Taken from: http://www.cookbook-r.com/Graphs/Multiple_graphs_on_one_page_(ggplot2)/
multiplot(..., plotlist = NULL, cols = 1, layout = NULL)
| ... | object can be passed in |
|---|---|
| plotlist | plotlist |
| cols | number of columns in layout |
| layout | a matrix specify the layout. If present, 'cols' is ignored |
plots