R/getAverageOfTimeSeries.R

In neuroconductor-devel/ANTsR: ANTs in R: Quantification Tools for Biomedical Images

#' @title getAverageOfTimeSeries
#' @description  Returns a 3D average of a 4D time series.
#' @usage getAverageOfTimeSeries(img)
#' @param img input 4D image
#' @return 3D ants image is output
#' @author Avants BB
#' @examples
#' img<-as.antsImage( array(data = rep(0,10^4), dim = c(10,10,10,10) ) )
#' avg<-getAverageOfTimeSeries( img )
#' @export getAverageOfTimeSeries
getAverageOfTimeSeries <- function(img) {
  if (nargs() == 0) {
    return(1)
  }
  myilist = splitNDImageToList( img )
  averageImage = myilist[[ 1 ]]
  for ( i in 2:length( myilist ) )
    averageImage = averageImage + myilist[[ i ]]
  return( averageImage / length( myilist ) )
}