R/findfactors.r

In htc502/ewrefxn: this package collects r fxns useful in my daily coding life

#' prime decomposition
#'
#' This fxn decomposite a number into primes
#' 
#' @param n number to decomposite
#' @author credit to https://rosettacode.org/wiki/Prime_decomposition#R
#' @keywords prime decomposition
#' @examples
#' 
#' @rdname findfactors
#' @export


findfactors <- function(n) {
  a <- NULL
  if (n > 1) {
    while (n %% 2 == 0) {
      a <- c(a, 2)
      n <- n %/% 2
    }
    k <- 3
    while (k * k <= n) {
      while (n %% k == 0) {
        a <- c(a, k)
        n <- n %/% k
      }
      k <- k + 2
    }
    if (n > 1) a <- c(a, n)
  }
  a
}