What types of data are in each file? All numbers, or a mix of numbers and characters? Any missing data or special NA values?
On Wed, May 13, 2009 at 7:45 AM, SYKES, Jennifer <jennifer.sy...@nats.co.uk> wrote: > Hello > > > > Apologies if this is a simple question, I have searched the help and > have not managed to work out a solution. > > Does anybody know an efficient method for reading many text files of the > same format into one table/dataframe? > > > > I have around 90 files that contain continuous data over 3 months but > that are split into individual days data and I need the whole 3 months > in one file for analysis. Each days file contains a large amount of > data (approx 30MB each) and so I need a memory efficient method to merge > all of the files into the one dataframe object. From what I have read I > will probably want to avoid using for loops etc? All files are in the > same directory, none have a header row, and each contain around 180,000 > rows and the same 25 columns/variables. Any suggested packages/routines > would be very useful. > > > > Thanks > > > > Jennifer > > > > > > > > ----------------------------------------- > *******************************************************************If > you are not the intended recipient, please notify our Help Desk at > Email postmas...@nats.co.uk immediately. You should not copy or use > this email or attachment(s) for any purpose nor disclose their > contents to any other person. NATS computer systems may be > monitored and communications carried on them recorded, to secure > the effective operation of the system and for other lawful > purposes. Please note that neither NATS nor the sender accepts any > responsibility for viruses or any losses caused as a result of > viruses and it is your responsibility to scan or otherwise check > this email and any attachments. NATS means NATS (En Route) plc > (company number: 4129273), NATS (Services) Ltd (company number > 4129270), NATSNAV Ltd (company number: 4164590) or NATS Ltd > (company number 3155567) or NATS Holdings Ltd (company number > 4138218). All companies are registered in England and their > registered office is at 5th Floor, Brettenham House South, > Lancaster Place, London, WC2E 7EN. > ********************************************************************** > > [[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. > -- Mike Lawrence Graduate Student Department of Psychology Dalhousie University Looking to arrange a meeting? Check my public calendar: http://tr.im/mikes_public_calendar ~ Certainty is folly... I think. ~ ______________________________________________ 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.