see help inlist()
It only works with up to 10 strings (which your example exactly meets)
M Blasnik
----- Original Message ----- From: "Michael McCulloch" <[email protected]>
To: "Statalist" <[email protected]>
Sent: Friday, September 14, 2007 10:01 AM
Subject: st: global keys
Dear Statalist members,
I have a dataset which contains a variable <site_02> containing a 
long list of tumor ID codes, from which I want to keep ten:
C180 through C189.
Is there a less labor-intensive way to do the following:
keep if site_02=="C180" |  site_02=="C181" |  site_02=="C182" |  ///
site_02=="C183" |  site_02=="C184" |  site_02=="C185" | ///
site_02=="C186" |  site_02=="C187" |  site_02=="C188" | site_02=="C189"
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