st: combining two variables

[Daphna Bassok <dbassok@stanford.edu>]

hi all-

i have a data structure question, and i could use some advice.

suppose i have two variables say a_school and b_school.  the values of 
these two variables are either the same, or one of the two might 
be  missing. i would like to somehow merge these into a single variable- 
say c_school.

if i only had to do this once, it would be quite simple.

gen c_school=b_school
replace  c_school=a_school if c_school==.

done.

however, i have to do this repeatedly.  as in... i have many of these 
pairs. a_size, b_size... a_score, b_score...etc.

i have been trying to figure out a way to do this with the foreach command.

but it doesn't seem to be working out.

does anyone have any suggestions?

any help would be appreciated.

daphna

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