[R] Remove all box around a plot except bottom line (base graphics)

[Duncan Murdoch]

On 2024-11-28 8:36 a.m., Michael Dewey wrote:
> To make the plot clearer I have removed the axes but I wish to remove
> all the boz except the bottom horizontal line. Using the bty parameter
> does not seem to enable me to just leave the horizontal line at the
> foot. I can get the "l" version to remove everything except the left
> hand side and the base. I could also remove the entire box but that
> looks odd. Am I reading the documentation incorrectly or is it really
> impossible?
> 

It's not something that `bty` can specify or `box()` can do, but you can 
draw a line using lines() or segments().  For example:

  plot(rnorm(100), yaxt="n", bty="n")
  usr <- par("usr")
  lines(usr[c(1,2)], usr[c(3,3)], xpd = TRUE)

You might not even need the lines() call if you don't care how far the 
axis extends.

Duncan Murdoch