It represents a standard MovingAverage indicator with the function of smoothing by the second-order Butterworth filter added. It is balanced so that if the same smoothing periods are selected the weight of the current count will correspond the weight in the Exponential Moving Average. In order to choose the Butterworth smoothing specify MA_Method=4.
Translated from Russian by MetaQuotes Software Corp.
Original code: https://www.mql5.com/ru/code/8538
Indicator of Bollinger bands.Madeleine_v2.0
Another version of the Madeleine indicator.