Hi all,> diff_operator <- "\\(" > strsplit(cond, diff_operator)[[1]] [1] "andsin" "log_angle_1_4)"> diff_operator <- "\\sin(" > strsplit(cond, diff_operator)Error in strsplit(cond, diff_operator) : invalid regular expression '\sin(', reason 'Missing ')'' When I am going to split with "(" it?s working fine but when i want use "sin(" this is not working. I understand that, I am missing something can anybody please point me. Thanks for your help. Thanks, Bharat ----- Bharat Warule Pune -- View this message in context: http://r.789695.n4.nabble.com/strsplit-with-invalid-regular-expression-tp4648857.html Sent from the R help mailing list archive at Nabble.com.
> strsplit(")asdasdsin(abcd)", "sin\\(")[[1]] [1] ")asdasd" "abcd)">On Thu, Nov 8, 2012 at 12:39 PM, Bharat Warule <bwarule@gmail.com> wrote:> Hi all, > > > diff_operator <- "\\(" > > strsplit(cond, diff_operator) > [[1]] > [1] "andsin" "log_angle_1_4)" > > > diff_operator <- "\\sin(" > > strsplit(cond, diff_operator) > Error in strsplit(cond, diff_operator) : > invalid regular expression '\sin(', reason 'Missing ')'' > > When I am going to split with "(" it’s working fine but when i want use > "sin(" this is not working. > I understand that, I am missing something can anybody please point me. > Thanks for your help. > > Thanks, > Bharat > > > > ----- > Bharat Warule > Pune > -- > View this message in context: > http://r.789695.n4.nabble.com/strsplit-with-invalid-regular-expression-tp4648857.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@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. >-- Ulrich Staudinger, Managing Director and Sr. Software Engineer, ActiveQuant GmbH P: +41 79 702 05 95 E: ustaudinger@activequant.com http://www.activequant.com Connect online: https://www.xing.com/profile/Ulrich_Staudinger<https://www.xing.com/profile/Ulrich_Staudinger> [[alternative HTML version deleted]]
HI, cond<-"andsin(log_angle_1_4)" ?diff_operator<-"sin\\(" ?strsplit(cond,diff_operator) #[[1]] #[1] "and"??????????? "log_angle_1_4)" A.K. ----- Original Message ----- From: Bharat Warule <bwarule at gmail.com> To: r-help at r-project.org Cc: Sent: Thursday, November 8, 2012 6:39 AM Subject: [R] strsplit with invalid regular expression Hi all,> diff_operator <- "\\(" > strsplit(cond, diff_operator)[[1]] [1] "andsin"? ? ? ? "log_angle_1_4)"> diff_operator <- "\\sin(" > strsplit(cond, diff_operator)Error in strsplit(cond, diff_operator) : ? invalid regular expression '\sin(', reason 'Missing ')'' When I am going to split with "(" it?s working fine but when i want use "sin(" this is not working. I understand that, I am missing something can anybody please point me. Thanks for your help. Thanks, Bharat ----- Bharat Warule Pune -- View this message in context: http://r.789695.n4.nabble.com/strsplit-with-invalid-regular-expression-tp4648857.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.
In R, the source code representation of a special character uses the \ as an escape character to begin a special character sequence. For example, "\n" is a single newline character. Because backslash has this special meaning, to represent a single backslash character one must escape it: "\\" looks like two backslashes, but in computer memory it is only one character. R is not the only software that uses the backslash as an escape character: the syntax of regular expressions handled by the regex library also does, but it uses the backslash to SUPPRESS special meaning. In your first regex you pass a string containing a backslash followed by a left paren, which tells it to treat the ( as a character to be searched for, not a grouping character that defines a substring to "remember" for backreferencing. In your second regex you tell it that the letter s should be treated as a normal character (which it is anyway), but the ( retains its special meaning that requires a matching ) in the regex. I suspect that what you wanted was "sin\\(", which gives sin\( to the regex library. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnewmil at dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. Bharat Warule <bwarule at gmail.com> wrote:>Hi all, > >> diff_operator <- "\\(" >> strsplit(cond, diff_operator) >[[1]] >[1] "andsin" "log_angle_1_4)" > >> diff_operator <- "\\sin(" >> strsplit(cond, diff_operator) >Error in strsplit(cond, diff_operator) : > invalid regular expression '\sin(', reason 'Missing ')'' > >When I am going to split with "(" it?s working fine but when i want use >"sin(" this is not working. >I understand that, I am missing something can anybody please point me. >Thanks for your help. > >Thanks, >Bharat > > > >----- >Bharat Warule >Pune >-- >View this message in context: >http://r.789695.n4.nabble.com/strsplit-with-invalid-regular-expression-tp4648857.html >Sent from the R help mailing list archive at Nabble.com. > >______________________________________________ >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.