Thank you Christopher, that is actually very helpful. =) Carol
On Sat, Apr 24, 2010 at 12:13 PM, Christopher W Ryan <cr...@binghamton.edu>wrote: > You should be aware that if you have read the data from your csv file > into an object in R, generally nothing you do with that object in R > will change your original csv file (this is generally a good thing), > until/unless, you save or write something from R to that csv file > (which is sometimes not a good idea, if you want to preserve what your > original data looked like.) > > It would also be helpful if you could post to the list the lines of > code that you used to do whatever you are describing here in words. > This will get you better answers. > > If the dataframe in R into which you read your data is called my.data, > then you could create a new column or variable with a command like > this: > > my.data$newcolumn <- [in here put the expression for your new column] > > for example: > > my.data$newcolumn <- my.data$firstcolumn + my.data$secondcolumn > > On Fri, Apr 23, 2010 at 9:49 PM, Carol Gao <carol.g...@gmail.com> wrote: > > Hi, > > > > I've got a csv format of file. There are seven columns of variables all > > together, and I've used the diff() function to take the differences > between > > the variables in one column. Now I want to add the differences as the 8th > > column variable to the csv file. Is there any way that I can do this? > > > > Thanks in advance. > > > > Carol Gao > > > > [[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. > > > > ______________________________________________ > 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. > [[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.
