st: using regex

[Rijo John <rmjohn@gmail.com>]

Hi statlist,

I have a string variable (code) with state and county codes merged.
For example, the observation 12001 indicate that the first 2 digits
are state codes and the remaining 3 digits are county codes. I want to
create a new variable (fips) only with the state code.  I use the
following

gen fips = regexs(0) if(regexm(code, "[0-9][0-9]"))

and it works fine when the code contains 5 digits. But if a particular
state code is only 1 digit and thereby the string "code" only has a
total of 4 digits the trick above does not work. In such cases I want
to only extract the first digit.
Can someone help?

Thanks.
Rijo.
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