Find values in a dataframe and replace them by NAs. Also give the liste of the variables implied Beware of the factors. The variables stays as factors and the level is still in memory.
purge_values(base, value)the dataframe to clean
the value or vector of value to find and remove. if "space" it removes the blank thousands separator.
a list with "base" as the cleaned dataset and "list_var" as the list of indexes of variables that have been changed.