Hello, Try the following.
# Make some data alldata <- list(matrix(rnorm(12), ncol=3), matrix(sample(100), ncol=10)) (alldata <- lapply(alldata, function(x){colnames(x) <- c("Name", LETTERS[2:ncol(x)]); x})) # This does the trick all.order <- lapply(alldata, function(x) order(x[, "Name"])) lapply(seq.int(length(alldata)), function(i) alldata[[i]][all.order[[i]], ]) Hope this helps, Rui Barradas BustedAvi wrote > > Dear R help list, > > I am very new to R and I apologize in advance if this has been answered > before. I have done my best to google/R search what I need but no luck. > Here is what I am attempting: > > I have hundreds of .csv files that I need to sort based on a single column > of alphanumeric data. All of the files contain matrices that have > identical dimensions and headers, however the data table doesn't begin > until the 74th line in each file. Doing some searching, I have been able > to create an object with elements consisting of each file in the folder > containing the targets (please note this is my working directory): > > filenames<-list.files() > alldata<-lapply(filenames, read.csv, skip=73, header=TRUE) > > At this point I believe I have created an object with N elements (where > N=# > files in the wd), each containing the matrix I am attempting to sort. I > am > completely lost as to how I can sort each matrix based on a single column > (say, "Name") and then either overwrite the source files or write to a new > directory all of the sorted data. I half wonder if I should be creating > individual objects for each file that I read in, but I haven't been able > to > figure this out either. Please note that I am trying to sort these files > individually - would a loop be more efficient? > > I appreciate the help, > BustedAvi > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@ 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. > -- View this message in context: http://r.789695.n4.nabble.com/Sort-across-multiple-csv-tp4630531p4630537.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.