7.
> >> That is, you should think carefully about whether you really need whatever
> >> features that more advanced OO system offers... and then you will know the
> >> answer to the question you posed for yourself.
> >>
> >> On April 7, 2025 10:35:44 AM PDT, Erin Hodgess <erinm.hodgess using gmail.com>
> >> wrote:
> >> >Hello everyone!
> >> >
> >> >I have an opinion question please.  If I’m writing a new package, would
> >> you
> >> >recommend using S3 or S4 structure, please?
> >> >
> >> >I know I will get lots of opinions, but that’s fine.
> >> >
> >> >Thanks,
> >> >Erin
> >> >
> >> >
> >> >Erin Hodgess, PhD
> >> >mailto: erinm.hodgess using gmail.com
> >> >
> >> >       [[alternative HTML version deleted]]
> >> >
> >> >______________________________________________
> >> >R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >> >https://stat.ethz.ch/mailman/listinfo/r-help
> >> >PLEASE do read the posting guide
> >> https://www.R-project.org/posting-guide.html
> >> >and provide commented, minimal, self-contained, reproducible code.
> >>
> >> --
> >> Sent from my phone. Please excuse my brevity.
> >>
> >> ______________________________________________
> >> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> >> https://stat.ethz.ch/mailman/listinfo/r-help
> >> PLEASE do read the posting guide
> >> https://www.R-project.org/posting-guide.html
> >> and provide commented, minimal, self-contained, reproducible code.
> >>
> >
>
>         [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide https://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.