RE: st: regular expression or some simpler data extraction method

["Ben Hoen" <bhoen@lbl.gov>]

Thanks again Mathew & Brendan.

I realized that I had changed the variable name in the meantime to
"phase_description", which was causing the type mismatch error.

This syntax worked great!

gen vi_tnum = regexs(1) if regexm(phase_description, "([0-9]+) WT$") 


Ben Hoen
LBNL
Office: 845-758-1896
Cell: 718-812-7589


-----Original Message-----
From: Ben Hoen [mailto:bhoen@lbl.gov] 
Sent: Wednesday, November 16, 2011 3:22 PM
To: statalist@hsphsun2.harvard.edu
Subject: Re: st: regular expression or some simpler data extraction method

Thanks Mathew.

That didn't seem to work.  I am getting a "type mismatch" error.

Based on your first response I also tried:

gen vi_tnum = regexs(1) if regexm(phase, "[\, ]?([0-9]+) WT$")
and
gen vi_tnum = regexs(1) if regexm(phase, "[\, ]?([0-9]+)[ WT]$")

and got the same "type mismatch" error, so maybe they are related.

I tried these because WT is always the end of the string, therefore any
comma would necessarily precede the digits and the WT.  Maybe that was not
clear originally.

Ben




Ben Hoen
Principal Research Associate
Lawrence Berkeley National Laboratory
Office: 845-758-1896
Cell: 718-812-7589
bhoen@lbl.gov
http://eetd.lbl.gov/ea/emp/staff/hoen.html


Re: st: regular expression or some simpler data extraction method
________________________________________
From
  Matthew White <mwhite@poverty-action.org>
To
  statalist@hsphsun2.harvard.edu
Subject
  Re: st: regular expression or some simpler data extraction method
Date
  Wed, 16 Nov 2011 15:01:27 -0500
________________________________________
Hi Ben,

Scratch that; the "[ ,]?" isn't a good idea. The following should work
as long as there aren't codes other than "WT" that start with "WT":

gen vi_tnum = substr(regexs(0), 1, strpos(regexs(0), " ") - 1) if
regexm(phase, "[0-9]+ WT[ ,]?")
destring vi_tnum, replace



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