R help - Mar 2009 - Simple Plot with Grid's Viewport

Dear all,

I have the following code that try to plot
simple sinus curve into 2x2 grid in 1 page.

But this code of mine create 4 plots in 1 page
each. What's wrong with my approach?

__BEGIN__
library(lattice)
library(grid)

test.plot <- function(x,y) {
  pushViewport(viewport(layout.pos.col=x, layout.pos.row=y))
  pushViewport(viewport(width=0.6, height=0.6));
  plot(sin,-pi,2*pi, main= paste(c(i,j),collapse="-") )

}

plotfn <- ("~/Desktop/mygrid.pdf")
pdf(plotfn)
id = 0;
for (i in 1:2) {
    for (j in 1:2) {

        id = id+1;
        cat(i, "-", j, "\n", sep="")
        test.plot(i,j);
    }
}

dev.off()

__END__

- Gundala Viswanath

Gundala Viswanath <gundalav <at> gmail.com> writes:
> I have the following code that try to plot
> simple sinus curve into 2x2 grid in 1 page.
> 
> But this code of mine create 4 plots in 1 page
> each. What's wrong with my approach?
...
> library(lattice)
> library(grid)
> 
> test.plot <- function(x,y) {
>   pushViewport(viewport(layout.pos.col=x, layout.pos.row=y))
>   pushViewport(viewport(width=0.6, height=0.6));
>   plot(sin,-pi,2*pi, main= paste(c(i,j),collapse="-") )
> 
> }
> 
...         test.plot(i,j);

plot (plot.default) is "old-style" graphics and dates before grid. 
Note that your program would run without error when you remove 
the library(grid).

Use print(xyplot(..)) instead, or use par(...) to generate the
layout for your standard plots.

Dieter