[Rd] Allowing S3 methods of rounding functions to take `...`
Abby Spurdle (/əˈbi/)
@purd|e@@ @end|ng |rom gm@||@com
Mon Feb 1 07:31:27 CET 2021
I've used S4 objects but with mostly S3 methods.
Currently, with two different versions.
(One extending a general purpose ObjectArray object, and the other
with partitioning information).
Sample below.
However, I'd really like to get back the suggestion(s) of adding
"dots" to the S3 methods.
I know I've said similar things before, but I think minimizing
constraints on object oriented programming is a good thing...
That principle applies to both S3 and S4...
#mono-fonts req. to read this
> x <- matrix (1:256, 8, 8)
> pm <- as.PartMatrix (x, c (2, 6), c (2, 6) )
> as.NestMatrix (pm)
[,1] [,2] [,3]
[1,] <m 2x2> <m 2x4> <m 2x2>
[2,] <m 4x2> <m 4x4> <m 4x2>
[3,] <m 2x2> <m 2x4> <m 2x2>
> headt (pm, 4, c (1, 4) )
[,1] [,2] [,3] [,6] [,7] [,8]
[1,] 1 9 | 17 . 41 | 49 57
[2,] 2 10 | 18 . 42 | 50 58
-- -- + -- . -- + -- --
[3,] 3 11 | 19 . 43 | 51 59
.. .. .. .. . .. .. .. ..
[8,] 8 16 | 24 . 48 | 56 64
On Sat, Jan 30, 2021 at 7:51 AM David Winsemius <dwinsemius using comcast.net> wrote:
>
>
> On 1/28/21 10:56 PM, Abby Spurdle wrote:
> > I've been writing functions for block matrices and more generally,
> > arrays of matrices.
> >
> > Presumably, the default transpose operation would transpose everything.
> > But there are situations where one might want to transpose the
> > top-level matrix (of submatrices) but not the submatrices, themselves.
> > Or vice versa.
>
>
> You could construct a matrix of lists and have the lists hold the
> sub-matrices.
>
>
> --
>
> David.
>
> >
> > On a side note, the help file for base::aperm is entitled "Array Transposition".
> > So, this topic is not quite as simple as it may sound.
> >
> > Interestingly, the aperm generic function *does* have dots.
> >
> >
> > On Fri, Jan 29, 2021 at 3:37 PM Gabriel Becker <gabembecker using gmail.com> wrote:
> >> Out of my naive curiosity, what arguments are you hoping a method for t() will take?
> >>
> >> I mean honestly an argument could be made that all S3 generics should take .... I don't think its an overwhelmingly compelling one, but I d see some merit to it given what an s3 generic is at its core.
> >>
> >> ~G
> >>
> >> On Thu, Jan 28, 2021 at 5:27 PM Abby Spurdle <spurdle.a using gmail.com> wrote:
> >>> That's a great suggestion Davis.
> >>>
> >>> While, we're on the topic...
> >>> Could we have a "dots" argument in base::t, the transpose function?
> >>>
> >>>
> >>> On Fri, Jan 29, 2021 at 4:48 AM Davis Vaughan <davis using rstudio.com> wrote:
> >>>> I should also say that I would be willing to attempt a patch for this, if
> >>>> others agree that this would be useful.
> >>>>
> >>>> - Davis
> >>>>
> >>>> On Thu, Jan 28, 2021 at 9:14 AM Davis Vaughan <davis using rstudio.com> wrote:
> >>>>
> >>>>> Hi all,
> >>>>>
> >>>>> I would like to propose adding `...` to the signatures of the following
> >>>>> rounding functions:
> >>>>>
> >>>>> - floor(x)
> >>>>> - ceiling(x)
> >>>>> - round(x, digits = 0)
> >>>>> - And possibly signif(x, digits = 6)
> >>>>>
> >>>>> The purpose would be to allow S3 methods to add additional arguments as
> >>>>> required.
> >>>>>
> >>>>> A few arguments in favor of this change:
> >>>>>
> >>>>> `trunc(x, ...)` already takes dots, which sets a precedent for the others
> >>>>> to do so as well. It is documented in the same help file as the other
> >>>>> rounding functions.
> >>>>>
> >>>>> Internally at the C level, a check is done to ensure that there is exactly
> >>>>> 1 arg for floor() and ceiling(), and either 1 or 2 args for round(). The
> >>>>> actual names of those arguments are not checked, however, and I believe
> >>>>> this is what allows `round.Date(x, ...)` and `round.POSIXt(x, unit)` to
> >>>>> exist, solely because they have 2 arguments. It seems like this is a bit of
> >>>>> a hack, since you couldn't create something similar for floor, like
> >>>>> `floor.POSIXt(x, unit)` (not saying this should exist, it is just for
> >>>>> argument's sake), because the 1 argument check would error on this. I think
> >>>>> adding `...` to the signature of the generics would better support what is
> >>>>> being done here.
> >>>>>
> >>>>> Additionally, I have a custom date-like S3 class of my own that I would
> >>>>> like to write floor(), ceiling(), and round() methods for, and they would
> >>>>> require passing additional arguments.
> >>>>>
> >>>>> If R core would like to make this change, they could probably tweak
> >>>>> `do_trunc()` to be a bit more general, and use it for floor() and
> >>>>> ceiling(), since it already allows `...`.
> >>>>>
> >>>>> A few references:
> >>>>>
> >>>>> Check for 1 arg in do_math1(), used by floor() and ceiling()
> >>>>>
> >>>>> https://github.com/wch/r-source/blob/fe82da3baf849fcd3cc7dbc31c6abc72b57aa083/src/main/arithmetic.c#L1270
> >>>>>
> >>>>> Check for 2 args in do_Math2(), used by round()
> >>>>>
> >>>>> https://github.com/wch/r-source/blob/fe82da3baf849fcd3cc7dbc31c6abc72b57aa083/src/main/arithmetic.c#L1655
> >>>>>
> >>>>> do_trunc() definition that allows `...`
> >>>>>
> >>>>> https://github.com/wch/r-source/blob/fe82da3baf849fcd3cc7dbc31c6abc72b57aa083/src/main/arithmetic.c#L1329-L1340
> >>>>>
> >>>>> - Davis
> >>>>>
> >>>> [[alternative HTML version deleted]]
> >>>>
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