st: regular expression or some simpler data extraction method

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

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.  

The string variable is named "phase"

1 PV, 5 CC, 37 WT
101 WT
2 PV, 9 WT
1 WT
38 WT

All I am concerned with is the number directly in front of "WT".  That
number can be 1, 2 or 3 digits.

The closest iteration was:
gen vi_tnum=regexs(1) if regexm(phase, "[ 0-9A-Z]?[\,]?([0-9]+)[ A-Z]+$")

but that produced a result that had its leading digit truncated for any
number with more than one digit.  

Any thoughts, oh brilliant ones?

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



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