Hi guys; I want to write some text at the first line of an output file. The output file will be used for other software. In particular, the following text "ampl.tab 2 1" needs to be added to the first line of an df output file. As a hypothetic example, the output in text file should be like: ampl.tab 2 1 A B 2 3 4 6 2 0 Thanks for help. Yihsu [[alternative HTML version deleted]]
Hi. You can't. But using a second file where you first write your header and then append the original file is a solution. ?cat and ?write.table with a focus on the 'append' argument should help. you can then use ?unlink to delete the original file and ?file.rename to rename the second, if desired. Best, Sven. On 22 October 2014 02:32, YIHSU CHEN <yihsuc at gmail.com> wrote:> Hi guys; > > I want to write some text at the first line of an output file. The output > file will be used for other software. In particular, the following text > "ampl.tab 2 1" needs to be added to the first line of an df output file. > As a hypothetic example, the output in text file should be like: > > ampl.tab 2 1 > A B > 2 3 > 4 6 > 2 0 > > Thanks for help. > > Yihsu > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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.
Hello, Just use ?cat and ?write.table with append = TRUE. Something like the following. txt <- "ampl.tab 2 1" dat <- read.table(text = " A B 2 3 4 6 2 0 ", header = TRUE) tmp <- "tmp.txt" cat(txt, "\n", file = tmp) " Don't forget the newline "\n" write.table(dat, file = tmp, append = TRUE, row.names = FALSE) #unlink(tmp) # Clean up Hope this helps, Rui Barradas Em 22-10-2014 01:32, YIHSU CHEN escreveu:> Hi guys; > > I want to write some text at the first line of an output file. The output > file will be used for other software. In particular, the following text > "ampl.tab 2 1" needs to be added to the first line of an df output file. > As a hypothetic example, the output in text file should be like: > > ampl.tab 2 1 > A B > 2 3 > 4 6 > 2 0 > > Thanks for help. > > Yihsu > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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. >