How to draw a line or add a text outside of the plot area in R?

Question

Thank you for reading. I find that I am unable to draw lines/points or add text outside of the plot area. If I draw a line from inside the plot (within the axis) area to the are

Answer 1

The xpd parameter controls where you can draw. Check the current value with par()$xpd and then try setting par(xpd=NA).

From the par help:

 ‘xpd’ A logical value or ‘NA’.  If ‘FALSE’, all plotting is
      clipped to the plot region, if ‘TRUE’, all plotting is
      clipped to the figure region, and if ‘NA’, all plotting is
      clipped to the device region. See also ‘clip’.