\name{column_order-Heatmap-method}
 \alias{column_order,Heatmap-method}
 \title{
 Get column order from a heatmap list
 }
 \description{
 Get column order from a heatmap list
 }
 \usage{
 \S4method{column_order}{Heatmap}(object)
 }
 \arguments{
 
   \item{object}{a \code{\link{Heatmap-class}} object}
 
 }
 \value{
 A vector containing column orders
 }

 \author{
 Zuguang Gu <z.gu@dkfz.de>
 }

 \examples{

 mat = matrix(rnorm(100), 10)
 ht = Heatmap(mat)
 column_order(ht)
 ht = Heatmap(mat, km = 2)
 column_order(ht)

 }