?try df <- try(read.table(...)) if (inherits(df, 'try-error')){ what to do if file empty }
On Fri, Jan 1, 2010 at 3:55 PM, Ted Harding <ted.hard...@manchester.ac.uk>wrote: > On 01-Jan-10 20:41:52, Peng Yu wrote: > > read.table terminates the program if the input file is empty. Is there > > way to let the program continue and return me a NULL instead of > > terminating the program? > > > > $ Rscript read_empty.R > >> read.table("empty_data.txt") > > Error in read.table("empty_data.txt") : no lines available in input > > Execution halted > > $ cat read_empty.R > > read.table("empty_data.txt") > > $ cat empty_data.txt; echo EOF > > EOF > > If I understand the point of your query correctly, the following, > from "?read.table", would be relevant: > > Value: > A data frame (?data.frame?) containing a representation of the > data in the file. > > Empty input is an error unless "col.names" is specified, when a > 0-row data frame is returned: similarly giving just a header line > if "header = TRUE" results in a 0-row data frame. Note that in > either case the columns will logical unless ?colClasses? was > supplied. > > The result would not be NULL, but can be tested for zero rows. > > Hoping this helps, > Ted. > > -------------------------------------------------------------------- > E-Mail: (Ted Harding) <ted.hard...@manchester.ac.uk> > Fax-to-email: +44 (0)870 094 0861 > Date: 01-Jan-10 Time: 20:55:35 > ------------------------------ XFMail ------------------------------ > > ______________________________________________ > 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<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 that you are trying to solve? [[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.