\Header{count.fields}{Count the Number of Fields per Line}
\keyword{file}{count.fields}
\begin{Description}\relax
\code{count.fields} counts the number of fields, as separated by
\code{sep}, in each of the lines of \code{file} read.
\end{Description}
\begin{Usage}
\begin{verbatim}
count.fields(file, sep = "", quote = "\"'", skip = 0,
             blank.lines.skip = TRUE, comment.char = "#")
\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\code{file}] a character string naming an ASCII data file, or a
\code{\Link{connection}}, which will be opened if necessary,
and if so closed at the end of the function call.
\item[\code{sep}] the field separator character.  Values on each line of the
file are separated by this character.  By default, arbitrary amounts
of whitespace can separate fields.
\item[\code{quote}] the set of quoting characters
\item[\code{skip}] the number of lines of the data file to skip before
beginning to read data.
\item[\code{blank.lines.skip}] logical: if \code{TRUE} blank lines in the
input are ignored.
\item[\code{comment.char}] character: a character vector of length one
containing a single character or an empty string.
\end{ldescription}
\end{Arguments}
\begin{Details}\relax
This used to be used by \code{\Link{read.table}} and can still be
useful in discovering problems in reading a file by that function.

For the handling of comments, see \code{\Link{scan}}.
\end{Details}
\begin{Value}
A vector with the numbers of fields found.
\end{Value}
\begin{SeeAlso}\relax
\code{\Link{read.table}}
\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
cat("NAME", "1:John", "2:Paul", file = "foo", sep = "\n")
count.fields("foo", sep = ":")
unlink("foo")
\end{ExampleCode}
\end{Examples}

