Hi. You can do something like this:
df <- read.table(textConnection(" 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"),header=TRUE,stringsAsFactors=FALSE) str(df) #adding a new column cbind(df,ncol = ifelse(df$Gen=="A_1","Wynda",ifelse(df$Gen=="B_3","Wynda",df$Gen))) #replacing exisiting values df$Gen[df$Gen=="A_1" | df$Gen=="B_3"] <- "Wynda" df Andrija On Wed, Feb 29, 2012 at 7:06 AM, ilai <ke...@math.montana.edu> wrote: > 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. ______________________________________________ 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.