R/is_duplicated.R

In stackcon/rngt: General data science and utilities package

#' List duplicate values
#'
#' @param vect vector
#' @param na.rm exclude NA values
#' @param ... additional arguments passed to `base::duplicated`
#'
#' @return a logical vector the same length as `vect` indicating duplicated values
#' @export
#'
#' @examples
#' is_duplicated( c(1:10, 1:5) )
#' is_duplicated( c(NA, NA) )
#' is_duplicated( c(NA, NA), na.rm=TRUE )
is_duplicated <- function(vect, na.rm=FALSE, ...) {

	isdup = vect[ base::duplicated(vect, ...) ]

	if( na.rm )
		isdup = na.omit(isdup)

	vect %in% vect[isdup]
}