R/comp11.R

In BNPTSclust: A Bayesian Nonparametric Algorithm for Time Series Clustering

comp11 <-
function(y){
  
  # Function that computes the distinct observations in a numeric vector.
  # It is based entirely on the "comp1" function from the BNPdensidty 
  # package with the exception that it returns the variable that 
  # rearranges the numeric vector into one with its unique values only. 
  # 
  # IN:
  # 
  # y <- numeric vector. 
  # 
  # OUT: 
  # 
  # jstar <- variable that rearranges "y" into a vector with its unique
  #          values. 
  # nstar <- frequency of each distinct observation in "y". 
  # rstar <- number of distinct observations in "y".
  # gn    <- variable that indicates the group number to which every
  #          entry in "y" belongs. 
  
  n <- length(y)
  mat <- outer(y, y, "==")
  jstar <- led <- rep(FALSE, n)
  for (j in seq(n)) {
    if (!led[j]) {
      jstar[j] <- TRUE
      if (j == n) 
        break
      ji <- seq(j + 1, n)
      tt <- mat[ji, j] %in% TRUE
      led[ji] <- led[ji] | tt
    }
    if (all(led[-seq(j)])) 
      break
  }
  
  ystar <- y[jstar]
  nstar <- apply(as.matrix(mat[, jstar]), 2, sum)
  rstar <- length(nstar)
  gn <- match(y, ystar)
  
  return(list(jstar = jstar, nstar = nstar, rstar = rstar, gn = gn))
  
}