R help - Aug 2010 - Greek letters and variable values in lattice plot annotation

I'd like to annotate a lattice plot, e.g. xyplot, with text containing both
Greek letters and variable values. In the base graphics plot command this
can be accomplished with e.g. main
substitute(paste(lambda,"=",var),list(var=var)), where var is a
variable
that contains the value. When I try to do this in xyplot, I get the error
message "object 'lambda' not found". Any ideas on how to do
this in xyplot?
Thanks for the help!

	[[alternative HTML version deleted]]

On Aug 31, 2010, at 11:34 AM, Thomas Maier wrote:
> I'd like to annotate a lattice plot, e.g. xyplot, with text  
> containing both
> Greek letters and variable values. In the base graphics plot command  
> this
> can be accomplished with e.g. main >
substitute(paste(lambda,"=",var),list(var=var)), where var is a
> variable
> that contains the value.
Try wrapping as.expression around that substitute argument. Both of  
these seem to deliver desired results.

 > var=5
 > xyplot(1~1, main = as.expression(bquote(lambda==.(var))))
 > xyplot(1~1, main =  
as.expression(substitute(paste(lambda,"=",var),list(var=var))))
> When I try to do this in xyplot, I get the error
> message "object 'lambda' not found". Any ideas on how to
do this in
> xyplot?
> Thanks for the help!
>
David Winsemius, MD
West Hartford, CT