Hannah, If Gen is a factor you can simply build the new factor "on top" of it:
dataframe$Gen<- factor( c('Wynda' , 'A_2' , 'B_1' , 'Wynda' , 'Wynda' , 'OP1_5')[Gen] ) Just make sure the replacement labels are in the same order as levels(Gen). Cheers On Tue, Feb 28, 2012 at 8:39 PM, hannahmaohuang <hannahmaohu...@gmail.com> wrote: > Dear All, > I've been searching relevant topics about replacing values, none seemed to > be applicable to me... > > I have a file with many many varieties, and want to replace some of them > into different names. > I tried various of ways, still don't know how to do that most efficiently.. > Here is part of the example data: > > > Gen Rep > A_1 1 > A_1 2 > A_2 1 > A_2 2 > B_1 1 > B_1 2 > B_3 1 > B_3 2 > OP1_1 1 > OP1_1 2 > OP1_5 1 > OP1_5 2 > > For example, I want to replace A_1, B_3, OP1_1 into different name > "Wynda" > > So that the expected file should become: > > Gen Rep > Wynda 1 > Wynda 2 > A_2 1 > A_2 2 > B_1 1 > B_1 2 > Wynda 1 > Wynda 2 > Wynda 1 > Wynda 2 > OP1_5 1 > OP1_5 2 > > > I have created a link file, which contains two rows, translating which Gen > correlating to which Name. Not sure if this file helps or not, example as > below: > > Column1(Gen) Column2(Name) > A_1 Wynda > A_2 A_2 > B_1 B_1 > B_3 Wynda > OP1_1 Wynda > OP1_5 OP1_5 > > > Though I can replace one by one in excel, since there are too many files and > too many reps, it'll be very time-consuming also easy to make mistakes. > > Please give me any guidance or help in terms of finish this with R. > > Thanks so much ! > > Sincerely > Hannah > > > > -- > View this message in context: > http://r.789695.n4.nabble.com/How-to-replace-the-values-in-a-column-tp4430448p4430448.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. ______________________________________________ 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.