R: Read multiple files and label them based on the file name

Question

I have a folder with about 400 files with the same structure. Each of these file contains 4 columns with no header, corresponding to 4 climate variables. I would need to inc

Answer 1

You could put all your files in a new folder/directory, and then create a loop using list.files:

all.dfs <- list()
for(filename in list.files("some_dir")) {
   all.dfs[[length(all.dfs) + 1]] <- read.table(filename, ...) 
   # put in read.table call the appropriate arguments, including column names for the existing data in the files
   all.dfs[[length(all.dfs)]]$CODE_PLOT <- sub(".*P(\\d*)C(\\d*)\\.csv", "\\1", filename)
   all.dfs[[length(all.dfs)]]$CODE_COUNTRY <- sub(".*P(\\d*)C(\\d*)\\.csv", "\\2", filename)
}

Then merging everything into one dataframe...

big.df <- do.call(rbind, all.dfs)

Haven't tested it but feel free to ask questions in comment.