Plot with reversed y-axis and x-axis on top in ggplot2

Question

I\'m trying to get ggplot2 plot with reversed y-axis and x-axis on top. I used scale_y_reverse() to get reversed y-axis but could not figured out h

Answer 1

Now even easier with ggplot v2.2.0:

p1 <- ggplot(data=dfn, aes(x=dose, y=length, group=supp, colour=supp)) + geom_line() + geom_point()
p1 <- p1 + scale_y_reverse() + scale_x_continuous(position = 'top')
print(p1)