[R] cloud plot has white(transparent?) background

[David Winsemius]

Karin Lagesen <karin.lagesen at medisin.uio.no> wrote in
news:ypx6prsixgly.fsf at alanine.uio.no: 

> I am using the code example from the R graph gallery to look at a
> cloud plot:
> 
> require(lattice) 
> data(iris) 
> print(cloud(Sepal.Length ~ Petal.Length * Petal.Width, data = iris, 
>             groups = Species, screen = list(z = 20, x = -70), 
>             perspective = FALSE,
>             key = list(title = "Iris Data", x = .15, y=.85, corner =
>             c(0,1), border = TRUE,
>             points = Rows(trellis.par.get("superpose.symbol"), 1:3),
>             text = list(levels(iris$Species))))) 
> 
> Now, in the example on the webpage this comes out with a nice gray
> background that makes things easier to see. Mine comes out with a
> white, potentially transparent background and also the point colors
> have changed.
> 
> How do I get the nice gray color back?

I think the grey obscures the plot, but with some searching of the help 
files, displaying the rather extensive list from 
trellis.par.get(name = NULL)  ... and then finding "Graphical 
Parameters for Trellis Displays", this seems to do what's desired, ...

 background <- trellis.par.get("background")
 background$col <- "grey"
 trellis.par.set("background", background)

> print(cloud(Sepal.Length ~ Petal.Length * Petal.Width, data = iris,
+             groups = Species, screen = list(z = 20, x = -70),
+             perspective = FALSE,
+             key = list(title = "Iris Data", x = .15, y=.85, corner = 
c(0,1),
+             border = TRUE,
+             points = Rows(trellis.par.get("superpose.symbol"), 1:3),
+             text = list(levels(iris$Species))
+              )))

(I initially tried ...
 trellis.par.set(background$col, "grey") #fails)


-- 
David Winsemius