st: Referring to elements of a varlist in a program

[Dani Tilley <tilleydani@yahoo.com>]

Hi,

I'm trying to write a program that will automate some commands, but to increase 
its usability I need to include 2 variables in the syntax. I need to figure out 
a way to refer to a user-specified variables and  manipulate them in the body of 
the program. For instance, if the user  were to specify two variables -example 
var1 var2- ,my program would find the mean for each  and divide the sum of the 
means by the standard deviation of the second  variable. (this is just an 
exercise, it doesn't mean anything) 


I've declared the following


program example, rclass
version 10.0
syntax varlist(min=2 max2)

loc m=0
foreach v of varlist `varlist' {
qui su `v',mean
loc m=`m'+`r(mean)'
}

qui su varlist[2] ///I don't know how to refer to this
local sd = `r(sd)'
local final = `m' / `sd'
drop m sd
return local final = `final'

end


Any help is appreciated.

DF Tilley


      
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