Dear Deepayan, I see your point. I must admit that I was considering only formula's as x argument for the trellis plots. What I would really like to have in your example, would be
barchart.matrix <- function (x, data = NULL, ...) { foo <- barchart(as.table(x), data, ...) foo$call <- match.call() foo$call[[1]] <- quote(barchart) foo } > summary(barchart(VADeaths)) Call: barchart(x = VADeaths) Number of observations: [1] 20 > summary(barchart(VADeaths))$call$x VADeaths That's nice both for cosmetic and programming. However that would require changes to all the methods for trellis functions and it is also possible that I'm missing something else, so I'll understand if you decide not to implement this. Thanks in advance anyway Vincenzo ----------------------------------------------------------------------------------- Vincenzo Luca Di Iorio Consultant PME User support - GSK R&D Limited ----------------------------------------------------------------------------------- "Deepayan Sarkar" <deepayan.sar...@gmail.com> 14-Aug-2009 21:15 To vincenzo.2.di-io...@gsk.com cc "R help" <r-h...@stat.math.ethz.ch> Subject Re: [R] Retrieving x argument name from a trellis object On Fri, Aug 14, 2009 at 11:04 AM, <vincenzo.2.di-io...@gsk.com> wrote: > > Dear Deepayan, > > First of all I'm sorry for resuming such an old thread, but I think I may > have found an easy fix. > > Replacing in "xyplot.formula" (and similar internal functions for the other > Trellis plots) > > foo$call <- sys.call(sys.parent()) > foo$call[[1]] <- quote(xyplot) > > with > > foo$call <- match.call() > foo$call[[1]] <- quote(xyplot) > > will restore the correct behaviour while keeping the new better value for > the call component of a trellis object introduced in lattice version 0.16 or > higher, that if I understand correctly depends on the second (unchanged) > line. But consider this: we currently get > vad <- as.table(VADeaths) > summary(barchart(vad)) Call: barchart(vad) Number of observations: [1] 20 > summary(barchart(VADeaths)) Call: barchart(as.table(x), data, ...) Number of observations: [1] 20 Not perfect, but not too bad either, considering that neither barchart.matrix() nor barchart.table() do any manipulation of the $call component. If I make your suggested change in barchart.formula, this is what I get: > summary(barchart(VADeaths)) Call: barchart(x = as.formula(form), data = data, groups = eval(groups), origin = origin, stack = stack) Number of observations: [1] 20 Which would you rather have? The point remains that the call component is meant for cosmetic use. If you can convince me that having the other form is important, I will be happy to include it in the "trellis" object (under a different name, perhaps "mcall"). -Deepayan > > Best regards > Vincenzo > > ----------------------------------------------------------------------------------- > Vincenzo Luca Di Iorio > Consultant PME User support - GSK R&D Limited > ----------------------------------------------------------------------------------- > > > > "Deepayan Sarkar" <deepayan.sar...@gmail.com> > > 12-Nov-2008 07:04 > > > To > "vincenzo.2.di-io...@gsk.com" <vincenzo.2.di-io...@gsk.com> > cc > "R help" <r-h...@stat.math.ethz.ch> > Subject > Re: [R] Retrieving x argument name from a trellis object in R 2.8.0 > > > > > On 11/11/08, vincenzo.2.di-io...@gsk.com <vincenzo.2.di-io...@gsk.com> > wrote: >> Dear all, >> >> let consider the following function: >> >> Fun1 <- function() { >> library(lattice) >> plot1 <- 1:10~1:10 >> pl1 <- xyplot(plot1) >> return(pl1$call$x) >> } >> >> In R 2.5.0 (or older version) we have >> >> > Fun1() >> plot1 >> >> but starting from R 2.5.1 until the latest R 2.8.0 we obtain instead >> >> > Fun1() >> NULL >> >> because pl1$call seems to be equal to xyplot() without arguments. >> >> Something like xyplot(x=plot1) doesn?t work either. Again we have that >> pl1$call is equal to xyplot() without arguments >> >> The situation is slightly different if we call the xyplot in the global >> environment: >> >> > plot1 <- 1:10~1:10 >> > pl1 <- xyplot(plot1) >> > pl2 <- xyplot(x=plot1) >> >> then we have >> >> > pl1$call >> xyplot(plot1) >> > pl1$call$x >> NULL >> >> but at least >> >> > pl2$call >> xyplot(x = plot1) >> > pl2$call$x >> plot1 > > This is what I would have expected. > > I'm surprised at the odd behaviour when xyplot() is called inside a > function, which is probably caused by my lack of understanding of how > sys.call() works. However, the 'call' component is provided mainly for > cosmetic reasons, and was never intended to be used programmatically. > Why do you need this? > > -Deepayan > >> Someone knows if in R 2.8.0 it is possible to retrieve the name of the x >> argument (i.e. plot1) directly from an object of class ?trellis? when the >> corresponding lattice function (e.g. xyplot) is inside another function >> (e.g. Fun1)? >> >> Thanks in advance >> Vincenzo >> >> >> ----------------------------------------------------------------------------------- >> Vincenzo Luca Di Iorio >> Consultant PME User support - GSK R&D Limited >> >> ----------------------------------------------------------------------------------- >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help@r-project.org mailing list >> 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. >> > > > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list 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.