box plot

["Zheng_Jenny" <Zheng_Jenny@Allergan.com>]

Dear Splus-user,

 

I have a dataset including variables: subject id (n=80), treatment (n=4), visit number (from 1 to7), and response. I would like to make a boxplot of response split by treatment for each visit in the same plot.  

 

The data set can be generated using the command below:

 

data_data.frame(id=rep(1:80,each=7),trt=rep(c(0,2,4,8),each=7*20),visit=rep(1:7,80),response=rnorm(560,20,2))

 

Any inputs will be greatly appreciated? Thanks,

Many thanks,

 

Jenny