Single line chart with a grouping variable

[Hossein Jebeli]

How can I plot the following series in one plot, without specifying the grouping variable (i.e., province) one by one?

Province	year	n
A	2010	1
A	2011	2
A	2012	3
B	2010	4
B	2011	5
B	2012	6

graph twoway line n year if province== "A" || line n year if province== "B", legend(label(1 "A ") label(2 "B"))

[Nick Cox]

Here are two solutions. Naturally it's immediate and trivial that a single plot is likely to work well for two series.

That is not at all obvious if the real number of provinces here is more like 20, or 200....

clear
input str1 Province    year    n
A    2010    1
A    2011    2
A    2012    3
B    2010    4
B    2011    5
B    2012    6
end 

encode Province, gen(province)
xtset province year 
xtline n, overlay name(G1, replace)

* sepscatter is from SSC 
sepscatter n year, recast(line) separate(Province) name(G2, replace)