Re: st: Using the -if- qualifier with a string variable

[Roger Newson <roger.newson@kcl.ac.uk>]

At 16:15 03/04/2005, Louis wrote:
> Dear All,
> Can the -if- qualifier be used with a string variable? If so, how is it 
> done? I gave the following command, and had the shown result:
> . keep if facility==bir
> bir not found
> r(111);
>
> "facility" is a string variable and "bir" is one of the values "facility" 
> takes.
You should type

keep if facility=="bir"

That way, Stata knows that "bir" is a string value. If you type

keep if facility==bir

then Stata will look for a string variable named bir, and will complain if 
it doesn't find it.

I hope this helps.

Roger






--
Roger Newson
Lecturer in Medical Statistics
Department of Public Health Sciences
Division of Asthma, Allergy and Lung Biology
King's College London

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Opinions expressed are those of the author, not the institution.

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