Numbers in a string
On Dec 15, 2010, at 6:01 AM, Nick Sabbe wrote:
Hi Felipe,
gsub("[^0123456789]", "", "AB15E9SDF654VKBN?dvb.65")
results in "15965465".
Would that be what you are looking for?
I tried figuring out how to do this from a more positive perspective,
meaning finding a regular expression function that did not require
negating the desired elements, but the best I could do was make a
function that accepted a pattern and then hid the underlying negation:
> pullchar <- function(txt, patt){
if(grepl("\\[", patt)){pattn <- sub("\\[", "\\[\\^", patt)}
else{
pattn<- paste("[^",patt,"]", sep="")}
gsub(pattn, "", txt) #return }
> pullchar("AB15E9SDF654VKBN?dvb.65", "ABD")
[1] "ABDB"
> pullchar("AB15E9SDF654VKBN?dvb.65", "[A-Z]")
[1] "ABESDFVKBN"
> pullchar("AB15E9SDF654VKBN?dvb.65", "[0-9]")
[1] "15965465"
Still learning regex so if there is a "positive" strategy I'm all
ears. ...er, eyes?
David. > > > Nick Sabbe > -- > ping: nick.sabbe at ugent.be > link: http://biomath.ugent.be > wink: A1.056, Coupure Links 653, 9000 Gent > ring: 09/264.59.36 > > -- Do Not Disapprove > > > > > -----Original Message----- > From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org > ] On > Behalf Of Rainer Schuermann > Sent: woensdag 15 december 2010 11:19 > To: r-help at r-project.org > Subject: Re: [R] Numbers in a string > > If your OS is Linux, you might want to look at sed or gawk. They are > very > good and efficient for such tasks. > You need it once or as a part of program? > Some samples would be helpful... > Rgds, > Rainer > > > -------- Original-Nachricht -------- >> Datum: Wed, 15 Dec 2010 16:55:26 +0800 >> Von: Luis Felipe Parra <felipe.parra at quantil.com.co> >> An: r-help <r-help at r-project.org> >> Betreff: [R] Numbers in a string > >> Hello, I have stings which have all sort of characters (numbers, >> letters, >> punctuation marks, etc) I would like to stay only with the numbers in >> them, >> does somebody know how to do this? >> >> Thank you >> >> Felipe Parra >> >> [[alternative HTML version deleted]] >> >> ______________________________________________ >> R-help at r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. > > -- > > ------- > > Windows: Just say No. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help at r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.