Question

I have three plots which I would to arrange in a single window. I can arrange similar-sized plots on a regular 2*2 grid using par(mfrow = c(2, 2)):

par(mfrow = c(2, 2))
plot(1:10, main = "plot1")
plot(10:1, main = "plot2")
plot(rnorm(10), main = "plot3")

However, I want to position “plot1” and “plot2” beside each other on the top row, and “plot3” below them, centered horizontally. How can I achieve this?

Answer 1

You probably want layout, you can set up pretty complex grids by creating a matrix.

m <- matrix(c(1, 0, 1,  3, 2, 3, 2, 0), nrow = 2, ncol = 4)
##set up the plot
layout(m)
## now put out the 3 plots to each layout "panel"
plot(1:10, main = "plot1")
plot(10:1, main = "plot2")
plot(rnorm(10), main = "plot3")

Use layout.show to see each panel.

Print out the matrix to see how this works:

 m
      [,1] [,2] [,3] [,4]
 [1,]    1    1    2    2
 [2,]    0    3    3    0

There are 1s for the first panel, 2s for the second, etc. 0s for the “non-panel”.

See help(layout).