David, Using the ?count.fields revealed that I only have 2410 columns. That fixed the problem I had. I used, data_tmp[,842:2410] and that gave me the solution I was looking for. This, ironically, also solved the other problem I had.
As for: > > You also say file.remove( fileout) , then you try to append to fileout. > Does that make sense? > > I am dealing with a file that is about 4GB in size. It has over 500,000 lines. As I process it, I am grabbing a chunk of lines, filtering the unwanted columns, and writing that chunk to the file. I suppose I should have two write functions, one that does not append (the first write), and the rest that append. Thank you very much, to all of you who helped. I can write good C code, but the 'R' is all new to me :) -- Jason Thibodeau [[alternative HTML version deleted]] ______________________________________________ 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.