The problem is the commas, not the quotes: > Lines.raw <- '"1,001.23""1,008,000.456"' > Lines <- readLines(textConnection(Lines.raw)) > Lines <- gsub(",", "", Lines) > read.table(textConnection(Lines)) V1 V2 1 1001.23 1008000
On Wed, Aug 20, 2008 at 2:27 PM, Aval Sarri <[EMAIL PROTECTED]> wrote: > Hello; > > I am new user of R; so pardon me. > > I am reading a .txt file that has around 50+ numeric columns with '\t' > as separator. I am using read.csv function along with colClasses but > that fails to recognize double quoted numeric values. (My numeric > values are something like "1,001.23"; "1,008,000.456".) Basically > read.csv fails with - "scan() expected 'a real', got '"1,044.059"'. > > What I have tried and problems with them: > > > 1) I tried scan and pipe but getting following error message; that is > how do I replace all double quotes with nothing. I tired enclosing sed > command in single quotes but that does not help. > (Though the sed command works from shell) > > scan(pipe("sed -e s/\"//g DataAll.txt"), sep="\t") > sh: Syntax error: Unterminated quoted string > > 2) On mailing list on solution I found was setAs() described here > http://www.nabble.com/Re%3A--R--read.table()-and-scientific-notation-p6734890.html > > 3) Other than using as.is=TRUE and then doing as.numeric for numeric > columns what is the solution? But then how do I efficiently convert > 50+ columns to numeric using regular expression? That is all my > numeric columns name starts with 'X' character, so how do I use sapply > and/or regular expression to convert all columns starting with X to > numeric? What is the alternate method to do so? > > Basically 2 and 3 works but which one is efficient and correct way to do this. > > (Also what is most efficient way to apply field level validation and > conversion while reading a file? Does one has to read the file and > only after that validation and conversion can happen?) > > Thanks for taking out time to read through the mail. > > Thanks and Regards > -Aval > > ______________________________________________ > 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. > ______________________________________________ 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.