Thanks again, David I think that this could work. Final questions: 1. I have read that read.fwt could be slow for big tables (my tables have aprox. 160000 records, with 176 characters of recordlenght, almost 28MBytes). Could that be a problem? 2. If using read.fwt is not a problem, wouldn't be better to read all the records by read.fwt into a dataframe with the Type 1 structure, and then process the Type 2 records in the dataframe adding new fields for these records (NULL valued for Type 1)? Hug
--- On Mon, 2/1/10, David Winsemius <dwinsem...@comcast.net> wrote: > From: David Winsemius <dwinsem...@comcast.net> > Subject: Re: [R] Import fixed-format ascii file with mixed record types > To: "trece por ciento" <el13porcie...@yahoo.com> > Cc: r-help@r-project.org > Date: Monday, February 1, 2010, 2:23 PM > > On Feb 1, 2010, at 2:33 PM, trece por ciento wrote: > > > Thanks David, but can read.fwf cope with different > record types? > > For example, if recordtype is the 4th character, I > could have: > > > > 011125678 ---> This is record Type 1 > > 011136779 ---> This is record Type 1 > > 011124943 ---> This is record Type 1 > > 011286711 ---> This is record Type 2 > > 011234872 ---> This is record Type 2 > > 011135628 ---> This is record Type 1 > > > > So, how can I tell read.fwf to take the correct type > into account? > > You may need to separate the line-types first. If the > numbers of lines are not too large then this would exemplify > a strategy: > > > txt <- "011125678 > + 011136779 > + 011124943 > + 011286711 > + 011234872 > + 011135628" > > > substr(readLines(textConnection(txt)), 4,4) > [1] "1" "1" "1" "2" "2" "1" > > file1 <- > readLines(textConnection(txt))[substr(readLines(textConnection(txt)), > 4,4) == "1"] > > file2 <- > readLines(textConnection(txt))[substr(readLines(textConnection(txt)), > 4,4) == "2"] > > file1 > [1] "011125678" "011136779" "011124943" "011135628" > > file2 > [1] "011286711" "011234872" > > Then these text objects could be processed with > read.fwf(textConnection(file1) and the same for file2. > > --David. > > > Thanks again, > > Hug > > > > --- On Mon, 2/1/10, David Winsemius <dwinsem...@comcast.net> > wrote: > > > > From: David Winsemius <dwinsem...@comcast.net> > > Subject: Re: [R] Import fixed-format ascii file with > mixed record types > > To: "trece por ciento" <el13porcie...@yahoo.com> > > Cc: r-help@r-project.org > > Date: Monday, February 1, 2010, 12:01 PM > > > > > > On Feb 1, 2010, at 11:40 AM, trece por ciento wrote: > > > >> I need to import several ascii files in fixed > format with two different record types. The data comes from > European Labor Force Surveys, wich is a household survey. > The first record type is for people over 16 years, and the > second much sorter is for people aged 15 or less (this > record has a filler with several blanks to get the same > record length). > >> The files tipically have 160000 records, with 176 > characters per record, the data is numeric, corresponding to > 102 variables, mostly integers (seven variables have two > decimals). My opertating system is Windows XP. > >> My questions: > >> 1. Wich do you think is the best way to import the > files into R? > > > > > > ?read.fwf > > > >> 2. Could you give me any references or examples? > > > > There are examples in the help page. > > > >> Thanking you in advance, > >> Hug > >> > >> > >> > >> > >> [[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. > > > > David Winsemius, MD > > Heritage Laboratories > > West Hartford, CT > > > > > > > > > > > > David Winsemius, MD > Heritage Laboratories > West Hartford, CT > > ______________________________________________ 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.
