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Re: st: How to use functions within variable names


From   Maarten Buis <maartenlbuis@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: How to use functions within variable names
Date   Wed, 17 Aug 2011 09:53:16 +0200

On Wed, Aug 17, 2011 at 3:14 AM, Sdfsdfsadfsf Sdfsdf wrote:
> is it possible to use the result of a function or mathematical operation as a part of a variable name?
>
> Here is a simple example what I want to do
> forvalue i=1(1)2 {
> rename r`i'= r[`i'-1]    // Instead of the operation in the squared brackets there should be the result eg.0 for 1-1
> }

rename r`i' = r`=`i'-1'

See: <http://www.maartenbuis.nl/example_faq/index.html#%60=%27>

> or an more accurate example with variables
>
> forvalue i=1(1)100 {
> replace b_`i'= a[c+`i']
> }
>
> c is a variable with integer values
> The result of c+`i' determines the variable from which the value of b_`i'is taken from
>
>
> eg    `i'=3; c=7;
>         b_3 =a10

Here you need a very different strategy:

*------------- begin example --------------
clear
input str3 b1 str3 b2 c
      foo     bar     8
      bla     bla     1
end

forvalues i=1/2 {
	replace b`i' = "a" + string(c + `i')
}
list
*-------------- end example ---------------
(For more on examples I sent to the Statalist see:
http://www.maartenbuis.nl/example_faq )

Hope this helps,
Maarten

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--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany


http://www.maartenbuis.nl
--------------------------

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