Create a 'Total' column of character type comprising exactly of
one unique value. This is a convenience function for returning a no-HR
attribute view when
NULL is supplied to the
hrvar argument in
totals_col(data, total_value = "Total")
Character value defining the name and the value of the
"Total" column. Defaults to
"Total". An error is returned if an
existing variable has the same name as the supplied value.
data frame containing an additional 'Total' column on top of the input data frame.