Color code Scatter Plot.......

["Khan, Sohail" <khan@cshl.edu>]

Dear S-plus users,
I have a data frame something like:
Chr    X        Y
1       10       5
1        8.5     12
1         6       3
2         15      22
2         25      10
2         9         5
3         10       12
3         29       41


I want to create a scatter plot of X,Y, "color coded" based on the column Chr.  
I.E. chr1=red,chr2=green, chr3=yellow, so on.......
Can this be done in S-PLUS??  I would appreciate your help.
Thanks.

Sohail Khan
Scientific Programmer
COLD SPRING HARBOR LABORATORY
Genome Research Center
500 Sunnyside Boulevard
Woodbury, NY 11797
(516)422-4076