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

[brendan.halpin@ul.ie (Brendan Halpin)]

On Wed, Nov 16 2011, Ben Hoen wrote:

> I have a number of possible string variations from which I am trying to
> extract a portion of, and am having trouble figuring out the correct regular
> expression, or, for that matter, if I can punt and use another (hopefully
> simpler) expression.  

Your regex doesn't need to describe the whole string. Assuming " WT" is
the end of each example, the following should work:

|. input str20 phase
|
|                    phase
|  1. "1 PV, 5 CC, 37 WT"
|  2. "101 WT"
|  3. "2 PV, 9 WT"
|  4. "1 WT"
|  5. "38 WT"
|  6. end
|
|. 
|. gen nwt = real(regexs(1)) if regexm(phase,"([0-9]+) WT$")
|
|. 
|. list
|
|     +-------------------------+
|     |             phase   nwt |
|     |-------------------------|
|  1. | 1 PV, 5 CC, 37 WT    37 |
|  2. |            101 WT   101 |
|  3. |        2 PV, 9 WT     9 |
|  4. |              1 WT     1 |
|  5. |             38 WT    38 |
|     +-------------------------+


Brendan
-- 
Brendan Halpin,   Department of Sociology,   University of Limerick,   Ireland
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