st: trajectory graph can not come out line

[Q X <xu.qi.102@gmail.com>]

Hi there,

I follow the method of file I attached below. But on last command,
“twoway () () (line x y)” there is no line connecting the dots on my
graph. I can not figure out why it happens. My dataset is strongly
balanced panel data with years 1960,1970,1980,1990,2000.

Thanks.
Qi

Command on website:
*trajectory2.do file for Stata 10.0
use cd4.dta, clear
egen newid=group(id)
sum newid
drop id
rename newid id
gen timedays=round(time*365.25,1)
sort id timedays
egen cd4mean = mean(count), by(id)
list id count cd4mean in 1/10
sort id
quietly by id: replace cd4mean=. if (_n > 1)
egen rnk=rank(cd4mean)
local i = 1
while `i' <= 7{
     gen sub`i' =(rnk == `i'*25)
     sort id timedays
     quietly by id: replace sub`i'=sub`i'[1]
     gen cd4l`i' = count if (sub`i')
     drop sub`i'
     local i=`i'+1
}
ksm count timedays, lowess gen(cd4smth) nograph
twoway (scatter count timedays) (scatter cd4smth timedays) (line
cd4l1-cd4l7 timedays)

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