Re: st: Re: Variable selection

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Fri, 4/3/11, Sherriff, Martyn wrote:
> Rather than write a 'locaI' to include the variables that I
> wish to analyse I have tried to exclude the variables that
> I do not want as follows:
> 
> qui:findname
> foreach v of varlist `r(varlist)'{
>     if "`v'" !="chew" {
>         kwallis `v',by(ur6)
>     }
>}

There is no need for such a loop, see the example below:

*------------- begin example -----------------
sysuse auto, clear

// already exclude string variables
ds, has(type numeric) 

// store remaining variable names in a local
local varl `r(varlist)' 

// store the variables you want to exclude 
// in another local 
local out "foreign rep78" 

// remove the variables names you want to remove
local varl : list varl - out

// check if they are really out
di "`varl'"
*--------------- end example -----------------------
(For more on examples I sent to the Statalist see: 
http://www.maartenbuis.nl/example_faq )

You can read more about this trick and many more by 
going to the helpfile of -macro- and click on the link
to "extended macro functions".

Hope this helps,
Maarten

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

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


      

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