Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down at the end of May, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: st: RE: counting number of variables in a varlist


From   Nick Cox <njcoxstata@gmail.com>
To   statalist@hsphsun2.harvard.edu
Subject   Re: st: RE: counting number of variables in a varlist
Date   Thu, 16 Jun 2011 06:54:14 +0100

Sure. I was having a little joke about -x1 x2-.

I don't think there's a best way. Using a global rather than a local
is not usually necessary or particularly good style for something you
only need in a particular context.

Nick

On Thu, Jun 16, 2011 at 12:11 AM, ali hashemi <hashemi@vt.edu> wrote:
> Many thanks for your help. Actually -x1 x2- was just an example. In the main
> problem the number of variables in the varlist is not pre-determined and
> depends on the syntax that user uses. So I guess the best way to do it would
> be:
>
> global count: word count `varlist'
>
> thanks again
> Ali
>
>
> After
>
> . describe <varlist>
>
> r(k) contains the number of variables in <varlist>.
>
> After
>
> unab vars : <varlist>
> di `: word count `vars''
>
> you get to see how many variables there are.
>
> If you go
>
> . di c(k)
>
> you get to see how many variables there are in memory.
>
> With -x1 x2- I can count them by hand and get 2 consistently, but this may
> not be a skill taught nowadays.
>
> Nick
> n.j.cox@durham.ac.uk
>
> ali hashemi
>
> I would like to count the number of variables in a varlist. The way I manage
> to do this is as follows:
>
> local i=0
> foreach var in x1 x2 {
> local i=`i'+1
> }
>
> I was wondering if there is any built-in command which does the same thing.
>
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index