Re: st: RE: Question about a loop

[Cameron Hooper <chooper@umich.edu>]

Hi

> I don't know what
>
> local x 1
>
> is doing here, but it seems irrelevant anyway.

A typo. I meant to type: local i 1. This is to initiate `i' for the 
first iteration of the loop.


> One way to do this is
>
> forval i = 1/10 {
> 	gen op`i' = sum(ret) if inlist(num`i',-1,0,1)
> }
Thanks. I forgot to add that I do not know how many num* variables I 
need to loop over. They are created by an earlier <reshape> command. I 
should have mentioned this in my original post. Your second suggestion 
does not need to know the number of num* variables and is exactly what 
I was looking for.


> Another way to do it is
>
> foreach v of var num* {
> 	local V : subinstr local v "num" "op"
> 	gen `V' = sum(ret) if inlist(`v',-1,0,1)
> }
That's the go. Thanks.

Cameron

> Nick
> n.j.cox@durham.ac.uk
>
> Cameron Hooper
>
> > Say I have 10 variables named: num1, num2, ..., num10. I want to loop
> > over these variables and create 10 new ones named: op1, op2,
> > ..., op10.
> > The following works:
> >
> > local x 1
> > foreach var of varlist num* {
> > 	gen op`i' = sum(ret) if inlist(num`i',-1,0,1)
> > 	local i = `i' + 1
> > }
> >
> > I was originally thinking of accessing each of the num* variable's
> > name, extracting the last digit and appending this to the
> > stub 'op' and
> > thus create a new variable. But I don't know to access a variables
> > name. Can such a thing be done? Can anyone suggest a better way of
> > executing this code?
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