R/subset.varlist.r

In flynnzac/rata: An Imperative Library for Data Manipulation

#' generate a varlist that is a subset of another
#'
#' @param x a varlist
#' @param vars a set of variable names
#' @param ... currently ignored
#' @return returns the subset of variable names with an attibute "type" giving the types.  The vector is of class "varlist"
#' @export
subset.varlist <- function(x, vars, ...)
{
  vars <- gvcharexpr(enquo(vars))
  names <- x[x %in% vars]
  attr(names, "type") <- attr(x,"type")[x %in% vars]
  class(names) <- "varlist"
  return (names)
}