[R] rbind common header to file list

Jeff Newmiller jdnewm|| @end|ng |rom dcn@d@v|@@c@@u@
Wed Jan 20 05:27:34 CET 2021

a) I recommend _not_ overwriting the input files. Very difficult to debug/recover if anything goes wrong.

b) I recommend making a function that takes the file name, source directory, and destination directory, and reads the file, makes the change, and writes it to the output directory.

c) Your life may be easier if you use readLines() and writeLines rather than a more sophisticated parsing function like read.table(). Adding a new string to a vector of strings is straightforward.

On January 19, 2021 3:45:53 PM PST, Miluji Sb <milujisb using gmail.com> wrote:
>Dear all,
>I have more than 200 text files in a folder without header - example
>I would like to read, add a common date header to all the files, and
>(replace) the files.
>## Read files
>filelist = list.files(pattern = ".*.txt")
>datalist = lapply(filelist, function(x)read.table(x, header=F))
>## What I want to add
>date <- 20000101
>datalist _new <- lapply(datalist, function(x) rbind(x, date))
>How do I add this date as a common header and replace the files? Any
>will be highly appreciated. Thank you.
>## Sample data
>xy <- dput(head(x,6))
>structure(list(V1 = c("-5.28082885742185,-0.509039307",
>"-2.07150878906248,6.264276123", "-1.11102905273435,6.365716553",
>"2.37749633789065,14.57106934", "4.9619079589844,18.91350708"
>)), row.names = c(NA, 6L), class = "data.frame")
>	[[alternative HTML version deleted]]
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Sent from my phone. Please excuse my brevity.

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