\name{import_env_file}
\alias{import_env_file}
\title{Read a UniFrac-formatted ENV file.}
\usage{
  import_env_file(envfilename, tree=NULL, sep="\t", ...)
}
\arguments{
  \item{envfilename}{(Required). A charater string of the
  ENV filename (relative or absolute)}

  \item{tree}{(Optional). \code{\link{phylo-class}} object
  to be paired with the output otuTable.}

  \item{sep}{A character string indicating the delimiter
  used in the file. The default is \code{"\t"}.}

  \item{...}{Additional parameters passed on to
  \code{\link{read.table}}.}
}
\value{
  An \code{\link{otuTable-class}}, or
  \code{\link{phyloseq-class}} if a
  \code{\link{phylo-class}} argument is provided to
  \code{tree}.
}
\description{
  Convenience wrapper function to read the
  environment-file, as formatted for input to the UniFrac
  server (\url{http://bmf2.colorado.edu/unifrac/}). The
  official format of these files is that each row specifies
  (in order) the sequence name, source sample, and
  (optionally) the number of times the sequence was
  observed.
}
\examples{
# import_env_file(myEnvFile, myTree)
}
\references{
  \url{http://bmf2.colorado.edu/unifrac/}
}
\seealso{
  \code{\link{import}}, \code{\link{tipglom}}
}