[R] how to get a line plot before/after treatment

[Frank Mattes]

Dear R help-list reader,

I would like to generate a plot which compares to states in a patient 
treatment, before and after. for this reason I have generated a vector
before<-c(1,30,23,40)
and
after<-c(20,10,20,60)
the first element in "before" corresponds to the first element in "after".
I would like and generate a dotplot with
before and after as x-scale, the elements of "before" and "after" on 
the y-scale and the corresponding elements connected with a line.

However, so far I couldn't figure out how to do this in R. If anyone 
as a suggestion, please let me know

Many thanks

Frank
-- 
Frank Mattes, MD			e-mail:	f.mattes at ucl.ac.uk
Department of Virology			fax	0044(0)207 8302854
Royal Free Hospital and 			tel	0044(0)207 8302997
University College Medical School
London