[R] Background color(s) for groupedData plot

[Paul, David A]

Thank you both for pointing out that this is a lattice
plot (ie, R's version of Trellis graphics) and therefore
needs something other than par().

I was able to use IE6.0 to search for "trellis" and
find the relevant commands (after using help.start(),
of course).  This brings up another question:

Is there a convenient way to decide whether or not
the generic plot( ) is going to use "regular" or
"trellis" plotting?  I looked at methods(plot) and
didn't find any groupedData plot methods listed, so
perhaps this is the clue?


-david paul