public static int getTwoTermFreq(Term fromTerm, Term toTerm) {
        Nature from = fromTerm.natrue();
        Nature to = toTerm.natrue();
        if (from.index < 0 || to.index < 0) {
            return 0;
        }
        return NATURETABLE[from.index][to.index];
    }
public static int getTwoTermFreq ( Term fromTerm , Term toTerm ) { Nature from = fromTerm . natrue ( ) ; Nature to = toTerm . natrue ( ) ; if ( from . index < 0 || to . index < 0 ) { return 0 ; } return NATURETABLE [ from . index ] [ to . index ] ; }
获得两个term之间的频率

@param fromTerm
@param toTerm
@return