AMR/R/kurtosis.R

62 lines
2.6 KiB
R
Executable File

# ==================================================================== #
# TITLE #
# Antimicrobial Resistance (AMR) Analysis #
# #
# SOURCE #
# https://gitlab.com/msberends/AMR #
# #
# LICENCE #
# (c) 2018-2020 Berends MS, Luz CF et al. #
# #
# This R package is free software; you can freely use and distribute #
# it for both personal and commercial purposes under the terms of the #
# GNU General Public License version 2.0 (GNU GPL-2), as published by #
# the Free Software Foundation. #
# #
# We created this package for both routine data analysis and academic #
# research and it was publicly released in the hope that it will be #
# useful, but it comes WITHOUT ANY WARRANTY OR LIABILITY. #
# Visit our website for more info: https://msberends.gitlab.io/AMR. #
# ==================================================================== #
#' Kurtosis of the sample
#'
#' @description Kurtosis is a measure of the "tailedness" of the probability distribution of a real-valued random variable.
#' @inheritSection lifecycle Questioning lifecycle
#' @param x a vector of values, a [`matrix`] or a [`data.frame`]
#' @param na.rm a logical value indicating whether `NA` values should be stripped before the computation proceeds.
#' @seealso [skewness()]
#' @rdname kurtosis
#' @inheritSection AMR Read more on our website!
#' @export
kurtosis <- function(x, na.rm = FALSE) {
UseMethod("kurtosis")
}
#' @method kurtosis default
#' @rdname kurtosis
#' @export
kurtosis.default <- function(x, na.rm = FALSE) {
x <- as.vector(x)
if (na.rm == TRUE) {
x <- x[!is.na(x)]
}
n <- length(x)
n * base::sum((x - base::mean(x, na.rm = na.rm))^4, na.rm = na.rm) /
(base::sum((x - base::mean(x, na.rm = na.rm))^2, na.rm = na.rm)^2)
}
#' @method kurtosis matrix
#' @rdname kurtosis
#' @export
kurtosis.matrix <- function(x, na.rm = FALSE) {
base::apply(x, 2, kurtosis.default, na.rm = na.rm)
}
#' @method kurtosis data.frame
#' @rdname kurtosis
#' @export
kurtosis.data.frame <- function(x, na.rm = FALSE) {
base::sapply(x, kurtosis.default, na.rm = na.rm)
}