Usage: When the market trend is obvious, the index effect is ideal. PDI (rising direction line) MDI (falling direction line) ADX (trend average line) 1. The PDI line breaks through the MDI line from bottom to top, indicating that there are new bulls entering the market, which is a buying signal; 2.PDI line falls below MDI line from top to bottom, indicating that there are new short positions entering the market, which is a selling signal; 3. when 3. ADX value continues to be higher than the previous day, and the market will maintain the original trend; 4. Number four. ADX value drops below 20, and the market atmosphere is consolidation when moving horizontally; 5. when 5. ADX value changes from an upward trend to a downward trend, which indicates that the market is about to reverse. Parameters: n Statistics days; The number of days between m is generally 14, and the 6 ADXR line is the average of the ADX value of the day and the ADX value before m.