Bioequivalence and Bioavailability Forum

Hi ElMaestro,

❝ hot greetings from Ahmedabad.

Hope you enjoy it.

The problem with your code is that rect() does not – and can not – ‘know’ how wide text() will be.

A workaround:

foo2 <- function(name, h, w, values, loc, cex, lgd) {
  pdf(name, height = 4, width = 3)
  barplot(values, las = 1)
  legend(loc, legend = lgd,
         cex = cex,     # trial & error
         x.intersp = 0, # otherwise, we have a left margin
         trace = TRUE)  # shows user coordinates in the console
  dev.off()
}
name <- "foopdf2.pdf"
foo2(name = name, h = 4, w = 3,
     values = c(8, 2, 3, 3, 1, 2, 3, 1, 9),
     loc = "center", cex = 0.85,
     lgd = c("Text is ok.", "Text is also ok."))
system2("open", args = name, wait = TRUE)

With the additional argument plot = FALSE you could assign all what is needed to a variable:

rect a list with components
• w, h
  positive numbers giving width and height of the legend’s box.
  
• left, top
  x and y coordinates of upper left corner of the box.
text a list with components
• x, y
  numeric vectors of length length(legend), giving the x and y coordinates of the legend's text(s).

Then generate a rectangle which is large enough to contain the text. However, using legend() directly (eventually with x, y coordinates) is much simpler. See the examples at the end of the man page of legend.