Thank you Dr. Ripley and Christoph Buser for your explanations and help. Using sep = " " within scan worked within lines of my file, but then I gained an NA record when wrapping from one line to the next (because the linebreak character is no longer recognized as a sep?). So, I'll continue by ensuring each group I read ends at the end of a line (as scan was designed), and by using scan without the sep option.
FYI, Here's how the NA showed up, each line is 800 numbers long: >test4 <- scan(cn.test, n=1600, sep = " ") >test5 <- scan(cn.test, n=1600) >test4[797:803] [1] 81.00000 81.08746 81.89484 82.00000 NA 580.09030 576.90300 > test5[797:803] [1] 81.01944 81.62060 81.96495 82.00000 82.00000 567.91840 563.10470 Thanks again. Tim >>> Prof Brian Ripley <[EMAIL PROTECTED]> 01/19/05 03:42AM >>> This is because scan() has a private pushback. Either: 1) Read the file a whole line at a time: I cannot see why you need to do so here nor in your sketched application. or 2) Use an explicit separator, e.g. " " in your example. scan() is not designed to read parts of lines of a file, On Tue, 18 Jan 2005, Tim Howard wrote: > R gurus, > > My use of scan() seems to be dropping the first digit of sequential > scans on a connection. It looks like it happens only within a line: > >> cat("TITLE extra line", "235 335 535 735", "115 135 175", > file="ex.data", sep="\n") >> cn.x <- file("ex.data", open="r") >> a <- scan(cn.x, skip=1, n=2) > Read 2 items >> a > [1] 235 335 >> b <- scan(cn.x, n=2) > Read 2 items >> b > [1] 35 735 >> c <- scan(cn.x, n=2) > Read 2 items >> c > [1] 115 135 >> d <- scan(cn.x, n=1) > Read 1 items >> d > [1] 75 >> > > Note in b, I should get 535, not 35 as the first value. In d, I should > get 175. Does anyone know how to get these digits? > > The reason I'm not scanning the entire file at once is that my real > dataset is much larger than a Gig and I'll need to pull only portions of > the file in at once. I got readLines to work, but then I have to figure > out how to convert each entire line into a data.frame. Scan seems a lot > cleaner, with the exception of the funny character dropping issue. > > Thanks so much! > Tim Howard > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html