[babel] buffer-wide settings for R graphical header arguments

[Erik Iverson <eriki@ccbr.umn.edu>]

Hello,

You can specify graphical header args in source blocks for R blocks that 
produce graphical output, e.g.:

#+BEGIN_SRC R  :file output.png :width 720

You can also set buffer-wide options with the following syntax, for 
example, with the tangle header argument.

#+PROPERTY: tangle yes

However, this doesn't appear to be working for me if I use, say `width`, 
in the following fashion.

#+PROPERTY: width 720

Are R graphical header arguments supposed to be able to be set buffer-wide?

Thanks!
Erik