Problems using lattice in a function?

Hello list,

I've created a function incorporating lattice, and I'm getting weird results that I can't explain?

Here's the results I would like to have, without encapsulating it into a function (this works without problems):

A <- data.frame(x = rnorm(100), y = rnorm(100)) 
  xyplot(y ~ x, data = A) 
  trellis.focus("toplevel") ## has coordinate system [0,1] x [0,1] 
  panel.text(c(0.5, 0.6, 0.7), c(0.4, 0.2, 0.3), c("A", "B", "C"), cex = 1.2, font = 2) 
  trellis.unfocus()


I thought I could make up a function as such to do the same thing:

test <- function(xi, yi, li){
	A <- data.frame(x = rnorm(100), y = rnorm(100)) 
	  p <- xyplot(y ~ x, data = A)
	  trellis.focus("toplevel") ## has coordinate system [0,1] x [0,1] 
	  p <- p + layer(panel.text(xi, yi, li, cex = 1.2, font = 2))
	  trellis.unfocus()
	  
	  return(p)
}

test(c(0.5, 0.6, 0.7), c(0.4, 0.2, 0.3), c("A", "B", "C"))


With my function, I get an error for the panel.text part, with the message "Error using packet 1    object 'xi' not found".

Any help on this would be greatly appreciated!


Best regards,

Jooil


----------------------------------------------------
Jooil Kim
Postdoc Fellow
Scripps Institution of Oceanography, UC San Diego
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