Another question, How do I extract ID based on the third and fourth letter:
I have for example, AA14004, AB15035, CB14024, PA14009, PA14009 etc I would like to extract ID no. of AB14..., CB14..., PA14... On Mon, Mar 13, 2017 at 12:37 PM, roslinazairimah zakaria < roslina...@gmail.com> wrote: > Hi Bert, > > Thank you so much for your help. However I don't really sure what is the > use of y values. Can we do without it? > > x <- as.character(FKASA$STUDENT_ID) > y <- c(1,786) > My.Data <- data.frame (x,y) > > My.Data[grep("^AA14", My.Data$x), ] > > I got the following data: > > x y > 1 AA14068 1 > 7 AA14090 1 > 11 AA14099 1 > 14 AA14012 786 > 15 AA14039 1 > 22 AA14251 786 > > On Mon, Mar 13, 2017 at 11:51 AM, Bert Gunter <bgunter.4...@gmail.com> > wrote: > >> 1. Your code is incorrect. All entries are character strings and must be >> quoted. >> >> 2. See ?grep and note in particular (in the "Value" section): >> >> "grep(value = TRUE) returns a character vector containing the selected >> elements of x (after coercion, preserving names but no other >> attributes)." >> >> >> 3. While the fixed = TRUE option will work here, you may wish to learn >> about "regular expressions", which can come in very handy for >> character string manipulation tasks. ?regex in R has a terse, but I >> have found comprehensible, discussion. There are many good gentler >> tutorials on the web, also. >> >> >> Cheers, >> Bert >> >> 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 Sun, Mar 12, 2017 at 8:32 PM, roslinazairimah zakaria >> <roslina...@gmail.com> wrote: >> > Dear r-users, >> > >> > I have this list of student ID, >> > >> > dt <- c(AA14068, AA13194, AE11054, AA12251, AA13228, AA13286, AA14090, >> > AA13256, AA13260, AA13291, AA14099, AA15071, AA13143, AA14012, AA14039, >> > AA15018, AA13234, AA13149, AA13282, AA13218) >> > >> > and I would like to extract all student of ID AA14... only. >> > >> > I search and tried substrt, subset and select but it fail. >> > >> > substr(FKASA$STUDENT_ID, 2, nchar(string1)) >> > Error in nchar(string1) : 'nchar()' requires a character vector >> >> subset(FKASA, STUDENT_ID=="AA14" ) >> > [1] FAC_CODE FACULTY STUDENT_ID NAME PROGRAM KURSUS >> > CGPA ACT_SS ACT_VAL ACT_CS ACT_LED ACT_PS >> > ACT_IM >> > [14] ACT_ENT ACT_CRE ACT_UNI ACT_VOL... >> > >> > Thank you so much for your help. >> > >> > How do I do it? >> > -- >> > *Roslinazairimah Zakaria* >> > *Tel: +609-5492370; Fax. No.+609-5492766* >> > >> > *Email: roslinazairi...@ump.edu.my <roslinazairi...@ump.edu.my>; >> > roslina...@gmail.com <roslina...@gmail.com>* >> > Faculty of Industrial Sciences & Technology >> > University Malaysia Pahang >> > Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia >> > >> > [[alternative HTML version deleted]] >> > >> > ______________________________________________ >> > 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/posti >> ng-guide.html >> > and provide commented, minimal, self-contained, reproducible code. >> > > > > -- > *Roslinazairimah Zakaria* > *Tel: +609-5492370 <+60%209-549%202370>; Fax. No.+609-5492766 > <+60%209-549%202766>* > > *Email: roslinazairi...@ump.edu.my <roslinazairi...@ump.edu.my>; > roslina...@gmail.com <roslina...@gmail.com>* > Faculty of Industrial Sciences & Technology > University Malaysia Pahang > Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia > -- *Roslinazairimah Zakaria* *Tel: +609-5492370; Fax. No.+609-5492766* *Email: roslinazairi...@ump.edu.my <roslinazairi...@ump.edu.my>; roslina...@gmail.com <roslina...@gmail.com>* Faculty of Industrial Sciences & Technology University Malaysia Pahang Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia [[alternative HTML version deleted]] ______________________________________________ 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.