R/show_var.R

In mixgb: Multiple Imputation Through 'XGBoost'

#' Show multiply imputed values for a single variable
#' @description Show m sets of imputed values for a specified variable.
#' @param imputation.list A list of \code{m} imputed datasets returned by the \code{mixgb} imputer.
#' @param var.name The name of a variable of interest.
#' @param original.data The original data with missing data.
#' @param true.values A vector of the true values (if known) of the missing values. In general, this is unknown.
#' @return A data.table with \code{m} columns, each column represents the imputed values of all missing entries in the specified variable. If \code{true.values} is provided, the last column will be the true values of the missing values.
#' @export
#' @examples
#' #obtain m multiply datasets
#' library(mixgb)
#' mixgb.data <- mixgb(data = nhanes3, m = 3)
#'
#' imputed.BMPHEAD <- show_var(imputation.list = mixgb.data, var.name = "BMPHEAD",
#'   original.data = nhanes3)
show_var <- function(imputation.list, var.name, original.data, true.values = NULL) {
  na.idx <- which(is.na(original.data[[var.name]]))
  result.l <- lapply(imputation.list, function(dt) dt[[var.name]][na.idx])
  names(result.l) <- paste("m", 1:length(result.l), sep = "")
  result.df <- do.call(cbind.data.frame, result.l)
  result.dt <- as.data.table(result.df)
  if (!is.null(true.values)) {
    result.dt$true <- true.values
  }
  result.dt
}