R/extract_link.R

In ahorawzy/HVS: This package is designed for Highway Virtual Traffic Survey Station project.

#' Extract links from a path string.
#'
#' \code{extract_link} can extracts links information from a path string.
#'
#' @param path_i A string contains path information and seperated by ','
#' @return A character vector contains all links in this path.
#' @examples
#' extract_link('1,3,5,6,7,10')
#'
#' @export
#'
extract_link <- function(path_i) {
    p <- path_i
    p <- strsplit(p, split = ",")[[1]]
    Nlink <- length(p) - 1
    result <- numeric(length = Nlink)
    for (i in 1:Nlink) {
        result[i] <- paste(p[i:(i + 1)], collapse = "-")
    }
    return(result)
}