Thanks Jim. I tried:
A<-read.table(file="243_47mel_withnormal_expression_log2.txt", +header=TRUE,row.names=1,colClasses=c('factor', rep('numeric',486))) by specifying colClass but it did not work. The error message I got is: > A<-read.table(file="243_47mel_withnormal_expression_log2.txt",header=TRUE,row.names=1,colClasses=c('factor', > rep('numeric',486))) Error in scan(file, what, nmax, sep, dec, quote, skip, nlines, na.strings, : scan() expected 'a real', got 'B' Let me try what you suggested. Thanks! Allen On Nov 10, 2007 12:07 AM, jim holtman <[EMAIL PROTECTED]> wrote: > If they are all numeric, then read it in with: > > x <- scan('yourfile', what=0) # assuming blank separators > > This will create a single vector of the values. Now this comes in in > row order if that is what your data file has, so you could just add > dimensions of > > dim(x) <- c(487, 238305) > > rows and columns are transposed, but if you have enough memory, you > can transpose them, or just leave the data as is, and change your > processing to reorder the rows/cols. This should lets you read it in > in the fastest manner and then play with it. > > > On Nov 9, 2007 11:52 PM, affy snp <[EMAIL PROTECTED]> wrote: > > Hi Jim, > > > > Thanks a lot! I am currently running it on my laptop but without any > > success. I could upload it to a server which is with 8Gb memory > > and it might be better to go from there. > > > > Actually, I could have the whole file splitted in two parts, > > one with 2nd column to 95th column, the other one with > > the rest of columns. However, I need all rows for the > > two parts. > > > > The file is in txt format and around 480Mb, very large though. > > Yes, it is of numeric values. > > > > I appreciate! > > > > Allen > > > > > > > > > > > > > > On Nov 9, 2007 11:46 PM, jim holtman <[EMAIL PROTECTED]> wrote: > > > If they are all numeric, you can use 'scan' to read them in. With > > > that amount of data, you will need almost 1GB to contain the single > > > object. If you want to do any processing, you will probably need a > > > machine with at least 3-4GB of physical memory, preferrably a 64-bit > > > version of R. What type of computer are you using? Do you really > > > need all the data in at once, or can you process it in smaller batches > > > (e.g., 20,000 rows at a time)? So a little more detail on what you > > > actually want to do with the data would be useful, since it does > > > create a very large object. BTW how large is the file you are reading > > > and what is its format? Have you considered a database with this > > > amount of data? > > > > > > > > > On Nov 9, 2007 11:39 PM, affy snp <[EMAIL PROTECTED]> wrote: > > > > Dear list, > > > > > > > > I need to read in a big table with 487 columns and 238,305 rows (row > > > > names > > > > and column names are supplied). Is there a code to read in the table in > > > > a fast way? I tried the read.table() but it seems that it takes forever > > > > :( > > > > > > > > Thanks a lot! > > > > > > > > Best, > > > > Allen > > > > > > > > ______________________________________________ > > > > 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. > > > > > > > > > > > > > > > > -- > > > Jim Holtman > > > Cincinnati, OH > > > +1 513 646 9390 > > > > > > What is the problem you are trying to solve? > > > > > > > > > -- > > Jim Holtman > Cincinnati, OH > +1 513 646 9390 > > What is the problem you are trying to solve? > ______________________________________________ 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.