[R] Does anyone have any use for this?

[Abby Spurdle]

And it was supposed to say billions.

plt (main="Monthly NZ GDP (Billions)")


On Sat, Jan 2, 2021 at 2:32 PM Abby Spurdle <spurdle.a using gmail.com> wrote:
>
> I'm not enthusiastic about nonstandard evaluation and allowing
> functions to change state data.
> Currently, I use some of this in my own packages, but I'm planning to
> remove most of it.
>
> But I did have some fun with your function.
>
> ----------
> plt <- memify (plot)
>
> x <- 1:12
> y1 <- seq (0, 18,, 12)
> y2 <- c (
>     16.88, 16.04, 13.23, 13.88, 11.85, 9.61,
>      9.28,  5.81,  7.52,  3.40,  3.37, 0.07)
>
> #test 1
> plt (x, y1, type="l")
> #test 2
> plt (ylim = c (18, 0) )
>
> #important econometric timeseries analysis
> plt (y=y2, main="Monthly NZ GDP (Millions)")
> ----------
>
> Note:
> This data is not accurate.
>
>
> On Sat, Jan 2, 2021 at 9:20 AM Bert Gunter <bgunter.4567 using gmail.com> wrote:
> >
> > Hi all:
> >
> > In the course of playing around with other issues, I wrote the following
> > little function that allows functions to keep state
> > and easily replay and update their state.(see comments after):
> >
> > memify <- function(f)
> > {
> >    if (is.primitive(f)) {
> >       cat("Cannot memify primitive functions.\n")
> >       return(NULL)
> >    }
> >    if (!inherits(f, "function"))
> >       stop("Argument must inherit from class 'function'")
> >    arglist <- list()
> >    structure(
> >       function(...) {
> >          m <- tryCatch(
> >             as.list(match.call(f)[-1]),
> >             error = function(e) {
> >                warning("Bad function call; cannot update arguments\n")
> >                return(NULL)
> >             }
> >          )
> >          nm <- names(m)
> >          hasname <- nm != "" #logical index of named values
> >          if (any(hasname)) {
> >             if (anyDuplicated(nm, incomparables = ""))
> >                warning("Duplicated names in call; only the first will be
> > used.")
> >             arglist <<- modifyList(arglist, m[hasname]) ## this is what
> > does the job
> >          }
> >          do.call(f, modifyList(m, arglist))
> >       },
> >       class = c("memified", class(f)))
> > }
> >
> > Examples:
> >
> >  x <- 1:9; y <- runif(9)
> >  plt <- memify(plot)
> >  x <- 1:9; y <- runif(9)
> >  plt(x,y, col = "blue")  ## plt "remembers" these arguments; i.e. keeps
> > state
> >  plt( type = "b") ## all other arguments as previous
> >  plt(col = "red") ## ditto
> >
> > So my question is: Beyond allowing one to easily change/add argument values
> > and replay when there are lots of arguments floating around, which we often
> > use an IDE's editor to do, is there any real use for this? I confess that,
> > like Pygmalion, I have been charmed by this idea, but it could well be
> > useless, By all means feel free to chastise me if so.
> >
> > 1. I am aware that many functions already have "update" methods to "update"
> > their results without re-entering all arguments -- e.g. lattice graphics,
> > glm, etc.
> > 2. Several packages -- rlang and R6 anyway -- but very likely more, do this
> > sort of thing and way more; the price is added complexity, of course.
> > 3. I realize also that keeping state would be a bad idea in many
> > circumstances, e.g. essentially changing documented defaults.
> >
> > Reply privately to praise or bury if you do not think this is of any
> > interest to readers of this list. Publicly is fine, too. If it's dumb it's
> > dumb.
> >
> > Cheers and best wishes for a better new year for us all,
> >
> > Bert Gunter
> >
> >         [[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 http://www.R-project.org/posting-guide.html
> > and provide commented, minimal, self-contained, reproducible code.