#' @name leading0
#' @keywords zero
#' @author Sven E. Templer \email{sven.templer@@gmail.com}
#' @title Numeric to Character with Leading Zero(s)
#' @description
#' Transform numeric values to character string prepending leading zero(s).
#' @param num Numeric vector (character also possible) to transform.
#' @param digits Numeric value of minimum length of output strings.
#' @return
#' Character vector with same length of strings of each value.
#' Original "string" is prepended by zero(s).
#' String length is at least \code{max(nchar(as.character(num)))}.
#' @examples
#' #
#'
#' # use with paste to generate strings of equal size:
#' paste0("observation", leading0(1:10, 3))
#'
#' #
#' @export leading0
leading0 <- function (num, digits = 2) {
m <- nchar(num)
digits <- max(digits, max(m))
zeros <- paste(rep(0, digits), collapse="")
paste0(substring(zeros, 0, digits - m), num)
}
# Many thanks to Bill Venables for the improved version.
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.