-single characters corresponding to input values.
-A specified sequence of unicode characters will be used for
-Of a specified sequence of unicode characters,
-the first one will be used for non-values,
-the last one for the maximum,
-the second (if any) for the minimum,
-and any remaining will be distributed over the range of values.
+single characters (configured by C<--indicators>)
+corresponding to input values.
+
+=item --indicators[=<characters>]
+
+Prefix a unicode character corresponding to each value.
+The first specified character will be used for non-values,
+the remaining sequence will be distributed over the range of values.