R/ebpmf_util.R

In stephenslab/ebpmf:

#' @export init_ebpmf
init_ebpmf <- function(X,K, init, d){
  qg = init$qg
  if(is.null(qg)){
    qg = initialize_qg(X, K, init_method =  init$init_method, init_iter = init$init_iter)
  }
  ## TODO: speedup
  ## compute `a`
  a = replicate(length(d$x), 0)
  for(k in 1:K){
    b_k_tmp <- qg$qls_mean_log[d$i, k] + qg$qfs_mean_log[d$j, k]
    a <- pmax(a, b_k_tmp)
  }
  ## compute b
  b = qg$qls_mean_log[d$i, 1] + qg$qfs_mean_log[d$j, 1] - a
  for(k in 2:K){
    b_k = qg$qls_mean_log[d$i, k] + qg$qfs_mean_log[d$j, k] - a
    b <- log( exp(b) + exp(b_k)  )
  }
	return(list(qg = qg, b = b, a = a))
}