R/overwrite.R

In michaja/quitte: Bits and pieces of code to use with quitte-style data frames

#' Replace rows in a data frame with new values
#'
#' \code{overwrite()} \code{rbind()}s the data frames \code{lhs} and \code{rhs},
#' removing any duplicate lines, which are determined without regard to the
#' columns in \code{except}.
#'
#' @param lhs data frame with values that will replace others
#' @param rhs data frame with values that will be replaced
#' @param except names of columns that will not be considered in determining
#'               which columns to replace; defaults to "value"
#' @return data frame in which rows from rhs have been replaced with rows from
#'         lhs
#' @author Michaja Pehl
#' @examples
#' require(dplyr)
#' data <- data.frame(expand.grid(UPPER = LETTERS[1:2],
#'                                lower = letters[24:26]),
#'                    value = 1:6)
#' data
#' data %>%
#'   filter(lower == "y") %>%
#'   mutate(value = value * 10) %>%
#'   overwrite(data)
#'
#' @export
#' @importFrom dplyr '%>%' distinct_
#'

overwrite <- function(lhs, rhs, except = "value") {
    return(
        rbind(lhs, rhs) %>%
            distinct_(.dots = setdiff(colnames(rhs), except))
    )
}