Example of a precomputed vignette

This is an example of a precomputed vignette:

set.seed(1234)
tbl <- data.frame(x = runif(10), y = runif(10))
plot(x = tbl$x, y = tbl$y)

plot of chunk plot

Another plot

plot(x = tbl$y, y = tbl$x)

plot of chunk plot2