st: AW: Find variable with first occurrence of a value in a list of variables

["Martin Weiss" <martin.weiss1@gmx.de>]

<> 



I do not think there is a canned solution, but have you had a look at
-egen-, functions -anymatch-, -anyvalue- and -anycount-? They do offer
partial solutions here.



HTH
Martin

-----Ursprüngliche Nachricht-----
Von: owner-statalist@hsphsun2.harvard.edu
[mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von Mike Lacy
Gesendet: Dienstag, 13. Juli 2010 15:34
An: statalist-digest@hsphsun2.harvard.edu
Betreff: st: Find variable with first occurrence of a value in a list of
variables


I'm looking for a relatively easy way to find, for each observation, 
which variable in a list has the first occurrence of a particular 
value.  I was looking for a built-in solution, but not finding 
something, came up with a "roll your own" solution that seems less 
than ideal, and so am seeking suggestions

// Example data: For each case, find first occurrence of a "1" in a 
list of five variables.
set obs 10
forval i = 1/5 {
    gen byte x`i' = (runiform() > 0.6)
}
local value_of_interest 1
tempvar found
gen byte `found' = 0
gen str varname = ""
foreach v of varlist x1-x5 {
    replace varname  = "`v'" if (!`found') & (`v' == `value_of_interest')
    replace `found' = 1 if (`v' == `value_of_interest')
}
//

I'm interested in a simple and efficient approach to the general 
case, i.e., not assuming that the variable list of interest is 
numbered. Among other things, the looping approach here would seem a 
bit better if there was a way to terminate the search for each 
observation the loop when `found' ==1.

Suggestions?

Regards,
=-=-=-=-=-=-=-=-=-=-=-=-=
Mike Lacy, Assoc. Prof.
Soc. Dept., Colo. State. Univ.
Fort Collins CO 80523 USA
(970)-491-6721   


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