#' @details
#'
#' The windowing constraint uses a centered window. The calculations expect a value in
#' \code{window.size} that represents the distance between the point considered and one of the edges
#' of the window. Therefore, if, for example, \code{window.size = 10}, the warping for an
#' observation \eqn{x_i} considers the points between \eqn{x_{i-10}} and \eqn{x_{i+10}}, resulting
#' in \code{10(2) + 1 = 21} observations falling within the window.
#'