I believe Wu Gong has given you a solution. As a note you were probably reading in the first two columns as either factors or characters and the last one as numeric. You might want to try it again and then do a str() on the resulting data.frame to see what was happening.
It can be confusing to discover that you have factor rather than character data in the data.frame. :) --- On Thu, 8/5/10, karena <dr.jz...@gmail.com> wrote: > From: karena <dr.jz...@gmail.com> > Subject: [R] a question about 'read.table' with or without > 'read.table'.(urgent) > To: r-help@r-project.org > Received: Thursday, August 5, 2010, 12:32 AM > > Hi, I've got a quite tricky question. > I have a txt file, named 'temp.txt', as the following: > snp1 snp2 > snp3 > AA 00 > 00 > GG GG > 00 > 00 AA > 00 > > I want to read the file into R. > 1) when I use 'read.table' without 'header=T' option, > > temp <- read.table('temp.txt') > # I got > > temp > V1 V2 V3 > 1 snp1 snp2 snp3 > 2 AA 00 00 > 3 GG GG 00 > 4 00 AA 00 > > 2) If I include the 'header=T' option, > > temp <- read.table('temp.txt', header=T, as.is=T) > # I got > > temp > snp1 snp2 snp3 > 1 AA 00 0 > 2 GG GG 0 > 3 00 AA 0 > > The difference is for 'snp3', we can see, in 1) the values > for snp3 are all > '00', while in 2) the values are all '0'. > How can I keep the original > values for snp3 as '00', meanwhile get the 'headers' or say > the colnames as > 'snp1 snp2 > snp3'? > > thank you very much, > > karena > > -- > View this message in context: > http://r.789695.n4.nabble.com/a-question-about-read-table-with-or-without-read-table-urgent-tp2314423p2314423.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.