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\name{Import}
\alias{Import}
\title{
Import data from many file formats
}
\description{
Uses the \code{import} function from the \pkg{rio} package to read a data.frame from a variety of file types. The \code{Import} function includes 2 additional arguments adding row names and for converting character and logical variables to factors for some file types.}
\usage{
Import(file, format, ..., row.names=TRUE,
stringsAsFactors = FALSE)
}
\arguments{
\item{file}{
A character string naming a file, URL, or .zip or .tar archive. See the details below. If the file name has an extension like \code{.xlsx} or \code{.csv} then the type of file is inferred from the extension.
}
\item{format}{
If an extension is not present in the file name or it is wrong, the file format can be set with this argument; see \code{\link[rio]{import}}.
}
\item{\dots}{
Additional arguments passed to \code{\link[rio]{import}}.
}
\item{row.names}{
If \code{TRUE}, the default, the left-most character variable that has all unique elements is removed from the data frame and set to be \code{row.names}. To match \code{import}, set \code{row.names=FALSE}.
}
\item{stringsAsFactors}{
If \code{TRUE}, then character variables that do not have all unique elements are converted to factors. The default is \code{FALSE}. Prior to May 2020 the default was determined by \code{getOption("stringsAsFactors")}, which then defaulted to \code{TRUE}. This option is \code{FALSE} in R 4.0.0 and has been deprecated.}
}
\details{
This function calls the \code{\link[rio]{import}} function to read a data frame from a file. Many file types are supported. For files of type \code{"txt", "csv", "xlsx", "xls"} or \code{ "ods"} the arguments \code{row.names} and \code{stringsAsFactors} can be used to add row names and convert character variables to factors, respectively. Many more details are given on the man page for \code{import}.
}
\value{
A data frame. See \code{\link[rio]{import}} for more details
}
\author{Sanford Weisberg \email{sandy@umn.edu}}
\seealso{
\code{\link[rio]{import}}, \code{\link{Export}}, \code{\link{strings2factors}}
}
\examples{
if(require("rio")) {
head(Duncan, 3) # first three rows
Export(Duncan, "Duncan.csv", keep.row.names="occupation")
Duncan2 <- Import("Duncan.csv") # Automatically restores row.names and factors
brief(Duncan2)
identical(Duncan, Duncan2) # FALSE because type is of a different class
Duncan3 <- Import("Duncan.csv", stringsAsFactors=TRUE)
brief(Duncan3)
identical(Duncan, Duncan3) # TRUE type is of same class
# cleanup
unlink("Duncan.csv")
}
}
\keyword{ utilities }
\keyword{ connections }
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