Re: st: loop that refers to global

[David Kantor <dkantor@jhu.edu>]

At 03:03 PM 6/24/2003 -0700, Bogdan Savyich wrote:
> I want to write a do-file that uses loops to refer to some global macros.
> Global macros define different variables that I want to use in different
> regressions.  However, when I run program I receive an error.  Example of
> the do-file is goes like this:
>
> version 7
> global cov1="var3"
> global cov2="var3 var4"
> global cov3="var3 var4 var5"
>
> local i=1
> while `i'<=3 {
>         logistic y var1 var2 $cov`i'
>         local i=`i'+1
> }
>
> After I run this do file it gives an error:
>
> 1 invalid name
> r(198);

I think that what you need is to put braces in the appropriate places.  Try 
this:
 logistic y var1 var2 ${cov`i' }

Braces force the order of macro binding.  Without them, Stata tries to 
first decode $cov  -- which is nothing.  Then it decodes `i' which is "1". 
That's the source of your error.  The braces will force "cov`i'" to be 
decoded first, which is what you want.

-- David

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

*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/