The key here is to set the 'ylim' argument so that the range of the y
axis is rev()ersed.
# Set 'x'
x <- 0:10
# set xlim and ylim
# set ylim to rev() the range() of 'x'
plot(x, xlim = c(0, 10), ylim = rev(range(x)))
If you actually want to have the 'x' axis value of 0 in the lower left
hand corner as is shown below, you need to adjust the axis style, which
by default ("r") is expanded by 4% of the range of the x and y values
(or xlim and ylim). So use: