Re: st: Programming question

[David Kantor <dkantor@jhu.edu>]

At 12:00 PM 3/4/2005 -0500, Cameron Hooper wrote:
> A novice programming question. Say I have the following data
>
> id x
> 1  1
> 1  2
> 1  4
> 2  2
> 2  8
> 2  6
> 2  2
>
> I want to write a program to loop through each company (represented by id) 
> and then within each company loop through each observation. Something like:
>
> forvalues i = 1(1)<number of companies> {
>   for values j = 1(1)<number of observations for company `i'> {
>     <do stuff>
>   }
> }
>
> [...]
I might add to my previous message: one way to do the outer loop might be 
(untested, and I have no experience yet with -levels-)...

levels id, local(idlist)
foreach i of local idlist {
  <do stuff>
}

But, again, I guess that looping may be unnecessary.

-- David

David Kantor
Institute for Policy Studies
Johns Hopkins University
dkantor@jhu.edu
410-516-5404
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