Hi > > On Wed, 5 Oct 2011, Petr PIKAL wrote: > > > Hm. I seldom use such approach. In your original request you said you want > > split your data to smaller data frames based on sites > > Petr, > > I need the additional information in the database, too.
But you do not loose them, your data frame is cut according to sites variable and put into a list see > iris.spl<- split(iris, iris$Species) > str(iris.spl) List of 3 $ setosa :'data.frame': 50 obs. of 5 variables: ..$ Sepal.Length: num [1:50] 5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ... ..$ Sepal.Width : num [1:50] 3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ... > > > From what we know it is difficult to say if there is some common feature > > in site variable. If it is organised like > > XY-N > > you can simply make new variable from first two letters > > Unfortunately, the site designations are not so uniform. As I went through > the process of re-doing the data I discovered this lack of consistency > resulting in duplicate records because one site had been designated XX-n and > XXn. Had to clean those up, too. > > > sites <- substr(chemdata$site,1,2) Which would not matter if the first two letters designates required grouping variable I called sites Regards Petr > > > > then you can split your data frame according to sites > > > > chem.spl <- split(chemdata, sites) > > > > and do anything with your splitted data frames organised in list > > First thing this morning I'm upgrading to 2.13.2 and hoping that this > fixes an issue that just showed up yesterday afternoon: not being able to > access function help pages. For example, I tried ?subset and ?split because > I thought the latter is really what I want, yet R told me no help was found. > Strange; it was there a week ago. > > Thanks, > > Rich > > ______________________________________________ > 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.