R/copy.attributes.R

In magclass: Data Class and Tools for Handling Spatial-Temporal Data

#' Copy Attributes
#'
#' This function copies attributes from one object and assigns them to another.
#'
#'
#' @aliases copy.attributes copy.attributes<-
#' @param from object from which the attributes should be taken
#' @param value Same as "from" (object from which the attributes should be
#' taken)
#' @param to object to which the attributes should be written
#' @param delete attributes which should not be copied. By default this are
#' class specific attributes which might cause problems if copied to another
#' object. But you can add or remove attributes from the vector.
#' @param delete2 Identical to delete and just added for convenience for the
#' case that you want to delete additional attributes but do not want to repeat
#' the vector given in delete. In the function both vectors, delete and
#' delete2, are just merged to one deletion vector.
#' @author Jan Philipp Dietrich
#' @examples
#'
#' from <- array(12)
#' attr(from, "blablub") <- "I am an attribute!"
#' attr(from, "blablub2") <- "I am another attribute!"
#'
#' print(attributes(from))
#'
#' to <- as.magpie(0)
#' print(attributes(to))
#'
#' copy.attributes(to) <- from
#' print(attributes(to))
#'
#' @family ObjectCreation
#' @export
copy.attributes <- function(from, # nolint: object_name_linter.
                            to, delete = c("names", "row.names", "class", "dim", "dimnames"), delete2 = NULL) {
  a <- attributes(from)
  a[c(delete, delete2)] <- NULL
  attributes(to) <- c(attributes(to), a)
  return(to)
}

#' @describeIn copy.attributes assign attributes from object "value"
#' @export
`copy.attributes<-` <- function(to, # nolint: object_name_linter.
                                delete = c("names", "row.names", "class", "dim", "dimnames"), delete2 = NULL, value) {
  return(copy.attributes(from = value, to = to, delete = delete, delete2 = delete2))
}