The 
triple exponential average (TRIX) indicator is an oscillator used to identify oversold and overbought markets, and it can also be used as a momentum indicator. Like many oscillators, TRIX oscillates around a zero line. When it is used as an oscillator, a positive value indicates an overbought market while a negative value indicates an oversold market. When TRIX is used as a momentum indicator, a positive value suggests momentum is increasing while a negative value suggests momentum is decreasing. Many analysts believe that when the TRIX crosses above the zero line it gives a buy signal, and when it closes below the zero line, it gives a sell signal. Also, divergences between price and TRIX can indicate significant turning points in the market.

TRIX calculates a triple 
exponential moving average of the log of the price input over the period of time specified by the length input for the current bar. The current bar's value is subtracted by the previous bar's value. This prevents cycles that are shorter than the period defined by length input from being considered by the indicator.

Advantages of TRIX
Two main advantages of TRIX over other trend-following indicators are its excellent filtration of market noise and its tendency to be a leading than lagging indicator. It filters out market noise using the triple exponential average calculation, thus eliminating minor short-term cycles that indicate a change in market direction. It has the ability to lead a market because it measures the difference between each bar's "smoothed" version of the price information. When interpreted as a leading indicator, TRIX is best used in conjunction with another market-timing indicator - this minimizes false indications.