pairs() equivalent in ggplot2?

Question

Is it possible to plot a matrix of scatter plots with ggplot2, using ggplot's nice features like mapping additional factors to color, shape etc. and adding smoother?

I am thinking about something similar to pairs().

Answer 1

Yup it is. Just take a look at facets / faceting. This should do the job if I understood you correctly.

use something like:

 yourplotobject +facet_grid(variable~variable)

here's a similar thread with some examples, plus you might also want to try plotmatrix:

  library(ggplot2)
  data(mtcars)
  plotmatrix(mtcars[,1:3])

to me mpg (first column in mtcars) should not be a factor. I haven't checked it, but there's no reason why it should be one. However I get a scatter plot :)

HTH