R/clean_names.R

In shug0131/cctu: In-house Functions for Report Writing at Cambridge Clinical Trials Unit

#' Tidies up names of a data frame within certain rules
#'
#' @param df a data frame
#' @param convert a logical to indicate if you want to modify \code{df} in the parent environment,
#' or if not simply return a character vector of the revised variable names.
#' @param verbose logical to print information on changes to the global environment or external files. Defaults to options()$verbose.
#'
#' @return \code{df} is modified to have variable names that are
#' \itemize{
#'   \item lower case
#'   \item dots, slashes,+ replaced with _
#'   \item no leading or trailing whitespace
#' }
#' so a variable called "Nasty/Var+Name " gets turned into "nasty_var_name" .
#'
#' \code{clean_names} returns either a vector of cleaned names is return directly,
#' or the input object is modified in the parent envirnoment (the default) and an invisible copy of the modified input returned
#'
#'
#' @export
#' @importFrom  magrittr %>%


clean_names <- function(df, convert = TRUE, verbose=options()$verbose){
  arg_name_df <- deparse(substitute(df))
  df_names    <- clean_string(names(df))

  if(convert){
    names(df) <- df_names
    assign(arg_name_df, df, envir = parent.frame())
    if(verbose){cat(arg_name_df, "given clean names")}
    invisible(df)
  } else{
    df_names
  }
}

#'
#' @rdname clean_names
#' @export
#'
#' @param x a character string to be cleaned.
#' @returns \code{clean_string} returns an individual vector with the contents cleaned.
#'
clean_string <- function(x){
  x %>%
    tolower(.)          %>%
    gsub("\\s+","_",.)  %>%
    gsub("-","_",.)     %>%
    gsub("/","_",.)     %>%
    gsub("\\.", "_", .) %>%
    gsub("_+", "_", .)  %>%
    gsub("^_", "", .)   %>%
    gsub("_$", "", .)   %>%
    trimws
}