R/Skmeans.R

In nikrodis/SAA: kmeans and dbscan

#' @name skmeans
#' @return
#' @export
skmeans <- function(x, k) {
  bin <- data.frame(scale(x))
  centroid <- dplyr::sample_n(bin, k)
  centr_clstr <- centroid
  repeat {
    dis <-
      data.frame(apply(
        centroid,
        1,
        FUN = function(x) {
          apply(
            bin,
            1,
            FUN = function(y) {
              sqrt(sum((y - x) ^ 2))
            }
          )
        }
      ))
    clstr <- apply(
      dis,
      1,
      FUN = function(x) {
        which.min(x)
      }
    )
    for (ki in 1:k) {
      for (j in seq_len(ncol(bin))) {
        centr_clstr[ki, j] <-  mean(as.matrix(bin[clstr == ki, ][, j]))
      }
    }
    if (sum(centroid != centr_clstr) == 0) {
      break
    } else {
      centroid <- centr_clstr
    }
  }
  return(cbind(x, "clstr" = factor(clstr)))
}