The function finds the critical value, if used to separate the units, that maximizes the sum of proportions of true classification for both categories. Lines beginning with a character (column names) are excluded. Each record must be in a separate row, column separator can be either space, tab or semicolon, decimal separator can be either point or comma. The option Codes and values enables to discriminate categories with mixed values of up to 255 variables. In this case the grouping codes must be integers from 0 to 255.