Multiple plots with different titles using ggplot lapply…

parameters = data.frame(p1=letters[1:5], p2=round(rnorm(5),2))
l = replicate(5, data.frame(x=1:10, y=rnorm(10)), simplify=FALSE)
names(l) = do.call(paste, c(parameters, sep=","))
 
plot_one = function(x)
  ggplot(data = l[[x]]) + geom_path(aes(x, y)) +
   opts(title = x)
 
plots = lapply(names(l), plot_one)
 
do.call(gridExtra::grid.arrange, plots)