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Re: st: create unique random number variable


From   Stas Kolenikov <skolenik@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: create unique random number variable
Date   Tue, 24 Apr 2012 09:43:07 -0500

On Tue, Apr 24, 2012 at 4:37 AM, raoul reulen <r.c.reulen@gmail.com> wrote:
> Hello
>
> I'm trying to generate a random number variable like this:
>
> .set seed 12345
> .gen x = int(1000*uniform())
>
> However, the random numbers in variable x are not unique. Is there a
> way to ensure they are unique?

clear
set obs 400
* this is your sample size

generate uu = int(1000*uniform())
bysort uu: generate byte nonuniq = _n > 1
sum nonuniq, mean
while r(max) > 0 {
bysort uu: replace uu = int(1000*uniform()) if _n > 1
bysort uu: replace nonuniq = _n > 1
sum nonuniq, mean
}
drop nonuniq

-- 
Stas Kolenikov, also found at http://stas.kolenikov.name
Small print: I use this email account for mailing lists only.
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