Regular expressions are in much more widespread use than merely R... and there are correspondingly more resources for learning than just R-help. Please do make use of them. Here are a couple that googling "regex character set carat" found:
https://www.regular-expressions.info/charclass.html https://stackoverflow.com/questions/23352038/regex-excluding-specific-characters On September 13, 2019 3:59:07 AM PDT, Christofer Bogaso <bogaso.christo...@gmail.com> wrote: >A quick question. > >Could you please explain the -- [^}]* -- part in finding the pattern? > >On Fri, Sep 13, 2019 at 12:19 AM Bert Gunter <bgunter.4...@gmail.com> >wrote: >> >> >> You can't use the same regex for str_extract_all as I used for sub >(or gsub, which is what is required here)! If you do this sort of thing >a lot, you *must* learn more about regex's. >> >> Anyway, this will do what you want I think: >> >> z <- paste("ab{cd$ }ed", "ab{cad$ }ed", collapse = " ") ## just for >readability >> >> > str_extract_all(z,"\\{[^}]*\\}") >> [[1]] >> [1] "{cd$ }" "{cad$ }" >> >> Cheers, >> Bert >> >> On Thu, Sep 12, 2019 at 10:12 AM Christofer Bogaso ><bogaso.christo...@gmail.com> wrote: >>> >>> Thanks Bert, >>> >>> This works, but if in my text there are more than one patterns then >>> fails to generate desired result. >>> >>> library(stringr) >>> str_extract_all(paste("ab{cd$ }ed", "ab{cad$ }ed", collapse = " "), >>> ".*(\\{.*\\}).*") >>> >>> This generates below - >>> >>> [[1]] >>> >>> [1] "ab{cd$ }ed ab{cad$ }ed" >>> >>> I was expecting I would get a vector of length 2 with desired >pattern. >>> >>> Where did I make any mistake? >>> >>> Thanks, >>> >>> On Thu, Sep 12, 2019 at 10:29 PM Bert Gunter ><bgunter.4...@gmail.com> wrote: >>> > >>> > > sub(".*(\\{.*\\}).*", "\\1","ab{cd$ }ed") >>> > [1] "{cd$ }" >>> > >>> > Use ".+" instead of ".*" within the {} if you don't want to return >empty {}'s. >>> > >>> > You might wish to use the stringr package for string matching and >manipulation, as it provides a more user friendly and consistent >interface to these tasks. >>> > >>> > >>> > Bert Gunter >>> > >>> > "The trouble with having an open mind is that people keep coming >along and sticking things into it." >>> > -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip ) >>> > >>> > >>> > On Thu, Sep 12, 2019 at 9:31 AM Christofer Bogaso ><bogaso.christo...@gmail.com> wrote: >>> >> >>> >> Hi, >>> >> >>> >> I am wondering on what is the correct way to select a pattern >which goes as - >>> >> >>> >> {"(any character with any length)"} >>> >> >>> >> The expressions " {" " and " "} " both are included in the >pattern. >>> >> >>> >> For example, the lookup of the above pattern in the text " >>> >> {"asaf455%"}57573blabla " will result in {"asaf455%"} >>> >> >>> >> Any help will be highly appreciated. >>> >> >>> >> Thanks, >>> >> >>> >> ______________________________________________ >>> >> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >>> >> 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@r-project.org mailing list -- To UNSUBSCRIBE and more, see >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. -- Sent from my phone. Please excuse my brevity. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
