The R Project SVN R

Rev

Rev 59039 | Rev 74519 | Go to most recent revision | Details | Compare with Previous | Last modification | View Log | RSS feed

Rev Author Line No. Line
42333 ripley 1 
% File src/library/utils/man/count.fields.Rd
2 
% Part of the R package, http://www.R-project.org
62511 murdoch 3 
% Copyright 1995-2013 R Core Team
42333 ripley 4 
% Distributed under GPL 2 or later
5 
 
49 hornik 6 
\name{count.fields}
7 
\title{Count the Number of Fields per Line}
8 
\usage{
11287 ripley 9 
count.fields(file, sep = "", quote = "\"'", skip = 0,
16016 ripley 10 
             blank.lines.skip = TRUE, comment.char = "#")
49 hornik 11 
}
56186 murdoch 12 
\alias{count.fields}
49 hornik 13 
\arguments{
13932 ripley 14 
  \item{file}{a character string naming an ASCII data file, or a
15 
    \code{\link{connection}}, which will be opened if necessary,
16 
    and if so closed at the end of the function call.}
11287 ripley 17 
 
49 hornik 18 
  \item{sep}{the field separator character.  Values on each line of the
19 
    file are separated by this character.  By default, arbitrary amounts
6994 pd 20 
    of whitespace can separate fields.}
11287 ripley 21 
 
7895 pd 22 
  \item{quote}{the set of quoting characters}
11287 ripley 23 
 
49 hornik 24 
  \item{skip}{the number of lines of the data file to skip before
25 
    beginning to read data.}
11287 ripley 26 
 
27 
  \item{blank.lines.skip}{logical: if \code{TRUE} blank lines in the
28 
    input are ignored.}
16016 ripley 29 
 
30 
  \item{comment.char}{character: a character vector of length one
31 
    containing a single character or an empty string.}
49 hornik 32 
}
33 
\description{
6994 pd 34 
  \code{count.fields} counts the number of fields, as separated by
13932 ripley 35 
  \code{sep}, in each of the lines of \code{file} read.
49 hornik 36 
}
13932 ripley 37 
\details{
38 
  This used to be used by \code{\link{read.table}} and can still be
39 
  useful in discovering problems in reading a file by that function.
16016 ripley 40 
 
41 
  For the handling of comments, see \code{\link{scan}}.
62511 murdoch 42 
 
43 
  Consistent with \code{\link{scan}}, \code{count.fields} allows
44 
  quoted strings to contain newline characters.  In such a case the
45 
  starting line will have the field count recorded as \code{NA}, and
46 
  the ending line will include the count of all fields from the
47 
  beginning of the record.
48 
 
13932 ripley 49 
}
49 hornik 50 
\value{
51 
  A vector with the numbers of fields found.
52 
}
53 
\seealso{
54 
  \code{\link{read.table}}
55 
}
56 
\examples{
57 
cat("NAME", "1:John", "2:Paul", file = "foo", sep = "\n")
58 
count.fields("foo", sep = ":")
8098 ripley 59 
unlink("foo")
49 hornik 60 
}
286 maechler 61 
\keyword{file}