| % File src/library/utils/man/count.fields.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2018 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{count.fields} |
| \title{Count the Number of Fields per Line} |
| \usage{ |
| count.fields(file, sep = "", quote = "\"'", skip = 0, |
| blank.lines.skip = TRUE, comment.char = "#") |
| } |
| \alias{count.fields} |
| \arguments{ |
| \item{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{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{quote}{the set of quoting characters} |
| |
| \item{skip}{the number of lines of the data file to skip before |
| beginning to read data.} |
| |
| \item{blank.lines.skip}{logical: if \code{TRUE} blank lines in the |
| input are ignored.} |
| |
| \item{comment.char}{character: a character vector of length one |
| containing a single character or an empty string.} |
| } |
| \description{ |
| \code{count.fields} counts the number of fields, as separated by |
| \code{sep}, in each of the lines of \code{file} read. |
| } |
| \details{ |
| 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}}. |
| |
| Consistent with \code{\link{scan}}, \code{count.fields} allows |
| quoted strings to contain newline characters. In such a case the |
| starting line will have the field count recorded as \code{NA}, and |
| the ending line will include the count of all fields from the |
| beginning of the record. |
| |
| } |
| \value{ |
| A vector with the numbers of fields found. |
| } |
| \seealso{ |
| \code{\link{read.table}} |
| } |
| \examples{ |
| fil <- tempfile() |
| cat("NAME", "1:John", "2:Paul", file = fil, sep = "\n") |
| count.fields(fil, sep = ":") |
| unlink(fil) |
| } |
| \keyword{file} |