[R] How to plot two dataset in one fig?

[Wei Qiu]

Hi all,

I am new in R tool. I would like to plot two dataset in in fig.

Here is what I did for both a and b data sets

jpeg(file="a.jpeg")
dat<-read.table('a', header=F, sep=',') 
dim(dat)
y<-dat[,1]
y<-y[!is.na(y)]
plot(y);lines(lowess(y, f=0.05), col = 
("red"), lwd=5)
dev.off

Two questions: 
1. How I can save this lowess smooth data?
2. Once I have the smooth a and b data, How I can put two smooth data sets 
in one fig even they have different Y ranger value?

Any input will be greatly appreciated.

Lucy