\name{data.frame2GRanges}
 \alias{data.frame2GRanges}
 \title{
   Converts a data frame to a GRanges.
 }
 \description{
   Converting a data.frame to a GRanges object.  The data.frame needs
   columns like chr, start and end (strand is optional).  Additional
   columns may be kept in the GRanges object.
 }
 \usage{
 data.frame2GRanges(df, keepColumns = FALSE, ignoreStrand = FALSE)
 }
 \arguments{
   \item{df}{A \code{data.frame} with columns \code{chr} or
     \code{seqnames}, \code{start}, \code{end} and optionally a
     \code{strand column}.}    
   \item{keepColumns}{In case \code{df} has additional columns, should

     these columns be stored as metadata columns on the return GRanges
     or should they be discarded.}

   \item{ignoreStrand}{In case \code{df} has a \code{strand} column,
     should this column be ignored.}
 }
 \note{
   In case \code{df} has \code{rownames}, they will be used as
   \code{names} for the return object.
 }
 \value{

   An object of class \code{GRanges}

 }
 \author{
   Kasper Daniel Hansen \email{khansen@jhsph.edu}
 }
 \examples{
 df <- data.frame(chr = "chr1", start = 1:3, end = 2:4,
                  strand = c("+","-","+"))
 data.frame2GRanges(df, ignoreStrand = TRUE)
 }