<br />
library(ggplot2)<br />
library(grid)<br />
df <- data.frame(a=1:5,b=1:5)<br />
a <- ggplot(df, aes(x=a, y=b)) + geom_point() + labs(title="figure 1")<br />
b <- ggplot(df, aes(x=b, y=a)) + geom_point() + labs(title="figure 2")<br />
grid.newpage()<br />
pushViewport(viewport(layout=grid.layout(1, 2)))<br />
print(a,vp=viewport(layout.pos.row=1, layout.pos.col=1))<br />
print(b,vp=viewport(layout.pos.row=1, layout.pos.col=2))<br />
dev.off()<br />
</p>