question: public static Map ordinalMap ( Iterator tuples , String field , Comparator cmp ) { Object [ ] o = ordinalArray ( tuples , field , cmp ) ; HashMap map = new HashMap ( ) ; for ( int i = 0 ; i < o . length ; ++ i ) map . put ( o [ i ] , new Integer ( i ) ) ; return map ; }
target:  Get map mapping from column values (as Object instances) to their ordinal index in a sorted array.