R/rtAgeing.r

In AndySouth/rtsetse: simulating tsetse fly populations

#' ageing of adults or pupae in a single population
#' 
#' \code{rtAgeing} simply advances the age of all classes in the passed vector.  
#' Note this isn't called by \code{\link{rtAgeingGrid}} which is used for grid models.

#' @param v a vector of age distribution 
#' @param label a string describing what is being passed, added to any warning messages 
#' 
#' @return an updated vector
#' @export

rtAgeing <- function( v, label )
{
  
  #set all numbers in [age] to those from [age-1]
  
  #!if there are any in the max age class they will be lost here
  #!add a warning to that effect
  #!disabled for now because it slows down shiny apps
  #!bring it back at some stage
  #if ( v[length(v)] != 0 )
  #  message("in rtAgeing members of final age class will be lost :",v[length(v)]," ",label)
    #warning()
  
  #go down through ages to avoid double counting
#   for( age in length(v):2 )  {
#     v[age] <- v[age-1]    
#   }
#   #set age 1 to 0 to avoid potential bugs
#   v[1] <- 0
  
  #how to do this in a vectorised way
  #can just use c() & stick a zero on the start
  #v2 <- c(0,v[-length(v)])
  v <- c(0,v[-length(v)])
  
  #returning updated vector
  invisible( v )
  
}