st: re: data manipulation

Austin gave an example based on observation offsets. You could also do it with -reshape-:

clear
input x y
1 .
2 .
3 .
. 4
. 5
. 6
end

g int obs = mod(_n-1,3)+1
egen xx=rowtotal(x y)
drop x y
g int group = int((_n-1)/3)
reshape wide xx, i(obs) j(group)
list

Kit Baum, Boston College Economics and DIW Berlin
http://ideas.repec.org/e/pba1.html
An Introduction to Modern Econometrics Using Stata:
http://www.stata-press.com/books/imeus.html

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