[R] ggplot 2 - editing in the "panel_1_1" viewport

Paul Murrell p.murrell at auckland.ac.nz
Tue Sep 30 21:19:55 CEST 2008


Pedro Barros wrote:
> Hi All,
> I am trying to find out how to access the components of a ggplot plot, and I
> found this reply from Paul Murrel
> http://www.nabble.com/navigating-ggplot-viewports-tt14826352.html#a15056223.
> I tried it, and it works.
> However, I am trying to develop some functions that will do the drawing
> "automatically", and usually I will not know the full name of the grob that
> has the layout vp, like "plot.gtree.76". Is there a way that I can repeat
> the same process, without going through the grid.ls step?

Being able to divine the names of grobs (and viewports) is dependent on
the system being used to name the grobs/viewports.  One approach, taken
in lattice for viewports, is to provide a function, e.g.,
trellis.vpname(), that builds a name from salient bits of information,
e.g., panel numbers.  Another important source of information is
documentation of the naming scheme, e.g., for ggplot2, Hadley's


> Thanks,
> Pedro

Dr Paul Murrell
Department of Statistics
The University of Auckland
Private Bag 92019
New Zealand
64 9 3737599 x85392
paul at stat.auckland.ac.nz

More information about the R-help mailing list