Translated from Russian by MetaQuotes Software Corp.
Original code: https://www.mql5.com/ru/code/7350
The Parabolic SAR was also developed by Welles Wilder for use in trending markets. The author of this indicator recommended to identify the trend first, and only after that to use the PSAR for trading with the trend.RSTL
Reference Slow Trend Line (RSTL) is a response of the SATL digital filter to the series of input prices with a delay equal to the Nyquist interval of 1/2F.