[R] Regexp subexpression
dieter.menne at menne-biomed.de
Sat Mar 25 18:24:04 CET 2006
Gabor Grothendieck <ggrothendieck <at> gmail.com> writes:
> In the third case there is no match so there are no
> substitutions. Handle it separately:
> pat = "^([[:alpha:]]+)([[:digit:]]+)"
> result <- cbind(txt = sub(pat, "\\1", patid), num = sub(pat, "\\2", patid))
> result[regexpr(pat, paid) < 0,] <- NA
Thanks, Gabor, that something like a compressed version of mine. My main
question was if I was missing something obvious, because I found the double sub
messy. I am a surprised that there is not
pat = "^([[:alpha:]]+)([[:digit:]]+)"
returning a list with all subexpressions.
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