Hi Jim, That is what I ended up doing. Each of my 1000 files has ~1 million rows, and 19 columns and it was taking 85 secs for every file to be just read into R. All I needed to do was replace one column with a particular vector values. So wanted to know if there was a way to do it without reading all the columns. Thanks for your time, Sashi
-----Original Message----- From: jim holtman [mailto:jholt...@gmail.com] Sent: Wednesday, March 23, 2011 11:50 AM To: Sashi Challa Cc: r-help@r-project.org Subject: Re: [R] Modifying a particular column in a tab-delimited file Read the whole file in, modify the column and then write the file back out. On Wed, Mar 23, 2011 at 12:03 PM, Sashi Challa <cha...@ohsu.edu> wrote: > Hello R users, > > Good day!! > > I was wondering if there is a way in R to read in a particular column from a > tab-delimited file, edit it and write it back into the file with all other > columns intact. When I say edit I mean just replacing all the values in that > column. > I know to read a particular column from a file using colClasses option in > read.delim() function. > Is there any such option to write out a column into an already existing file > using write.table() function ?? > > Thanks for your time > > -Sashi > > > [[alternative HTML version deleted]] > > ______________________________________________ > 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. > -- Jim Holtman Data Munger Guru What is the problem that you are trying to solve? ______________________________________________ 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.
