R/numeric-features.R

In dannymorris/colstats: Column-wise statistics for data frames

get_shapiro_wilk_pvalue <- function(x) {
  shapiro.test(x)$p.value %>%
    round(., 3)
}

kurtosis <- function(x, type) {

  if (any(ina <- is.na(x))) {
    if (na.rm)
      x <- x[!ina]
    else return(NA)
  }
  if (!(type %in% (1:3)))
    stop("Invalid 'type' argument.")
  n <- length(x)
  x <- x - mean(x)
  r <- n * sum(x^4)/(sum(x^2)^2)
  y <- if (type == 1)
    r - 3
  else if (type == 2) {
    if (n < 4)
      stop("Need at least 4 complete observations.")
    ((n + 1) * (r - 3) + 6) * (n - 1)/((n - 2) * (n - 3))
  }
  else r * (1 - 1/n)^2 - 3
  y
}