R/rDirichDraw.R

In WarrRich/LCMBounds: Confidence Intervals for a Linear Combination of Multinomial Probabilities

#'  Function to draw 'random' probability vectors fixed at a particular L
#'
#' @param mass Not sure Yet.
#' @param L Not sure Yet.
#' @param bag Not sure Yet.
#' 
#' @importFrom stats rgamma

rDirichDraw <- function(mass,L,bag) {
  # mass is a scalar, L is a scalar
  gammas <- bag$weights
  for (i in 1:length(bag$weights)) {
    gammas[[i]] <- rgamma(bag$weights.lengths[i],bag$mass[[i]],1)
    gammas[[i]] <- gammas[[i]]+bag$mass[[i]]*(gammas[[i]]==0)
  }
  adjustment <- uniroot(objective.funct,c(0,1),L=L,gammas=gammas,bag=bag,tol=1e-13)$root
  adjusted.weights(adjustment,gammas,bag)
}